Custom exhaust power gains?
#1
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Custom exhaust power gains?
Alot of people have tried different things with exhausts. I'm wondering how much power people have gained from doing a custom exhaust from the headers back. Mine is stock from the secondary cats back except for an eisenmann race muffler and I am considering running bigger diameter pipes all the way back to the muffler with no cats and was wondering if/how much power it would gain. Any input? I know on turbo cars you can make huge gains by removing exhaust restrictions, whats the deal with the s/c cars? It has been discussed before but if anyone has dyno gains to back up the claims that would be nice. 1/4 mile traps even better Feel free to discuss opinions/theory as well but try and back it up with at least some factual data
#4
Out Of Control!!
Thread Starter
^ You have a turbo car, it's a little different
Thanks for the advice Vadim . What do you think about dual 2.5" into a y-pipe and either 3 or 3.5" back to the muffler?
Edt: BlackonblackCLK has dual 3" all the way back so it will fit.
Edt: BlackonblackCLK has dual 3" all the way back so it will fit.
Last edited by blackbenzz; 01-21-2009 at 03:24 PM.
#5
MBWorld Fanatic!
I know...for you it's all about the right back pressure...somehow I have seen a few E55's putting on the Cut outs...maybe it's just for sound...
#6
I have heard bad things about cutouts on the internet. +
I always thought it would be a good idea if they were placed right before the first cats to have nothing blocking, kinda like dragster style. It would be only for racing tho... against z06's and such
I always thought it would be a good idea if they were placed right before the first cats to have nothing blocking, kinda like dragster style. It would be only for racing tho... against z06's and such
#7
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C55,SL55,C63
I have custom exhaust on my C55 I chopped on the resonator and secondary cats and picked up 12whp and like 18wtq. Then only to go with a cat back custom exhaust and gained an extra 5whp. Then I replaced my Primary cats with Random technology 300cell hiflow cats (no CEL issues at all) and gained 5whp. I have all the dyno charts somewhere.
Random Tech talked me into these 300cell cats saying they flow the same as 100cell cats without the CEL issues.
Random Tech talked me into these 300cell cats saying they flow the same as 100cell cats without the CEL issues.
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#8
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2001 clk55 AMG
I have custom exhaust on my C55 I chopped on the resonator and secondary cats and picked up 12whp and like 18wtq. Then only to go with a cat back custom exhaust and gained an extra 5whp. Then I replaced my Primary cats with Random technology 300cell hiflow cats (no CEL issues at all) and gained 5whp. I have all the dyno charts somewhere.
Random Tech talked me into these 300cell cats saying they flow the same as 100cell cats without the CEL issues.
Random Tech talked me into these 300cell cats saying they flow the same as 100cell cats without the CEL issues.
#9
MBWorld Fanatic!
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.
#10
Out Of Control!!
Thread Starter
I have custom exhaust on my C55 I chopped on the resonator and secondary cats and picked up 12whp and like 18wtq. Then only to go with a cat back custom exhaust and gained an extra 5whp. Then I replaced my Primary cats with Random technology 300cell hiflow cats (no CEL issues at all) and gained 5whp. I have all the dyno charts somewhere.
Random Tech talked me into these 300cell cats saying they flow the same as 100cell cats without the CEL issues.
Random Tech talked me into these 300cell cats saying they flow the same as 100cell cats without the CEL issues.
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.
#12
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look into DMH cutouts, they are very good. had it on my vw, they have a 4yr warranty on the entire thing too. i know several people that had DMH cutouts for 2+ years now without problems.
#14
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997TT, R8 V10+, G550, Plaid S
here is a vid of my vw with cutout closed and my friend's (who had qtp and then went to dmh) cut out open
http://ca.youtube.com/watch?v=HcaWwJqq0m0
#15
Senior Member
In my experience with cars in the past you actually lose a little HP and gain some torque with opening up the exhaust. I've never seen a HP gain with adding an exhaust. Granted, you add noise. That is the only reason I do it anyways
#16
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Thanks
But I dont want any more torque Hooleyboy said he gained 22whp
But I dont want any more torque Hooleyboy said he gained 22whp
Last edited by blackbenzz; 01-22-2009 at 07:11 PM.
#17
what prevents a E55 from having a 3 inch exhaust.
when we talk about clearance problems are you talking about the exhaust channel that runs under the car where a 3 inch pipe will not fit or hit.
when we talk about clearance problems are you talking about the exhaust channel that runs under the car where a 3 inch pipe will not fit or hit.
#18
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He was refrring to my car, a W208 CLK55. But dual 3" pipes has been done on a CLK55 and I think thats what I'm gonna do too. Dunno if I should go catless I dont want the stink
#19
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S600TT, R350
Forced Induction cars are a lot less sensitive to exhaust tuning. Since they have pressure source on intake side, the function of exhaust simply becomes to evacuate combustion and reduce backpressure as much as possible.
#20
Sorry but that simply is not true. Since you have almost zero overlap on the cam you really need to work on the exhaust scavenging to help clean out the cylinders.
#22
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You are 100% correct on a NA engine requiring a properly tuned exhaust to help pull the spent gas out of the chamber, however ALL FI cars are really a different issue.
See yeah
#23
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#25
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f/i or not, our cars DEFINITELY lose low end power without "some" back pressure...however, not to the extent of a n/a car. you can't just lump all f/i cars in the same category as turbo cars.