Every time an aftermarket company, race team or OEM maker wants to add power to a car, they change the intake and exhaust to "reduce back pressure". Yet there are always nay sayers that exclaim that no significant power can be made this way. If that is so, why is this always the first step in modifying any car. I just read the Excellence article on the Gemballa CGT and again they mod the exhaust to lessen back pressure and gain a claimed 53 BHP.

I know this subject has been beat to death, so forgive me....just had to vent

 

I put Fabspeed mufflers on my 2006 C2S. I can not feel any difference in power but the car sure does sound nice! Fabspeed claims around 8-10hp with mufflers but that is not an increase enough for someone to feel. It takes around 50 or so HP before you can really tell a difference in feel on the street.

these manufactures calims these HP ratings for sales and to try and stay competitive with in their industry.

 

I agree - I've been putting aftermarket exhaust systems on various cars for years and I never bought one for the HP claims - sound and looks drove my buying decisions.

 

Actually you could probably feel a honest 10hp, it won't be eye opening but you will notice it. Anything under this you probably won't.

Dave

 

No, I don't think I can. I only drove my Porsche for a minute before the Fabspeed mufflers and can't tell anything really. I think it might rev faster and above 5k rpm it really sings!

I have had a lot of C4 and C5 Vettes and have done intake and exhaust mods with before and after dyno's and had 10-20hp increase and it was real hard to tell any difference if feel on the street. I have done mods on Vettes for 50hp and I can feel a difference.

 

Anything that reduces backpressure will increase HP and mildly sacrifice low end tq. You should add an intake to fully reap the benefits though. The naysayers have never had an engine on a dyno I would imagine.
As you know, fabspeed sells excellent stuff.

 

My butt dyno must be more sensitive than yours .

Dave

 

i'm installing AWE exhaust system this spring and an EVO cold air box. I'll probably have the ECU massaged as well, then I'll be venting.

 

This is generally true and why race teams will typically do it. Race engines spend the majority of their lives in the upper RPM range, where exhaust swaps tend to add horsepower. Daily drivers tend to spend the majority of their time in lower RPM ranges, where the engine will suffer slightly. The exhaust swap HP increase is only really good for dyno bragging rights (i.e. peak HP) with your friends.

 

I've been considering AWE and Fabspeed for my 997S with the X51 and from what I gather, the exhaust on the X51 is pretty much rock solid - and with the baffles open sounds great (but not like an aftermarket - hey, I live in Connecticut) - I'm going to massage the ECU as well since I think that is truly where some real torque gains can be made.

 

I believe the X51 already has different/better headers that non-X51 engines so I wouldn't change headers. As far as mufflers and cats, personally I'd leave stock. I like being able to turn PSE on/off as I want.

 

I doubt that a slightly less restrictive muffler ( 2 or 3 hp at most ) makes your car rev any faster than stock .
And every car "sings" above 5k rpm. It's due to the air intake resonator closing , not the Fabspeed cans .

 

What is meant is that with the fabspeed mufflers it sounds (ie sings) really good above 5k rpm. I put in a BCM air filter too so that help in the sound department.