otoupalik

Ok - totally lost. As for point one - stiffer is not always better. Well, this just comes from testing. Some chassis can take a stiffer set-up some cannot. The C32 and the e46 M3 for example are NOT faster with stiffer set-ups. This is often misleading as they "feel" more connected. However, when you run the car on the track or a twisty bit, the clock does not lie. We often have to teach people that what feels fast is not and what feels slow is often fast!

PTG v. Porsche motorsports is a perfect example. Back when BMW was in ALMS, they ran the cars very soft compared to the otehr cars (ie: Porsche's). Watching them for many races and talking to friends that drove for both the BMW factory and Porsche teams, we woudl all discuss this. They said the Porsche's were wicked fast on VERY smoth tracks with little undulation and high grip (makes sense - the stiffer the car, the less travel the suspension and less the geometry of the car is allowed to work - but if that geometry is not needed - SUPPED SMOOTH ROAD - it is no problem). However, the BMW was faster at 90% of the tracks as most were not super smooth. We see this played out on many levels.

In our own testing for the World Challenge cars and the Club Racers, we have also continually softened our race cars from the "german standard" to softer settings. On the tracks we have in the west (very bumpy, except Laguna Seca) we have picked up tons of speed!

The correlation here is that real roads are NEVER as smooth as the smoothest race track. Super stiff suspensions will not allow the chassis and the geometry to work. This limits travel and causes the car to skid or slide rather then carve.

Does that help explain it at all? This is all borne out of 100's of hours of suspension study, testing and reseach.

Point 2 - the 500lb GC set-up is NOT soft. In fact, it is their full race set-up. We have installed these along with their street/track set-up (which is 300/300) and the 300/300 is faster on the street. Same principle as above, the car carves rather then skids. The car may feel more connected to the road, but when pushed to 10/10ths, the car will break away before the 300/300 set-up under all but the most ideal roads.

If you need a place to do this, let me know. I know of all the places, I really only trust two. One is in the valley and one in HB.

However, I bet you will find that the values are all very close. We have never found the value in spending the time and money to do this to street suspensions. We have dyno's on Motons, JRZ's, and Penske's - but never on a street suspension. The values are somewhat meaningless. What you want is to find a set-up that give you the feel that you like, and that info cannot be found on a dyno, but only in driving! We trust in H&R as we know that every kit is tested on the autobahn and on the 'Ring. I have seen the factory and know what they do to make things work!

Yea, not that much. We do have the system going now to get the evo/RS version done. It will be about 6-8 weeks though. And they will be in limited production.

The Carlsson RS suspension is also available as you know. I have not ridden in one, so Justin, let me know when it is in so we can see it first hand (return the favor for when you took out our C32).

Not at all, just replying to why we don't use that part. You said it was avaialble, and I am replying why we do not use it. Sorry if you took it another way. Further, how is it stirring up trouble letting people know that A. the aprt is available at 25% of RENNtech's price and B. We have had major failures with this brand in other cars?

Sounds like you are stirring up trouble! As you have posted all of 10 times before this thread, I am not sure why you have such an agenda or where you get your info - as it is clear you are NOT a baord regular.

No one has EVER been banned for as you say "anything about H&R or its “vendor” and boom you get banned or your posts get removed." Of course, it sounds like you have an agenda, so don't let me get in the way!

What in the world are you talking about in the last paragraph? Totally lost. Maybe post NON-ANNON and we can see who you are!

Now, STOP thread hi-jacking, let this thread take the course that carl wanted!

Thanks

Brad

carl

Thanks Brad. Some people just speak without thinking.

Zeppelin

For those who seldom track their car a mild lowering and the MB camber bolts is all they need. The tires will wear just as fast on the inside as they will on the outside edge. Granted adjustable camber will be best with a range from -0.5 to -4.0 giving us street and track adjustability.

For those who are driving on the rim or are wearing off the lettering on the side of the tire, do you know that when the car is understeering that additional steering input will not make it understeer less. It will only wear off the edge of the tire as you are describing.

JustinTRW

LOL. Yes, we know this. Throttle steering is a common technique. BTW, my rear tires are wearing on the edges just a bit as well, but not much.

speedybenz

What sort of negative camber numbers seems to work out best for using DOT race tirers at the track for both the M3 and C32?

Do you run more camber in the fronts than in the rear?

Thanks,

Jeff

otoupalik

Each car and tire is a bit different, however here is what we have found to work:

M3:

Kumho/Michelin - 2.5deg
Hoosier/Slick - 3+deg

The rear camber we typically run .5 to .75 degrees less.

These numbers are also dependent on the ride height (due to scale work).

These numbers are just a base point. For a race car, what we do is set it up like this and then we will go and use pyrometers to make fine tuned adjustments and usually end up with an asymmetrical set-up.

I would start the C32 at the same numbers and adjust to suit the pyro numbers.

Thanks

Brad

PS - Justin, I will get back to you on your PM today for sure!

Larry Sonsini

And do you take just inside/outside readings with the pyro, or is there more to it than that? Also, do you move towards even temps across all tires? I would assume that the end point would be asymmetrical because all of the turns on a track cumulatively, are not symmetrical. Also, could you explain the set up process as it relates to tire pressures?

TIA, as I'm not the most technically proficient guy out here.

otoupalik

PYRO:

inside - middle - outside

You look for the spread across the tires. What you want to see is the inside number the highest, the middle number VERY close to the inside and the outside number less. Ideally you woudl want them all the same, but that is almost impossible!

Larry, can you clarify "could you explain the set up process as it relates to tire pressures?" - I am not sure I understand what you mean.

Thanks

Brad

Larry Sonsini

I'll chat with you more later today, but what I mean is, how do you go about finding the ideal tire pressure when making track runs? You've talked about tire temps as it relates to camber adjustments, but what about other "adjustables?" Do you go through each of the variables systematically?

For tire pressures, do you just go by the roll line or are there other things to look for?

CynCarvin32

Brad, let me address your rebuttal to my comments with the following responses and questions, which outline specifically my disagreements with your statements and logic.

“Ok - totally lost. As for point one - stiffer is not always better.”

As this is sometimes true, we need to address this theory specifically for the C32, as each car is a little bit (or a lot) different. You make mention to the C32 and E46 M3 specifically and state that: “The C32 and the E46 M3 for example are NOT faster with stiffer set-ups.” I would unequivocally state that you are wrong. And to prove it, one only needs to look at your web site and the statements you have made within this thread. If this is true for the M3, then why do you sell shock and spring upgrades that have proven and tested higher spring rates and shock valving than stock? Are you saying that the H&R standard non-adjustable kit for the car is faster than the PSS-9, Koni dual adjustable, Korman, TCKline, or Turner’s showroom stock setup? Or the Penske set up on the same car, same track, and same conditions? The H&R is the softest of the bunch and the slowest in any setting. The H&R standard kit was meant for the average street driver who wants an adjustable ride height and a better matched set of shocks for a particular and softer spring rate. This is not bad, just meant for a different type of driver, and certainly not the fastest in the corners, street, canyon or track. And if your assumptions are correct (and I don’t believe they are) that the Ground Control street kit which uses dual adjustable Koni’s with your stated spring rates of 300/300 handle better than their track set up with much higher rates and valving, than do you agree that the Ground Control street suspension handles better than the standard H&R street kit because it is valved and sprung higher, or do you want to restate that the H&R standard coil over for the E46 M3 is the fastest suspension spring and shock upgrade you can by for a street driven car? There are a lot of BMW forum members as well as your own customers that would like to specifically hear your official statement on this subject mater.

In the case of the C32, then are you saying that the current H&R coil over set up is better only due to its ride height adjustability, since you think that the spring rates are very similar to stock ratings and they are all basically the same in nature? Or due you think that the H&R in addition to this height adjustability, is better due to its valving design or quality of materials and workmanship? In addition, if the current H&R coil over set up is so good and “feels” just right, or is the “best” on the C32, then why are you having H&R custom valve a set of coil overs and springs for the C32 to your “stiffer” parameters? Haven’t you been saying all along that stiffer is not always better? The following are your words:

“We do have the system going now to get the Evo/RS version done. It will be about 6-8 weeks though. And they will be in limited production . . . We are going to have them make a stiffer kit to our specs though, and those rates, we will know and publish.”

I am glad you have chosen to publish you kits specifications for spring rate and shock valving. This is useful information for people who think that product specs are helpful in tuning a car regardless of the car’s driven intent. I am sure you know what the specs are for the standard H&R kit and are basing your Evo/RS kit rates on a % increase off of the standard offering as a base line for your Beta testing. If you don’t mind me asking, what were all the different spring rates and shock valving you tested, and what were the incremental handling results, positive and negative, of these different set ups? Or since street suspension spring and shock valving is not important, since it is the “feel” that matters most as you sit behind the wheel, are you then allowing H&R to guess for you what the customer wants in terms of a stiffer feel without any testing by your own test drivers through 100’s of hours of specific model testing in real driving situations?

You stated: “However, I bet you will find that the values are all very close. We have never found the value in spending the time and money to do this to street suspensions. We have dyno's on Motons, JRZ's, and Penske's - but never on a street suspension. The values are somewhat meaningless.”

Why do you say this? Then if this is true, then why spend the time and money to do this on the other suspensions? Why compare the Motons, JRZ’s and Penske’s on a shock dyno if the numbers are meaningless and only seat of the pants “feel” is what is important even in a racecar? What I don’t understand is why would you design a new H&R coil over suspension system around a different set of spring and shock values if the current system feels the best for the C32? The only logical conclusion is that a stiffer offering over the current standard offering by H&R will make the car handle better. If not, why then would you go to the great expense and effort to produce a kit that would be worse? By the way, it usually cost around $15.00 to test each shock and spring.

I am sorry, but the rate is not just a number. It is a very important parameter to know. In suspension tuning, you always start with a spring rate in mind and then tune the shock around this value. The shock’s function is to control the spring, not the other way around. This is why knowing the spring rate is so important, whether you are running a 150lb spring or a 1,050lb spring.

“PTG v. Porsche motorsports is a perfect example. Back when BMW was in ALMS, they ran the cars very soft compared to the other cars “

A BMW is not a Porsche, and an Apple is not an Orange. It is not fair to confuse the subject matter here by comparing two different cars and manufacturers. The proper comparison would be to individually look at suspension theory and practical application within each car, and only compare them to themselves. It is quite possible that Team PTG ran very high spring rates and shock valving compared to other BMW teams at the time or from their own testing results. They found the combination that worked and was the fastest at each track. In addition, teams frequently switch spring rates, shock valving, sway bar diameters and settings, alignment specifications, and tire pressures for each track they run as well as for weather condition changes. I can assure you that having some knowledge with PTG’s M3 campaign during their GT-3 winning years, their suspensions were significantly stiffer than any street legal M3. And if they had softened their suspensions from what was on their car, their times would have fallen. As for the Porsche, it is quite possible that Porsches in general run stiffer spring and shock values due to the nature of the car compared to the BMW. The polar movement of a Porsche is also quite different that in the BMW. There are many reasons why you can’t compare them fairly. It is also quite likely that if the Porsche teams softened their suspensions from what was on their car, they also would have been slower. You can talk to Kurt Wagner or Bill Auberlen about these specific suspension tuning options, experiences and recommendations as you are friendly with them and they have taught at your driving events.

But these are racecar specifications and the comparisons you are making here are not real world examples of the cars we drive everyday and have fun with. If Tom Milner was to make a street going version of an M3 today, you can bet that the spring and shock valving would be stiffer than stock or stiffer than the offering by H&R or Bilstein. They may be closer to what Will Turner, TC Kline, Korman, GC, etc. run in their street prepared or modified M3’s or 325/328/330’s they campaign in SCCA or the Speedvision series. Furthermore, BMW’s own “M” division produced the new CSL with stiffer springs and shocks than the standard M3. Were they wrong in doing this? In fact, your Evosport E36 M3 Ltw runs significantly more spring and shock than the H&R and Bilsteins offered for the car and your car is much faster at Willow Springs than a H&R standard coil over E36 M3.

CynCarvin32

“Does that help explain it at all? This is all borne out of 100's of hours of suspension study, testing and research.”

No, and it makes no sense to most who are familiar with suspension set up. How many hours were devoted to your new Evo/RS suspension for the C32?

“In our own testing for the World Challenge cars and the Club Racers, we have also continually softened our race cars from the "German standard" to softer settings.”

I am sure that you would agree that these so called “softer” setting are in no way considered soft in the context of this conversation. Your soft settings are much stiffer than any streetcar would run or any settings available from H&R’s street application listings. You have to also remember that the generic European preference is to run stiffer springs and softer sway bars vs. the US, which like to tune cars with softer springs and stiffer sway bars. The results are often the same, just a different way of arriving at the same place with a different “feel”, not necessarily a faster or slower car. Were the German standard cars you are referring to also running stiffer sway bars? Every driver likes his car to drive a certain way according to their individual preferences. I am sure that Kurt and Bill would have their differences in which suspension set up would be “their best” setup in both the BMW and the Porsche, and Bill has a lot of Porsche racing experience.

“We have installed these {race set up} along with their street/track set-up (which is 300/300) and the 300/300 is faster on the street.”

I don’t believe the GC is running 300lb front and 300lb rear springs on their street/track set up for the M3. This is way too soft especially for the rear of the car. I will find out from Jay what the numbers are. Guaranteed, a higher rate front and rear spring with a shock valving matched to the higher spring rate number (the dual adjustable Koni’s that they use are ideal for matching various spring rate used for tuning the car) will perform better than the standard non-adjustable H&R coil over system for the car. In fact, I could arrange for a local BMW team driver, Boris Said, and motorsports director for No Fear, to test an otherwise stock E46 M3 with both the Evosport H&R coil over system and the Ground Control coil over system on the same E46 or even an E36 M3 on the same day at the same track under the same conditions and will bet that the H&R looses. In fact looser covers the entire expense associated with putting on this test and we get the car from the BMW press fleet upon Satch’s approval and a possible article on coil over performance in the Roundel.

“H&R is VERY tight on this info. I have a ballpark, but will not put it in print. Guess less then 200lbs . . . As I said, it was a guess, but you should realize that the suspension is made up of more then just the spring rates, it is the combination of valving and rate. Also, the rate is just a number. You have the kit - does it feel too soft? . . . The e46 M3 kits are around the same rates and on that car also, they work great!”

Are you saying that improvements in handling and speed cannot be made to the BMW H&R standard coil over kit as well, and there is no benefit in stiffening up the spring rates and shock valving because the H&R also “feels” the best on this car?

I would like to test all the suspensions available for the C32 at my expense. I would appreciate you providing the names and phone numbers for your two referenced locations that have the equipment to do this kind of testing. Can I borrow a set of your H&R standard coil overs to take along for the test?

“We have looked at the kit and find it less then the quality that we like we have had problems with this manufacturer before . . . the part is available at 25% of RENNtech's price and B. We have had major failures with this brand in other cars”

Does this mean that you have not tested this kit on the C32, but you are passing judgment just the same without giving them a try? Not very scientific? Even if they were to fail, according to your pricing on the same part, I, as well as other, would be more than happy to by four pairs of bushings for the price of one set and replace them three times after they fail! Please locate this manufacturer and let me know how I can place an order for the only significant camber adjustment product available for the C32 as of now. Part of the failure with these types of bushing may be caused by inappropriate pressure being exerted upon the bushing during the installation process. If you don’t freeze the bushing over night, and use a blowtorch for a few seconds to heat up and expand the hole where the bushing fits into, problems are likely to occur when pressing the bushing into place. What about the Kmac camber products for BMW’s and their high failure rate? And this product is still one of the most widely sold products for this type of adjustment on the BMW. Their rear camber bushing are notorious for failing as well as the camber plates cracking. Is BMP and Bavarian Autosport less reputable for selling an item that may have a chance of failing? Or is it the risk we take in modifying our cars?

By the way, what is your opinion of RENNtech’s rear sub frame kit?

What about developing a new Evosport camber plate kit for the W203? Not easy with the current bell housing design. Almost impossible to fit a strut tower brace as well. What will your new front arms do? Will they include offset bushings? Shorten the length of the arm? Change the mounting point geometry?

Who shall make your parts for the front thrust arm kit? You say that RENNtech simply sells other peoples parts at 3-4 times the cost. Is this not how car tuning works? You design somethng to your specs then you outsource to an external party for actual design, fabrication, and production. Your sway bars were made produced in this fashion so I do not see you logic here. What is your take?

The only way to get accurate times relating to a change in suspension setups of a particular car is to run them on the same day or in the same conditions with the same driver. Do you have Kurt’s times in all the cars? What was the difference between his times and yours in the same cars on the same days?

I hope that I have cleared up any misunderstanding that you may have thought we had. I am only interested in facts based on scientific principles and professional observations that are repeatable, and that is what I am trying to get at with this thread, which I have not hi-jacked, but boarded fairly with a ticket in hand and a destination to truth.

I will assume that your professional conduct will not cause this post to be removed from this thread. I have tried to be very polite and matter of fact with my responses stated above and mean no disrespect to you or Evosport. I am only challenging your points of view and statements contained within this thread.

schwarzwagen

In my experience with eccentric bushing designs that have been utilized to adjust camber, they are the most efficient and easily adjustable means of achieving personal specifications.

This opinion gains credence when you realize that ALL MBs used eccentric bushings until the recently. Why eccentric bushings are used no longer is a matter of debate. An overall cheapening of the product line due to fierce compentition and the blood sucking Chrysler unit is one.

Never-the-less, my logic tells me that designing eccentric bushings for the C32 would be the way to go considering that's the conclusion MB came to decades ago. Is evosport going to design eccentric bushings to go with the new arms? Or is the customer going to have to buy several different legth arms that will require 'viel geld' for installation, removal, and reinstallation everytime they want to change camber?

And the fact that Renntech decided on eccentric bushings to adjust camber makes sense to me because the owner/founder of Renntech, Mr. Feyhl, is from AMG.

Just some Q's from an MB owner WITH eccentric bushings...

otoupalik

PART 1:

Wow, DID YOU EVER READ A LOT INTO WHAT I SAID AND MAKE LIKE A MILLION ASSUMPTIONS! Of course the stock H&R street set-up will not be the fastest of them all (well, it actually could be on certain roads or tracks). The point is that you cannot just keep going stiffer and stiffer. You will reach a point where the chassis cannot work correctly (where the geometry is not allowed to work) and you will start to loose speed. Talk to Jay Morris - he and I see eye to eye on this. On some roads or tracks, a car might be fastest with a 300lb spring, on another it may be a 600lb spring, the point is that softer is sometimes better and you need to find the right medium with the car is allowed to work rather then just sliding the car around as the suspension is too stiff!

Now, you don't have to agree with me, but I have set-up winning race cars for 3 years. I have studied many books and learned from experts in Germany and the US. I would love to know what experience you actually have that is hands on? Or are you just recanting things you have heard without actually ever trying and experimenting yourself. I have set up cars with Penske's, JRZ's Moton's, Koni's, Advance Design's, Bilstein's and H&R's. Each car takes a different set-up and sometimes we will vary spring rates by as much as 200lbs between tracks!

This is NOT what I have said at all, but keep making assumptions! The fact is the nature of the spring (the rate of progression is VERY different then the stock springs. Also the rate is stiffer at the higher points of compression, I am just not going ot give out the exact rates as it took H&R 13 months of testing to get it right and I am not going ot give that info away for free!

Yes, it is better in the valving, specifically in the progression. Also, of course the quality is better, they are handmade to a specific setting rather then production run parts with cost as the primary variable.

Yes, stiffer WILL be better (but again, to a point, we are not going to use 600lb springs) for the track and VERY aggressive drivers. I think you are getting so caught up in the word "STIFFER" without realizing that you can use a 50lb stiffer spring or a 1000lb stiffer spring. But regardless, each chassis has a limit where the geometry and other suspension components stop working properly, and at that point, you have gone too stiff.

I am not at liberty to give away valving. Also, I do not know what the evo/RS kit will be as we will have to test multiple valving/spring rate combo's till we find the right set-up that is a good compromise on multiple road surfaces. We allow H&R to design the street kits as NO ONE DOES IT BETTER. However, the specialty kit will be made to our specs with us doing the R&D and testing.

You do NOT use the race shocks on the street. In professional racing, a 1/10th of a second is critical. It is important to know the way the shock works - and this is not just rate, there are MANY important variables to tuning a shock/spring combo.

We will design a new set-up as we want a track/canyon set-up that is more aggressive then the kit that 95% of the street drivers will want. I am not sure why this is so hard to understand. There is not one suspension kit that is everything to everyone. Tuning a car is about compromise, you have to compromise multiple factors to achieve the right result for the given goal.

If you think this is important to know on a street car - you are lost! You will never be pushing your street car hard enough that this will be important. I am sorry, it is not possible. And if you are, then you are a total maniac and will kill someone one day as you lose control of the car.

otoupalik

PART 2:

YES - ON A RACE CAR! We are talking about street cars, man. It is clear to me know that you have heard/read some great information, but have no practical real world knowledge of this. You are taking things totally out of context and mixing the lines of street vs. race. BTW - tracking a car is not the same as racing it.

OF COURSE - But as you say, they switched rates - why? BECAUSE STIFFER WAS NOT ALWAYS BETTER! If it was, they would have used 1200lb springs and never changed them! That is the point!

Wrong. We are talking street cars and no one said going stiffer then stock was wrong, I said that stiffer is not always better. Which means that you can go too stiff, and many people do. Also, Will uses PSS9's on his car with standard springs. I use the evo/RS kit. TC uses Koni's with H&R's. I know their rates, do you? Our LTW uses stiffer the stock springs, but not as stiff as many of the "tuners" use - all becuase the car was slower with them - PERIOD. We use 550lb front and 675lb rear, you know why? Because anything stiffer is slower and anything softer is slower!

otoupalik

PART 3:

LOL - like who? Why don't you call people like Jay Morris or Will Turner, they will tell you the exact same thing I am! They are good friends of mine, we all have had deep discussion on this!

NO time has been put into the evo/RS C32 suspension, as we have not started it!

NO - I TOTALLY DISAGREE. They are considerably softer then what you might think and are way softer then what most people run. They ARE considered soft as far as race cars go. The reason we run them again, as we went stiffer, and is was not better!

Yea, but so what? That is not the point. You said, stiffer is always better - well, it is not! This was just one more example of that!

LOL - OK, well then I guess the dozen kits we have done this way were just my imagination!

OF COURSE THE STANDARD H&R WILL LOSE!! No one will doubt that. But run a CG system will 700lbs springs and one will 300lb springs or even the evosport/H&R suspension, and the 700lb sprung car will be MUCH slower! Again, you are so caught up in what you are saying, you are totally missing the point. You are not seeing the forest for the trees. No one ever said that a softer suspension will always be faster or that a stiffer one will never be faster. What I have said from the start is that there is a point where stiffer is not faster, that it is slower. Why is this so hard for you to understand?????

I am not even sure what you are saying anymore. I never said that the stock kit was the fastest, what I said is that you CAN go too stiff, or specifically, what was said was "stiffer is not always better."

E-mail me privately (brad@evosport.com) and I will give you the names and numbers. These are the only two places I would trust.

Yes and you are right. But you know what, I don't care! I would rather play it safe and not let any of my customers experience a problem when I have had a LOT of issues in the past on multiple different chassis with this manufacturer.

I have spoken with two shops that have installed the kit on the 209 and swear they will never do it again - I cannot repeat the words used to describe the kit.

Also, I know for a fact that you have had problems with your front suspension and that these parts may be in part to blame! So, yes, scientific or not, I will play it safe!

I will not give it out. I will not be part of helping to put a part on a car that I know may be a problem. I went to law school, I have seen the downside of this type of "advice" and will, again, play it safe!

Don't know anything about it, I think Ben does, so you should ask him. I think I remember hearing it was made by the same maker as the front camber kit.

In fact, we are working with a company that does this with great success on the imports. It will not be cheap to develop, but we moving forward in Q2, 04 as I feel it is needed.

Yes and no. RENNtech is not having them designed to their specs. They are using off the shelf parts and re-badging them. To me this is offensive. Most of their performance parts are MKB with 2x-3x the price even. (BTW, MKB confirmed this to me in person in Germany).

When we make something with our name, it is exclusive to us and we have some say in the design. This is the only honest way to do it IMHO. The sways are a perfect example. No, we have no fabrication equipment in house to make them, but they were made to our specs and we paid for ALL the R&D.

Not true. You can average multiple days and account for conditions. Again, experience is key as you know what you know based on what you have done in the past.

Yes, this is FAR less aggressive. I have to tell you, I really felt attacked and that you were WAY TOO AGGRESSIVE BEFORE! Thanks for toning it down!

If I was going to delete it, I would not have spent all this time to reply. Thanks for being less aggressive and I will be happy to continue the discussion in this tone!

Thanks

Brad

CynCarvin32

Just some more thoughts:

Thanks Brad for you response. I am not your enemy. I am just trying to see through the smoke. The reason for my post is to clarify that there is not just one "best" suspension for the C32. Unfortunately, you company continues to posts statements like (I am paraphrasing here) "the H&R coilover is the Best suspension for the C32, period". We know that this is a subjective point of view and should be clarified.

For most drivers looking to improve the suspension characteristics of the C32 for typical street driving, the H&R coilover kit for the C32 provides a more aggressive adjustable lower ride height which lowers the car's center of gravity for better handling, while still offering an acceptable ride quality when driving down the boulevard. In fact, the H&R coilover kit is MORE comfortable than stock around town, while offering much better balance and a more performance tuned feel when you turn up the volume in the corners." I would not object in any way to a statement made like this from your organization or anyone for that matter. And I believe it to be true. The H&R coilover kit is a well manufactured kit that suits most drivers very well. It is priced right, has had great success across the model ranges that it is offered for, and was manufactured to be marketed as a replacement street oriented kit. Just don't say that it is the "best" kit available.

Bilstein, Carlsson, Kleeman, Brabus, RENNtech, KW, MKB, and others, all offer some type of suspension kit, adjustable or not, for the car. They are all good and none of them is the "best" for everyone, although everyone would probably be happy with any one of them, since they all offer a "better feel" and better performance than stock.

For those of us that want to push the car a little harder on the street, canyons, or track, there are better choices that offer better control under these conditions. That is why you are making your own "stiffer" kit. And depending on the low level frequency rebound valving of your Evo/RS kit, you may still be able to offer a comparable smooth ride around town, while increasing grip and limiting body movement in the fast corners. And I wish you good luck on this kit. But don't say that this Evo/RS kit is the "best" kit for fast driving in the canyons or track, unless you have tested them all under equal conditions and can support your claim with data that is repeatable and unbiased. Even then, driver preference comes into play and makes it impossible to have just one "best" kit on the market. Look at all the BMW tuners that we spoke of. They all approach suspension tuning a little differently and their spring rates and shock valving is not exactly the same. Their suspensions are tuned to what they feel is the best compromise for themselves or their customers.

I have to say, however, that your 6-8 week time frame for getting the EVO/RS to market seems optimistic. You your self said that H&R needed hundreds of qualified hours on the track and autobahn in order to settle upon the best-set spring rate and shock valving. I personally think that EVOSport will not have sufficient time to get those hundreds of hours of testing completed if the product is scheduled for release in just 6-8 weeks. I would be very interested to see what your in house testing (R&R includes). Where do you go and who is the suspension set for and what is its primary use? If you do not plan on doing such strict testing, how can the car be properly set? I am not passing judgment on your product being that it is not available and does not even exist (only in theory). Instead I am curious as to what you think it will be and to whom you plan for this kit to appeal? My judgment will of course have to wait for real, unbiased, testing. Would you say this is a fair assumption on my part? I am open minded so lets wait and see!

I agree that you can make a suspension too firm that will hinder its performance and have not stated otherwise. What I was trying to say is that any suspension made for the C32 could benefit from a stiffer set up than the current H&R values when you need to squeeze a little more out of the suspension in the turns. I will assume that the H&R kit uses a front spring rate of around 175lbs and a rear spring rate of around 335lbs. Shock valving should be somewhere around (using Bilstein's method of calculation) 200/45 front, 175/55 rear). If I were to design a kit for the car using the H&R non-adjustable system, I would probably go with spring rates of 300-375lbs front, and 400-450lbs rear, with valving somewhere around 235/90 front, 185/100 rear. Then again, if I were designing a system, I would use at least a rebound adjustable shock, if not a dual adjustable unit for more precise tuning. Do you have an idea of your starting point for your springs rates and shock valving?

I have a slight issue with your thoughts about RENNtechs products. I give you the credit you deserve for having designed your sway-bar kit (and anything else EvoSport has designed including your Pulleys and such) but it is slightly presumptuous of you to accuse RENNtech of being a re-seller of MKB parts. Unless you have seen this take place you do not know. I know people at both RENNtech and MKB and the number of joint projects between the companies are very few in number. This is nothing more than a way for them to lower production costs for limited runs of expensive motor components. I know for fact that RENNtech designed and tested its own springs for the C32 and that their ECU’s and motor modifications are NOT the same as MKB’s. Are they similar? Yes. But then again anyone who is tuning a Kompressor car will have an upgraded ECU and a different sized pulley kit (how different can these tuners be in theory?). I have driven many tuner cars including TechArt 996 Twin Turbos, Full Brabus Conversions CL500 6.1L (non kompressor), RENNtech SLK32, C32, SL55, Ground Control E46 M3 (with front and rear bembos, roll bar, seats, wheels, and such) and I honestly can say that all these cars are very high quality. The Brabus wheels may be heavy but they are very good looking. The 996 might need some sort or body bracing with its very stiff suspension but it is still a great car. And the RENNtech cars are no exception to this rule (I say even better). The SL and SLK I drove had these bushings you claim fail so frequently and they performed flawlessly (also the rear subframe kit…it was amazing).

As for my car, I respectfully ask you to not allude to why my car had trouble and spent a while in the shop. You do not know what the problems were and these problems all link back to the first day I had the car. A huge part of this is the fact that the factory rotors warp extremely fast and people failed to think that a 5k mile old rotor could be warped. I do not tell people what “could be wrong” with your car so please do not do that with me. Why are you trying to say my car failed? Warped rotors are not a serious issue.

I hope I have not offended you with this post, and have tried to be professional, although matter of fact, with all of my posts

CynCarvin32

What happened...thought we were having fun with this debate. Hope you are just busy with work. Curious what you have to say.

Have a good holiday

Sleestack

They're busy building my car... so leave them alone.

Harris

Eric, I guess a lot of the "smarter" members in here already know who has a slight edge on this debate. Well....just let it cool down for peace.

Essen Motor show starts Nov 28. Maybe thats why Brad is not responding because he is too busy promoting Evosport.

otoupalik

Yea, I have been very busy. I have made my points, I don't need to justify them over and over. We know what works - we do this for a living.

Thanks

Brad

Sleestack

I assume you are one of those "smarter" members. Given that you are in the business yourself, why don't you add something useful to this thread?

Harris

I intentionally didnt jump into the debate because I dont want to create more turmoil. Sometimes its wiser to be a spectator. Sorry, I chose not to comment and take any side on this thread.

Sleestack

Understood. Having read the thread, there seems to be alot more misunderstanding than disagreement. Both Brad and Cyn seem to agree that stiffer is not always better, however, disagree on optimal setups. Both agree that MKB OEMs for Renntech, but disagree on the extent to which that happens.

I happen to know that Brad and Evoport do a ton of R&D both on the street, on tracks and on dynos. I don't have my own data, however, I also know that Brad is not one to talk just for the sake of hearing himself. Evosport (and formerly Brad) race BMWs and have significant experience tuning cars for both street and race applications. I'm not particularly sure why Cyn has a problem with Brad's characterization of the H&R setup as the "best," given that Cyn himself admits that description can be a matter of opinion and, after all, we are talking about a company marketing a particular product.

As for the MKB/Renntech relationship, Cyn says he knows for a fact that the joint projects are limited, however, unless he actually has am ownership interest in Renntech or has actually seen all of Renntech's sourcing documentation, I'm not sure how this "fact" is any more substantiated than a claim of H&R being the "best." I have significant MKB parts on my car and have spoken to Panos of MKB. While things might of changed, as of last year, MKB claimed that they were still supplying alot of products to Renntech.... this may or may not be true, but only MKB and Renntech knows for sure.

As for Brabus wheels... they weigh a ton. Sure they look good, but, having wheels that weigh 33 lbs makes your car feel like it's glued to the starting line. I know this from swtiching from 18" Brabus Monoblock V multipiece rims to 19" BBS LMs... and this was on a CLK that dynoe'd at close to 400 hp at the rear wheel.

Healthy debate is always good... I just kind ogot lost on what was really being debated here.

CynCarvin32

Harris:

Thank you for the kind words. Any luck on the rotor hunt? Drop me an e-mail and let me know what you have been up to and if you have any new items. I am not trying to establish a winner or show who is smarter. I am just speaking my opinions. Why else have an on-line forum? Do we really want to sit here in a circle, hold hands, and sing Kumbaya? I don’t need someone to pat me on the back and say how wonderful I am. Personally think that a discussion works best when you have two willing sides to debate a topic.

Sleestack:

I just want to clarify my points here. Brad spoke very highly of the H&R system when he first started selling it but now that he was a different version on the way he seems to think that maybe stiffer is better. Is this marketing? I think so. Is it fact? I would venture to say it is not. In a car where a driver wants performance I think stiffer IS better (to a point – I do not support putting NASCAR springs is the front of a C32). I have driven the so called full race set-up for the E46 M3 from ground control, the one that brad said was to stiff for street use, and I can honestly say that car will pull always from anything I have ever seen in the canyons before (well if the other car was an E36 race car with R-Comp tires it would be a good run -- wait we did that already). The E46 with the 550/600 lb springs rides very well. The car is by no means harsh and the E46 chassis seems far happier with a stiff suspension that a W203 or W209 (hard to believe a BMW might be stiffer than a MB). I would drive that E46 any day of the week (and it has many new bushings and larger sway bars as well. My point for saying all this is that this car is firm but it is totally street drivable. We can pound over curbs at Buttonwillow and still cruise along the 101 at 65 mph in total comfort. Now that Brad has a new stiffer Coil-over kit coming to market, will he say this is better than the old? I am not sure. Lets see how they market the item before I pass judgment.

As for you thoughts on RENNtech and MKB, I agree and disagree. The flow of parts is so small that it is not worth debating. People try to make it seem like RENNtech simply buys parts from MKB and then sells them with their name. I know for fact that this is not true. If people want to think this is the case what can I do to change the situation – Nothing. I do know that RENNtech has sent MKB parts for building specific motors so the flow of parts is not just one way. Maybe they need the same piston for one motor both companies are making. Is it not cheaper to outsource to a production firm in Germany when you order 30 sets instead of just 15? I rather enjoy seeing two firms getting together to allocate the fixed costs of production over a larger production run. But I need to re-emphasize that this is not a common tactic for either company and only occurs once in a blue moon. Where did EvoSport get the Pistons, rods, cams shafts, and valves for your motor? I hope the pistons came from Kolbenschmid, the same firm that makes pistons for both RENNtech and MKB. Maybe your car will have mahle pistons but I personally think Kolbenschmidt is a superior company. It has been a while since I read what the specs of your car were going to be. Care to share? If I remember correctly I is going to be one quick beast.

Happy Thanksgiving to all those reading this post. Drive safely!

otoupalik

THAT IS TOTAL 100% BS and you know it!!!!!!!!!!

I have never changed my position. I have simply said for the 1% of people who want more, we are going to make it. I will stand behind our position that the H&R is the best street kit on the market, I have NEVER wavered from that - NOT ONCE. Prove it that I have. You have totally stepped over the line here. Mis-characterizing what I have said in a negative light is only something that you should be ashamed of. In the real world, people win debates with fact, not be twisting the other persons words. Sleestack and I are both attorney's (neither practicing for a living) - trust me we know how to twist words, we just choose not to!

Simply put, the proof is in the pudding. Do your OWN research and testing, then talk about it. Cyn, I have respect for your opinions (as they were obviously learned from someone else who knows something about suspension) but the way you apply them and communicate them is far from accurate. Harris, you on the other hand have never done any suspension testing, and in fact when you claimed the RS was the best thing since sliced bread, you had never even seen or touched one!

I love how people who have never done any pro racing or actual suspension testing/tuning can act like they know everything about it! So you have a few hours on track, that does not make you an expert. Let's talk credentials here so we can let everyone know what we are each basing our opinions on. In good faith, I will start. I have 85 days on track in 2002 alone, 55 in 2003 and 67 in 2001. I have over 10,000 hours of track time driving, not to count the time setting other cars up. I have finished top 3 in calss in every race I started in except for 3 where the car has borken. I have a SCCA PRO license and am in process for a FIA license. We have parts on and have helped nearly every BMW in World Challenge and the One C-class MBZ (a lot was in undoing the damage and faulty parts put on by the other MBZ tuner as it never could finish a race with their help). I have been retained to do ALL of the suspension testing/tuning on a Ferrari GT and Pagani Zonda LM program. I get paid to teach drivers who to be fast and to set up cars indepently of evosport. Do I know everythign about suspension set-up - NOPE - but what I know I have learned in theory AND tested, not just relied on someone else to tell me it worked. Harris, you show me one person on this board who has done more suspension testing then me or my company, and I will buy you a steak dinner. I know of three - let's see if you can find them!

As for the MKB connection - well, I sat in the MKB factory in Germany, and what I saw with my own eyes and was told sitting at the same table with MKB was proof enough for me. Have you been there? Are you a partner in RENNtech - of course not! Again, I love how you have no actual or constructive knowledge one way or the other and are simply repeating what RT tells you - of course they will say that! Think about what would happen if they admitted that they were MKB parts at a multiple of the price. Did they also tell you that the brakes are more then the standard Brembo kit (also BS, as their 14" kit that they originally sold was the standard SAME kit we sell with the ONLY difference being the RENNtech logo and they asked twice the price)?

Thanks, but again, I must say that if you want to have a constructive conversation, you might think about your approach to others!

'Nuff said!

Thanks

Brad