Custom exhaust power gains?
01-26-2009, 10:05 AM
#51
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IMHO I find The oem exhaust manifolds are so restrictive, No matter what I did ,I could not get my N/A motor to respond to my expectations, at lease until the Kleemann headers were install. Then Bam! a 29 Ftlbs rear wheel increase of torque at low & mid rpm band, So it being said that both motors ( N/A & FI ) are running in a N/A state of operation there would be little or no decrease in torque or hp. And the FI motor would really begin to shine when the kompressor gets engaged.
Good to hear PTE! I'm ordering the kleemann headers/downpipes early this week!! I will then have some dyno data on a full custom exhaust, which I believe is very similar to the W208 system, at least identical from the heads to the cats. The headers will be mated to my current 200cell stainless cats, no reso, and 3in mandrel stainless all the way back to a stainless open maganflow all following the OEM path but 1/4in larger diameter. It sounds and looks awesome but I'm certain the bottle neck OEM manifolds/primary cats have held back any power increase the system I had made creates. I would expect to have these if a few weeks maybe, then I should have some dyno #'s.
01-26-2009, 10:09 AM
#52
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2003 E55 AMG
Just to add on to this post.. YES. I did install and remove a 3" exhaust system.
I think I've tried more exhaust combinations on my car than anyone else on this board. I was searching for the best combination to offer the right sound, the right power, and the right look.
At the time I tried the 3" setup I was only making 490rwhp. I felt it took away too much torque and the car wasnt as fun to drive from "stoplight to stoplight".. The highway pulling power was substantially better but at the time it was overkill for my setup so I went back to a 2.75" setup with a pair of high flow catalytic converters.
Choosing the right exhaust setup is really dependent on what power level you are at. In my opinion if you are under 500rwhp stepping up to a 3" will sacrifice alot of low end grunt. If you are interested in 1/4mile times and highway racing only then this is ok. If you like the torquey feel of the 55K motor then I would stick with 2.75" under 500rwhp.
When you are making 570rwhp or more having the 3" setup is a must.. Car makes way too much torque and just lights up the tires in 1st - 3rd gear. Giving up that lower end grunt and moving the power band up is a good thing.
I think I've tried more exhaust combinations on my car than anyone else on this board. I was searching for the best combination to offer the right sound, the right power, and the right look.
At the time I tried the 3" setup I was only making 490rwhp. I felt it took away too much torque and the car wasnt as fun to drive from "stoplight to stoplight".. The highway pulling power was substantially better but at the time it was overkill for my setup so I went back to a 2.75" setup with a pair of high flow catalytic converters.
Choosing the right exhaust setup is really dependent on what power level you are at. In my opinion if you are under 500rwhp stepping up to a 3" will sacrifice alot of low end grunt. If you are interested in 1/4mile times and highway racing only then this is ok. If you like the torquey feel of the 55K motor then I would stick with 2.75" under 500rwhp.
When you are making 570rwhp or more having the 3" setup is a must.. Car makes way too much torque and just lights up the tires in 1st - 3rd gear. Giving up that lower end grunt and moving the power band up is a good thing.
Good to see some knowledgeable forum members exchanging opinions on exhaust flow, which is by no means a simple concept.
To the original poster: Victor from VRP built a full 3 inch exhaust a while back for his car and the loss of torque in the low RPM range was significant enough for him to take it off. Without getting to deep into the exhaust flow discussion, what MR AMG is saying is true within a certain context - that context being ultimate power. However, as with many considerations, total flow is not always the path everyone really wants - and while for the most part the more flow the better, remember there is often a price to be paid. IN this case, with a super high flow exhaust system, sometimes throttle response can become the collateral damage.
Cam specs can have the same pros/cons... the more aggressive you make a cam profile, the more adverse effects it can have on everything from idling to throttle response and power band. It's not always as cut and dry as physics would lead us to believe.
Just my $.02
-m
To the original poster: Victor from VRP built a full 3 inch exhaust a while back for his car and the loss of torque in the low RPM range was significant enough for him to take it off. Without getting to deep into the exhaust flow discussion, what MR AMG is saying is true within a certain context - that context being ultimate power. However, as with many considerations, total flow is not always the path everyone really wants - and while for the most part the more flow the better, remember there is often a price to be paid. IN this case, with a super high flow exhaust system, sometimes throttle response can become the collateral damage.
Cam specs can have the same pros/cons... the more aggressive you make a cam profile, the more adverse effects it can have on everything from idling to throttle response and power band. It's not always as cut and dry as physics would lead us to believe.
Just my $.02
-m
01-26-2009, 10:23 AM
#53
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Thread Starter
Thanks for the tip on dynoing, I will try it next time
Well I believe the current setup is dual 2.375" pipes to a y and a single 2.75" pipe back to the eisenmann muffler. The W208 does not have dual exhaust. But that can be changed. It seems like the consensus is to run dual 2.75" pipes all the way back but I was told it is difficult to find 2.75" piping. I will probably throw an x-pipe in there too. From what Victor is saying, dual 3" would be overkill. Either way, I plan on keeping the current exhaust for a little bit and going back to it if I dont like th enew setup for any reason. I just need to find time to drive up past Philly and drop my car off. Would I need a retune after this as I would suspect this changes the afr? Thanks for all the help guys
Well I believe the current setup is dual 2.375" pipes to a y and a single 2.75" pipe back to the eisenmann muffler. The W208 does not have dual exhaust. But that can be changed. It seems like the consensus is to run dual 2.75" pipes all the way back but I was told it is difficult to find 2.75" piping. I will probably throw an x-pipe in there too. From what Victor is saying, dual 3" would be overkill. Either way, I plan on keeping the current exhaust for a little bit and going back to it if I dont like th enew setup for any reason. I just need to find time to drive up past Philly and drop my car off. Would I need a retune after this as I would suspect this changes the afr? Thanks for all the help guys
01-26-2009, 04:03 PM
#54
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2001 clk55 AMG
Just to add on to this post.. YES. I did install and remove a 3" exhaust system.
I think I've tried more exhaust combinations on my car than anyone else on this board. I was searching for the best combination to offer the right sound, the right power, and the right look.
At the time I tried the 3" setup I was only making 490rwhp. I felt it took away too much torque and the car wasnt as fun to drive from "stoplight to stoplight".. The highway pulling power was substantially better but at the time it was overkill for my setup so I went back to a 2.75" setup with a pair of high flow catalytic converters.
Choosing the right exhaust setup is really dependent on what power level you are at. In my opinion if you are under 500rwhp stepping up to a 3" will sacrifice alot of low end grunt. If you are interested in 1/4mile times and highway racing only then this is ok. If you like the torquey feel of the 55K motor then I would stick with 2.75" under 500rwhp.
When you are making 570rwhp or more having the 3" setup is a must.. Car makes way too much torque and just lights up the tires in 1st - 3rd gear. Giving up that lower end grunt and moving the power band up is a good thing.
I think I've tried more exhaust combinations on my car than anyone else on this board. I was searching for the best combination to offer the right sound, the right power, and the right look.
At the time I tried the 3" setup I was only making 490rwhp. I felt it took away too much torque and the car wasnt as fun to drive from "stoplight to stoplight".. The highway pulling power was substantially better but at the time it was overkill for my setup so I went back to a 2.75" setup with a pair of high flow catalytic converters.
Choosing the right exhaust setup is really dependent on what power level you are at. In my opinion if you are under 500rwhp stepping up to a 3" will sacrifice alot of low end grunt. If you are interested in 1/4mile times and highway racing only then this is ok. If you like the torquey feel of the 55K motor then I would stick with 2.75" under 500rwhp.
When you are making 570rwhp or more having the 3" setup is a must.. Car makes way too much torque and just lights up the tires in 1st - 3rd gear. Giving up that lower end grunt and moving the power band up is a good thing.
02-13-2009, 02:04 PM
#55
Out Of Control!!
Thread Starter
Just an update: BlackonBlackCLK made me a custom dual 3" setup from the headers all the way back. Unfortunately the resonator wouldn't fit in the tunnel so Its just straight pipe to an x-pipe back to 2 mufflers mounted sideways and tack welded together. It is WAYYYYY too loud lol
02-13-2009, 02:20 PM
#56
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Mercedes
Just an update: BlackonBlackCLK made me a custom dual 3" setup from the headers all the way back. Unfortunately the resonator wouldn't fit in the tunnel so Its just straight pipe to an x-pipe back to 2 mufflers mounted sideways and tack welded together. It is WAYYYYY too loud lol
02-13-2009, 03:18 PM
#58
Out Of Control!!
Thread Starter
Unfortunately I hato pull the trans and send it back to be rebuilt again. But it shold be back and in the car by next weekend and I will make video clips. It is rediculously loud. I started the car and my mailman jumped 5 feet!
02-25-2009, 03:00 AM
#59
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Mercedes,Porsche etc
what you need to do to quiet the car is the following,,
if AMG car you have
cheaper method
keep 3 inch pipes and
put RACING cats in high flow 200 or 300 cell
put X-pipe MIDWAY in the exhaust..
put 1 slim high flow bullet type resonator tube style after X-pipe but before muffler
on EACH PIPE -see style here
http://www.hottexhaust.com/detail.asp?PRODUCT_ID=10435
they will fit, have them on my merc..
IDEAL METHOD for quieting the car
keep 3 inch pipes you have merge them into 3" X pipe with 2.75 " pipes After rest of the way back- this will not hurt performance, and quiets it down
put
put RACING cats in high flow 200 or 300 cell
put X-pipe MIDWAY in the exhaust..
put 1 slim high flow resonator tube style after X-pipe but before muffler on EACH PIPE
IF car NOT AMG
keep 3 inch pipes you have merge them into 2.75" X pipe with 2.75 " pipes rest of the way back- this will not hurt performance, and maintains enough backpressure and quiets it down
then put
put RACING cats in high flow 200 or 300 cell
put 2.75" X-pipe MIDWAY in the exhaust..
put 1 slim high flow bullet type resonator tube style after X-pipe but before muffler on EACH PIPE
that should make the car sound way better, not hurt performance at all,
and make it about 15db quieter and sound smoother..
Last edited by storm; 02-25-2009 at 06:07 PM.
02-25-2009, 03:30 AM
#60
MBWorld Fanatic!
Yeah blackbenzz, It IS the same for all FI motors. I have posted this MANY time int he past under other threads. Numerous companies have also backed this up like Vortech, KenneBell, etc. If you are forcing, aka pressurizing the intake track, you DO NOT want any back pressure, or need it. Check out their web sites for the full details my friend.
See yeah
PS: My KenneBell stang running 10 pounds of boost had JBA shorties, MAC box x pipe, flowmaster 40 eaxhaust, which when swapped from the stock cats dropped my 1/4 mile times by over .6 seconds. Nice gain. Yes I know it was a Ford, but an engine is an engine here guys.
See yeah
PS: My KenneBell stang running 10 pounds of boost had JBA shorties, MAC box x pipe, flowmaster 40 eaxhaust, which when swapped from the stock cats dropped my 1/4 mile times by over .6 seconds. Nice gain. Yes I know it was a Ford, but an engine is an engine here guys.
Last edited by Max.H; 02-25-2009 at 03:35 AM.
