Grumpy - calm down! I do not have a personal vendeta against you and yes a 4 stroke does only intake once every other stroke. My 2-stroke racing history slipped in there unnoticed by me. However, the incremental principle that I used for heating and cooling of the combustion chamber is still the same.

Like I always told my crew chief, when all sixteen boats line up for the "Main" there are sixteen different opinions on what and how a boat works and should be set up, and the net result is all sixteen boats are still competitive. So, You and I are both intelligent guys and obviosly are both "Motor Heads". So, if it helps Grumpy your absolutely correct and I will not respond to anymore of your posts, however, I will still read them and try and learn something. I oppologize for upsetting you Grumpy. - Bob

 

That would explain the puzzled tone in their voices when I inquired.. Ah well.. It was worth a shot.

I guess I will try the methanol route and see if that helps, otherwise I'll get the ECU remapped to the stock pulley.

 

Perhaps if you took the time to read and comprehend the ************, then your posts wouldn't be laced with errors and misinformation.

Do I even need to comment on this? You don't even take the time to read your own posts.

What? When the RPMs reach the redline setting, the ECU starts cutting off the fuel, not adding it. The dip is probably an artifact of the sensor as the engine is shutting down.

You can add ten AFRs, but you still won't get any more pressure than the setting on the lowest regulator. He would have to remove/bypass the factory unit to increase the pressure. Perhaps the factory unit is adjustable. Have you looked?

No. No. No. At WOT, the car is in open loop mode. There is no ECU fuel adjustment until redline.

While this is an interesting suggestion, it's not very practical. To do it right, he would need to install eight of them - one for each cylinder. The sensor needs to be directly at the output of the head as the gas is entering the header. EGT tuning is used to equalize the exhaust temperatures between cylinders (ie, adjust each cylider's A/F ratio). It's not meant to adjust the overall A/R ratio - that's what the lamda sensor is for.

It's obvious to me that you don't have an in-depth knowledge on this subject - yet still, you profess to tell others what to do. How is this helping anyone? What is also obvious, based on your opening comment, is your maturity level. This will be my only response to your posts. I won't even bother to call out the errors in your second post. The forum members can decide for themselves how valid your input is.

 

Please let's not argue with eachother.. Let's just try and learn from eachother.

 

Grumpy sure does have away with words. - Bob

 

Grumpy I agree with your statement on the egt's to a certain extent. Having the sensors on each bank is the way to go on a race car because as you know individual egt's are affected by the manifold and cylinder heads ability to distribute air. So to get every last little bit of horsepower out of the engine you use individual cylinder correction from the engine management system. From my experience in drag racing I can tell you that on a good set-up the temperature differrence between each cylinder without correction is 50 to 150 degrees. That is why I think having even one egt probe close to the header is beneficial as long as you use it as a reference to changes you make to A/F. Three basic tools to tune on the street Lambda, boost gauge, egt probe. Grumpy what are your feelings about this?

 

OK, I'm back on my meds now. Sorry for being so abrupt and maybe a little rude.

Most of you guys are driving 6-figure machines. Someone on the board suggests that you do a mod to your car to achieve a certain outcome. You might not understand exactly what it's doing, but the guy sounds knowledgeable, so he must know what he's talking about. You do the mod - best case: it works - worse case: it does nothing and you're out the time and expense - worst case: it damages your car, and we all know what that usually costs. OK - who's held accountable?

As an example, let's look at Victor's car. He was told flat out that he's running too lean, so he needs to install an adjustable fuel pressure regulator to fix the problem. He agrees that it sounds like a good idea, so he does it. After a days work and several hundred dollars, he dynos the car, only to find out it doesn't work because the original regulator is still there limiting output. In fact, the car is now even leaner since the new regulator is causing an additional pressure drop by being in the line. Who's accountable?

For this and other reasons, I have a low threshold for less-than-knowledgeable people who are little more than posers trying to appear other than that. Most of them will defend their wrong position to the end and will not take the time to research the topic to gain more insite. We've already seen that in this thread.

In the future, if I remain here, I will try to be a little more polite when I call

And for those of you who are wondering about my background, I built and raced my first car in the late 60's - a '56 Chevy with a 283 that ran in the high 12's. I have worked in an automotive machine shop building and modifying engines and I used a chassis dyno for the first time in the early 70's. I also have an engineering degree from a Big Ten university and worked in the semiconductor industry for 20+ years making the CPUs that you're probably using. I drive a 540i and a whipplecharged GMC C3 with a 6 liter LS1.

 

Hi Guy's .Just wait until they go to Direct Injection and we get rid of the catalytic converter. Have 55 volt operating systems, for the injectors.!!!!

 

If you took the time to spell masturbation I would take your attempt at insult more seriously.

Don't comment on this. If you don't understand the difference bewteen tuning a NA car and an FI car, you are seriously lacking in knowledge. Run an FI car at lambda and it will last 100 hours or less. If you did not notice how lean his AFR is then obviously it is beyond your comprehension.

His fuel system is capable of flowing enough fuel b/c his fuel curve is not going lean towards redline - he is not limited by the combo of the injector+fuel pump+fuel pressure. The ecu map is not matched to the increase in midrange airflow that now has occured once the exhuast backpressure has been reduced. His AFR is not even to redline anyway.

BTW the soft and hard rev limiters don't just cut fuel arbitrarily at redline. If it did the engine would sustain massive detonation. Fuel and spark are cut at the same time. You of course knew that right?


I have never heard of anyone ever putting FPR's in series. I am not sure why you would even mention it unless you have no clue as to what I am talking about. When someone says they are adding some 19" wheels to their E55 do you think they are trying to bolt them to the roof?


What are you talking about? These cars have more than one ECU fuel map for idle, partial load, high load, WOT, etc. The ECU meters the fuel on all of these maps. Adaptation can occur not only on part throttle but also open loop. I think every system since Motronic 3.1.1 is capable of this. We are not talking about swapping jets on a Holley 850.


On my race car I have an EGT on each manifold just beyond the exhaust port of the head. This is the ideal setup if the car is going to be run at sustained WOT such as in road racing. However it is not absolutely necessary on a street car. You can run one EGT on each bank to use the sensors not for fine tuning but as an idiot light. It is a pretty common practice. But you knew that already right?

Yes. You have exposed me for the idiot I am. Thanks for the re-education. It is not everyday that some random person attacks you on the internet and then goes on to "defeat" you with his "knowledge." I declare you the winner.

If anyone is interested in my backround, I slept at a Holiday Inn Express last night.

 

Do you realize how dangerous it is to ask me my opinion? Too late - get comfortable.

Lambda Sensor:
The O2 sensors in your vehicle are there for one purpose - to optimize the effect of the catalytic converters. They have nothing to do with power, mileage, or anything else that's not emissions related. There's no tuning to be had here.

Conversely, the O2 sensors on the dyno are your friends - that is, as you pointed out earlier, if they're properly calibrated. (This would be a good question for all of you to ask your local dyno shops.) You absolutely must use the dyno O2 sensor to know what your car's doing at WOT. You really don't want a melted piston to tell you that you're running too lean. Unfortunately, it usually takes custom programming to adjust for the sensor's output.

There are some exceptions. My youngest daughter has a '97 turbo Eclipse that has a bigger turbo, bigger intercooler, bigger injectors, bigger exhaust (see a common theme here?),downpipe, intake tube, turbo timer, and AFC. The AFC is a stand-alone computer that modifies the existing fuel curve w/o reprogramming. When we dyno'd her car, we were able to take an A/F curve that looked like a heart-rate monitor and turn it into a topographical map of Kansas, with a slight downward tilt towards rich. At 20 pounds of boost, she's putting down 275 HP at the front wheels. That's a power-to-weight ratio similar to a stock E55! If the E55 is a Beast, this thing is a Beastette. Know what torque steer is? I found out the first time I got on it in 1st gear - I almost drove into the curb. But I digress.

Summary: you need a dyno Lambda sensor to properly tune WOT.

EGT Probe:
This sensor has limited street functionality. If you're just going to use one (or even one per bank), it's redundant with the Lambda sensor. Even though the EGT probe is very accurate, they pretty much tell you the same thing - A/F ratio.

If you have the capability to put one on each exhaust tube and the capability to adjust the injector pulse widths individually, then you can tune to optimum power for your configuration. If you don't have individual injector control, you can also adjust each cylinder's temperature by changing the size/length of each header tube. But, Ohhh Mama, is that a lot of work - and what you determine to work probably won't fit the chassis. Have you ever seen pictures of engines running at WOT on an engine dyno with the lights off? The headers are glowing a reddish-orange color. And if you look closely, you'll see that each tube is a slightly different color. The lighter the color, the leaner the cylinder.

If you're really curious about your exhaust temperatures, but don't want to go through the hassle if installing separate probes, there are hand-held instruments that can measure the temperature from a short distance. They look a little like timing lights. And you can do all the cylinders quickly, so the readings would be relavent.

Summary: EGT probes are nice, but not necessary for street tuning.

Boost Gauge:
For the most part, this one is more of a golly-gee-whiz gauge on a day-to-day basis. Good for bragging rights. But be warned - I have put three boost gauges on an engine at the same time tee'd into the same vacuum line and they all read differently - by 2-3 psi.

Now having said that, they can be usefull as a diagnostic tool. Increased boost w/no mods could indicate a flow restriction somewhere. Conversely, reduced boost w/no mods could indicate an intake leak, blower going bad, etc. You really have to know what the boost level should be at various RPM points to use this gauge effectively.

To answer your question earlier in the thread: the maximum boost on an E55 should theoretically occur at all points in the RPM range. MB is using a Lysholm screw-type compressor in the car. Notice I said compressor, not blower. With this unit, the air is compressed before it exits and expands into the intake tract. Other superchargers (Roots, centrifugal, turbos), are just high-speed fans that blow copious amounts of air into the intake tract until boost builds. If the compressor is sized correctly for the engine it's attached to, then, with the standard pulleys, boost should be constant at the appropriate level. If it's not sized correctly - well, I'm not sure. But I suspect that an undersized compressor would still have constant boost, but at a lower level. You would have to spin it faster to regain boost. The opposite for sized too big.

Summary: boost gauges are nice lo look at, but have limited functionality for tuning - better suited for diagnostics.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~

IMO, the best way to tune for the street with limited resources and dyno availability is 1/4 mile trap speed. This is an excellent indicator of HP. By knowing the weight of the vehicle and this speed, you can calculate HP. In fact, there are web sites where you just plug in these two numbers and it spits out HP. Like this one:

http://www.ajdesigner.com/phphorsepo...horsepower.php

Don't have access to a dragstrip? Well have I got a deal for you. The Gtech-Pro Model SS. For 200 bills, this little baby will tell you everything about your car's performance. Go here for details:

http://www.gtechpro.com/ss.html

And for another 100 bills, you can get the model that acts as a data logger that can be downloaded into your computer. Go here:

http://www.gtechpro.com/rr.html

Here's a site for elevation correction:

http://www.smokemup.com/auto_math/nh...on_factors.php

Once you get 1/4 mile speed, adjust for elevation, and convert to HP, you can compare to other members' cars. You can also use it to validate dyno runs. Please note: this is crank HP.

As an example: for a 4300 lb car in Denver with an elevation of 5000 ft, if your trap speed is 105 mph, after elevation correction it will be 112 mph, plug it into the HP calculator and you get 471 HP.

For those of who already have trap speed and dyno data, how about starting a new thread with your results and then we can do some comparing.

 

If the W211's are anything like the W208, then we have a returnless FPR which is integral with the fuel filter.

 

eclou it definitely is returnless, good idea to check the fuel filter. It's not on the fuel rail or at least I can't see it. Maybe one of the guys from evo or kleemann can comment.

 

This makes no sense at all. The O2 sensors built into our cars are are designed to do both. The pre-cat sensors are there to protect the cats from premature failure by excessive fuel prior to the cats heating up to efficiency. The air injector pump is triggered to help heat up the cats. The information of the pre and post cat O2 sensors are compared to maximize fuel efficiency and reduce emissions.

The main reason that dyno sensors are preferred is b/c they are 5 wire and not 3-4 wire systems and react far more quickly. There is usually too much dithering in a 3 wire system to aid in accurate tuning.

The S-Apexi is capable of fine tuning the fuel metering under different loads. It works very well on my 951. But a properly tuned AFR for a turbo is not going to look like the map of Kansas. If yours looks that way then you are sacrificing low end spool-up.

By this reasoning we should have one O2 sensor per cylinder as well.

I have never heard of altering primary or secondary exhaust header lengths to adjust EGT. That makes as much sense as removing ones tonsils thru an incision on the foot. Exhaust manifolds are custom manufactured to produce equal flow on a flow bench.

Yes, while running the 1/4 mile I will open the hood of my car with my robotic arm to check each exhaust primary with a pyrometer. Nice.

Lysholm/twin screw type compressors are capable of building max boost very early and hold the boost constant. This is true until heat soak sets in. At that point the intake charge is so heated that the density cannot be maintained and boost is lost. You cannot just spin a compressor faster and regain boost, there is only a certain range of efficiency.

This will work but some of us "posers" would prefer not to just "let 'er rip" to see if everything is working correctly. Hey guys, watch this....

 

[QUOTE=vrus] massive 295 rears wiggle the rear end and it takes off like a rocket. I am hooked big time...
QUOTE]

Not to go off topic, but this interests me. The wiggle you have... has it always been there, or do you attribute it to more power? I'll tell you why...

I'm bone stock. When I went with my Kinesis 19s and 295s, we checked every which way for fit. It only barely touched when the car was completely off the ground, on the insdie... once lowered, all clear.

But I noticed a wiggle. Punch it off the line with traction control and you'd feel the thing literally pushing on one side, then the other... but just slightly. Everyone noticed. I look under there time and again and only see the lightest of scuff marks. It was actually kinda fun... until I realized it was habitual.

this all happened right after going to the 295s. My theory is that under hard acceleration the rear end compresses enough so that the inside edge of the tire barely rubs the inside of the plastic wheel well... enough frition to either a) momentarily trigger braking on the other side to compensate or b) make it wiggle as each side reaches a balance and the car lifts back up.

I'm about to throw on the stock tires again just to see. What is fascinating about all of this is that you'd THINK I'd have some noticable marks on the tires or the wheel well. Nothing I can see much of, so I have to take it all off and answer my own question.

But from what Brandon at Kleemann said, there should be zero wiggle... they generally just go smooth and straight the whole time.

Maybe your use of the word has nothing to do with my problem, but boy did it catch my attention... wiggle and 295.

Regards,

Loren

 

There it is... another 295 user with a wiggle... two is company, 3 is a situation...

Guys... is there something I'm supposed to know about 295's making your car slightly fishtail / wiggle on launch?

Thanks,

Loren

 

Or you can get a stand alone wideband setup. I use the Dynojet Wideband Commander, but there are a bunch out there.

http://www.widebandcommander.com/

I don't agree with your conclusions on the stock O2s, either. This is based on my own ECU tuning experience using various tools available to tweak GM ECUs.

 

Hi Loren,

The word "wiggle" I used was to describe a very slight fishtail when driving in an aggressive manner. The more aggressive I get with the throttle the bigger the wiggle/fishtail..

I wanted to try 295 on the rear because I wanted something that would fill the wheel well.. I knew full well that a 295 tire should not be mounted on a 10" wheel.. It should be on a 10.5" or 11" wheel. But, I also like the fact that there is enough sidewall to protect the lip of the wheel. I know that some of this "wiggle" can be attributed to the sidewall bulge/flex because of being mounted on a smaller width wheel but I don't know how much is because of it.

I think that on my next set of tires I will go back down to a 285 series on the rear. Michelin PS2 tires are generally wider than other tires so a 285 in a PS2 is probably the same width as a competing 295 tire from another brand.

That's my $0.02 anyways...

 

uh..........................someone please remind not to start ANY conversation on engine management, how to build race motors, etc on the next AMG meet. You guys are talking about things that most Mercedes Mechanics don't know ( they plug in and read the fault codes or listen to the noise............then look for bulletins on previously documented problems via Mercedes database)

Grumpy666.............do you frighten little children? :v

do you take enjoyment when someone falls? :v

is it funny to you when they get hurt? :v

YES!..............I see...................

Do you hear voices...........like voices that tell you to kill people? :v

Does Holy water burn your skin? :v

Does the Excorsist make you laugh? :v

Help is available............first........ DESTROY YOUR BMW............and email us back on the results of your state of mind.

 

THANKS... I'm thinking the same thing... I mean sometimes the wiggle turns it to all out sailing... I think I'm going to 285s or 275s again myself...



Loren

 

Congratulations! In one short post you managed to demonstrate to the rest of the forum that you have nothing intelligent to say. But, to be fair, I searched and read several of your previous posts. Damn! You truly don't have anything intelligent to say. Your parents must be SO proud.

 

vrus, will you still stick with the 255/35/19 up front or go down to a 245/35/19?

 

AMGDriven,

That was uncalled for. Grumpy666 is a good contributor to the forum. He has alot of knowledge and when someone posts something that he doesn't agree with he debates it. No harm in that. You can't learn if you can't debate it out with others.

 

Unfortunately, the 2 go together. A 255/35/19 in the front with a 285 in the back would end up having a taller front tire. That would throw off the ABS and other traction computers. Therefore I would have to reduce the front to a 245 series.

To be honest, from trying this out, I would have to say the best OVERALL tire set for this car is a 245 front and 285 rear on a 10" or a 275" rear on a 9.5".

 

That's the point 666........................having fun at your angry, in your face, abrasive self...........................I read your posts too.......................always in someone's face telling them they don't know what they are talking about. Hell.................some apologize on upsetting you..just to shut you up!

If you read my post 666....................I even state I don't get as techanical as some........................but................... .........I will stay on this forum to make fun of a$$holes who don't know when to lay off

Flip side to this.....................I enjoy the abuse myself

 

VRUS..........................you have given tons of info in your quest..............it keeps a lot of us at the edge of our seat! I'm simply stating that GRUMPY666 comes across a little.........well..........GRUMPY. Good contributor or not...........no need to be an a$$.