MB_Forever

Not sure if you guys saw this... I didn't notice it until yesterday: apparently the always-controversial discussion about long-tube header design for the C63 has continued over on the Benz Boost website....

I would've thought something like this would be easy to prove one way or another: dyno both types of headers and see which one makes more power or take both headers to the track and run them both back to back it shouldn't be too hard of an R&D project for even small companies to manage

In terms of drivetrain reliability, brad had a valid point.... maybe too much torque is not good for our tranny? Is there any type of research done on this to prove/disprove? We may have to wait a few years before passing judgment on this.

I've read the vendors arguments, but I'd like to hear some thoughts from you guys, regular owners/members on this site about this? I don't want to pollute the thread, so I specifically would like to hear non vendors opinions about this? Vendors are welcomed to post comments as members not as endorsers of any products. Any input would be greatly appreciated

_AMG_

I agree, the best way to resolve this issue is to run the cars heads up.

LZH

Regarding the increased torque from a certain header design eating up transmissions...I just don't see how that's possible considering the torque limiting software in the 722.9. From what I understand, you could throw 1000 lb/ft of torque at it and it would just dump the additional power via the software. Sure something is gonna take a beating; most likely the torque converter and then the clutch packs as evidenced by the few failures that we know about - but those were both under pretty abusive circumstances IIRC. And furthermore, it sounds like the actual gearbox itself is protected pretty well allowing other consumable/less expensive parts in front of it to take the failure and preserve the most expensive components.

MB_Forever

Hmmm..... that's a very good point. In a case of high torque, the TCU software should be able to easily interfere and cut the torque back to an acceptable amount.

Playing devil's advocate here.... why didn't interfere enough in DadsC63's NOS case though? Is it limited to how much torque it can govern?

bhamg

+1 with everything said here. And as for a personal preference for a car that is a DD, I go for torque every time.

Papachristou

with handbuilt engines, each car is unique. Your process is flawed. You would need to find two cars that dyno'ed close to the same number in stock form...

Even Money

It depends on your preference, i.e., what do you want out of your headers? Because if it's based on 1/4 mile results there really is no controversy..

MB_Forever

Either that or install each header on the same car and dyno before and after or track the car before and after. I guess what I'm after is which header is best for performance? There are plenty of data from different cars right now showing that the 4 into 1 "may" indeed produce more power since the results have been replicated on different cars using the same aprts, but what about reliability and durability of the drive-train? Could we be sacrificing a lot of reliability for increased torque - especially on an-already-fragile tranny?

dodger63

I can change airboxes and wheels at the track to test same say but headers would be a challange! It would have to be a warm day but then again the 5 hour difference in the conditions of the day would probably be more then the difference in power u guys are talking about?

RStevens63

Let's take a look at the objective data provided by members on this forum alone:

Track: 1/8th mile, 1/4 mile, Standing mile.

VBox: 0-60, 0-100, 60-130mph.

Dyno: Who cares.

One header design holds the records for all of the above, and it's a 4 into 1 design.

Other attributes of the header design in question:

1) Longest primarys of any header on the market, this is necessary to build torque which is exactly what the doctor ordered for any N/A application. We all know M156s are torque deficient compared to the M113 and M275s, obviously we don't have twin turbos or a twin screw so we need all the help we can get to get these relatively heavy cars moving.

2) Correct primary diameter, 6.2L revving to 7000rpm requires a 1 7/8" dia tube.

3) High quality merge collectors with proper reduction, cone shape & size as well as construction (spun 316).

As has been stated previously, N/A performance is 100% about airflow velocity. Velocity in and out of the motor. You cannot build velocity with a Tri-Y anywhere near the order you can with a properly sized high velocity cone/spike merge collector as found in a properly setup 4 into 1.

I think that pretty much covers the basics of why the headers in question have proven superior in objective testing.

Now we have to take into account the execution of the design, aka fabrication quality of the headers.

Things worth noting vs other offerings from other manufacturers:

As discussed in superlubricity's excellent header comparison sticky, every other manufacturer of headers uses pre-bent 30, 45, 60, 90 degree bends to make their headers, they are not bent specifically for the design in question.

Hence each of the non parallel cut and weld's, also known as cheated bends or welds, kills flow throughout the primary. Some headers on the market have upwards of 10 non parallel cut and weld's per primary, so if one kills flow, what does 10+ do?

This distinction is highly important and the severity of the build quality issues is enough to taint this entire discussion alone.

Now as to the question as to whether or not one LT header design can make enough extra torque (vs another LT design, both catless) to destroy a 722.9 transmission: Absolutely 100% no way in hell.

In order to fry a 7G you're going to be applying 540+rwtq through it and the also weak factory converter on at least a handful of 1-4 gear WOT runs. If we look at the sequence of events as pertains to Dads car (thank you Keith for taking another one for the team) we can see this is not an isolated incident.

His first trans received 26,000 miles of abuse meaning 150+ 1/4 mile passes with subsequent burnouts before hand (using brakes not linelock), 3 standing mile events, open track events like Roebling Road and Sebring Intl Raceway, and of course whatever he did on the street. It wasn't until he sprayed the car with a 160 shot which increased TQ by ~100 lb/ft to the tires (he actually would have made more but the trans TCU limiters were keeping things in check) that the converter/trans began to slip. You can see this in the videos he posted as he was very open about the entire ordeal with his driveline issues. Even after the driveline was toast, the car still ran fine N/A however Dads made the smart decision to pull and replace both the converter and trans. After inspection it turned out both needed to be replaced, clutch packs smoked, fluid black as night. So they decide to go with a built trans with Level 10 clutch packs and a new converter. Within a few days (not even a week) with new upgraded trans hardware and only 6 passes with nitrous BAM another wasted trans.

So to make sure everyone's on the same page, a stock trans that lasted through 26,000 miles of abuse and still ran fine N/A even after it was damaged with nitrous, and a completely new and built trans were both smoked within days of adding power adder torque to the car.

Now for someone to even remotely suggest that a differently designed set of headers, albeit a superior design as admitted by the OP since they made so much more torque than their own design, caused a transmission failure or could have done so is simply ridiculous. No LT header will at 100rwtq vs another LT header at any rpm, let alone low rpm.

Further the additional comments pertaining to 4 into 1 designs were as follows, quotes taken from Superlubricity's header sticky:

1) Last I checked these were not 1.2 60' cars with proshifted trannys leaving the line at 9000rpm on slicks. C63s have 2.85 rear gearing, a 7 speed conventional auto with 2400rpm converter that only locks 95% at WOT. Driveline shock doesn't even begin to factor into the equation. Ever look at the driveshaft U-joint on a C63? The coupling is made of RUBBER. Shock that.

2) I'm really not sure what's meant by that statement, again if someone thinks headers are going to take a M156 to 540rwtq NA, well I have nothing else to say.

Look at any top of the line Corvette, Viper, Ford GT, GT500, whatever header and you can see that they are all 4 into 1 and none have erratic acceleration or electronics fighting the car. Additionally with all the 4 into 1 c63 header owners out there, has anyone heard of a single car with issues like this? None that I've seen. Just another ridiculous statement.

I see a lot of subjective marketing language and zero facts to back those statements. Where is the data? Instead of bringing factual numbers and data to the discussion we're left with "better/smoother".

Frankly if you take into account where the suggestion regarding header design being a potential culprit as far as Dads blown trannys, and also the subjective and flat out incorrect assumptions thrown out by the same individual that posted them, it's easy to see in my opinion why such statements were made. There is bias in this forum, and I'm far from the only one that see's it day in and day out.

RStevens63

Saying an engine is handbuilt really has nothing to do with it's performance potential. Modern tolerances are extremely tight, not even comparable to where they were 5 years ago. Moreover dynos are not the right place to test NA vehicles, no fans, no power. A c63 in 5th gear, 1:1, is going 184mph at redline, try and find any fans that can replicate that type of airflow.

Also if you've had a M156 apart, and yes I have, take note of the casting quality of the plastic/Mg intake manifold (flawless cannot even be ported) and cylinder heads and you'll get an idea of what I'm saying.

Thanks

c32AMG-DTM

Disagree about the Viper.

RStevens63

Haha, you are correct sir, 5 into 1, my apologies

dodger63

Haha took me a while and still didn't get it!?

superlubricity

4-into-1 on a Viper would create a very nasty exhaust leak on each side.

RStevens63

Yes but on the bright side it would keep torque down and the T56 intact (I kid I kid).

dodger63

My sin in the bathtub wants to no why I'm cracking up laughing right now

hhughes1

The 4 into 1 headers (MHP) dominate 1/4 mile results for C63's meanwhile dyno results for the same comparison group don't show the same significant difference. Why?? perhaps the 4 into 1 advantage requires the air supply that can only be obtained by a car actually moving at a high rate of speed, something a dyno can't replicate.

As to erratic tq delivery, I would strongly disagree. Although semi retired from the drags, I have driven plenty of road course miles during the past year. Power delivery is absolutely seamless, corner exits under WOT are an absolute blast and traction is easy to manage with the gas pedal. (Even easier as soon as my LSD is installed)

MB_Forever

That's another valid point that I've tried to make over and over.... the modern cars of today have electronics constantly monitoring and reacting to so many different variables/parameters all the time. It would make sense, therefore, to have a scenario where the dyno numbers don't match the track numbers and vise versa.

At first, I thought the whole "MHP" thing was producing good results only because they were using DadsC63's car. DadsC63 had all these little extra mods + weight savings + he was a very good driver, so I figured every little thing eventually helped that car to excel. But then, those good results started being duplicated on Dodger's car, Mthis's car, MHP's car, Religh63's car, harrower's car, etc.... it seemed as almost every 63 that got touched by MHP's parts became turbocharged

LZH

Bold above...people need to understand that after you spend countless hours at the drag strip, making a hundred or so passes, it gets pretty easy to lay down some really quick times. Drag racing is a skill that can be learned by just about anyone with enough practice. I think it's becoming very clear that the C63, with a few mods and a good driver yields some very quick times that can be duplicated over and over. Throw in some other weight saving mods and the times and traps improve drastically. Then, some track only prep like 100 octane tuned ECU's, drags, line locks and skinnys...and you have a mid 10 second car in the 130's. This isn't rocket science.

Mx_AMG

Torque is the actual work the engine is doing

http://www.revsearch.com/dynamometer...orsepower.html


, you have to keep it basic and remember that headers are just an outlet that delivers exhaust from the exhaust ports. While alot of other factors go into making them efficient (design, backpressre, exhaust pulse) , the design is an artform in itself.

GHAZAN

i thought every MHP header system comes with sneaky pete?

dodger63

To be honest I think a chimp could drive this car fast down the track. I think a complete novice that could listen to instruction would drive this thing fast! Also tune and fuel isn't track only in my opinion? Many cars run streets all day with fuel.. Not a DD obviously but sunny day cars?

dodger63

Actually the tune comes with a dictionary of drag racing cheats it's like a video game cheats book.

Dads C63

That's not nice to refer to Hagi as a "chimp"? Lol