LS exhaust suggestions

[glassman]

Hey all, so my LS conversion hit a bump in the road. Everything was kinda dialed till i put my new/old exhaust system. New meaning it was installed behind my sbc in April of last year, 2.5 pipes and Magnaflow with turndowns. So we cut it and welded on the Dynatech header adapters then the car ran like sh!$. My tech/friend thought it was in my head, and he said drive it uncorked, we'll we did. Huge differrence. He measured the backpressure with a guage through one the of O2 sensor holes and it came up with 7, he said anything above (?) was too much and we're like double that.

What type of crosspipe recomendation?
We were told a need of some backpressure is required, so we went 2.5.

Runs good now, uncorked, but i cant leave it like that....or can i (hehehe)? JK

So suggestions for a kickass exhaust?

[IMPALA MAN]

Easy fix:
http://www.dynatechheaders.com/m_camaro_67_69.html

Dynatech offers a 3.00" system.

[WSSix]

What size and build of engine? Dual 2.5 inch exhaust supports a lot of power. 3 inch may be too big. It could be the routing and the bends not the size of the pipe.

[Vince@Meanstreets]

Originally Posted by glassman

Hey all, so my LS conversion hit a bump in the road. Everything was kinda dialed till i put my new/old exhaust system. New meaning it was installed behind my sbc in April of last year, 2.5 pipes and Magnaflow with turndowns. So we cut it and welded on the Dynatech header adapters then the car ran like sh!$. My tech/friend thought it was in my head, and he said drive it uncorked, we'll we did. Huge differrence. He measured the backpressure with a guage through one the of O2 sensor holes and it came up with 7, he said anything above (?) was too much and we're like double that.

What type of crosspipe recomendation?
We were told a need of some backpressure is required, so we went 2.5.

Runs good now, uncorked, but i cant leave it like that....or can i (hehehe)? JK

So suggestions for a kickass exhaust?

2.5 should be adequate. If your getting 7 i'd say pull the racoons out of your pipes. OR replace your mufflers.

[Musclerodz]

how big of motor? your exhaust should not be restricted unless you have something taking residence in your exhaust system

[Ron Sutton]

Originally Posted by Vince@MSperfab

2.5 should be adequate. If your getting 7 i'd say pull the racoons out of your pipes. OR replace your mufflers.

Them gosh darn raccoons.

.

[Ron Sutton]

Originally Posted by glassman

Hey all, so my LS conversion hit a bump in the road. Everything was kinda dialed till i put my new/old exhaust system. New meaning it was installed behind my sbc in April of last year, 2.5 pipes and Magnaflow with turndowns. So we cut it and welded on the Dynatech header adapters then the car ran like sh!$. My tech/friend thought it was in my head, and he said drive it uncorked, we'll we did. Huge differrence. He measured the backpressure with a guage through one the of O2 sensor holes and it came up with 7, he said anything above (?) was too much and we're like double that.

What type of crosspipe recomendation?
We were told a need of some backpressure is required, so we went 2.5.

Runs good now, uncorked, but i cant leave it like that....or can i (hehehe)? JK

So suggestions for a kickass exhaust?

How much power is your LS engine building ? and at what max rpm ?

[glassman]

Right now it is a stock LS1 from an 04 Gto, so i'm guessing right around 400 ponies with the long tube Dynatech's and an 85mm throttle body (brain fartin on the right word).

My goal is right around 540 at the crank, heads and cam are in the works.

I'm also having some computer software difficulties using the GTO computer, theres apparently some switching difficulties between the traction of an automatic computer vs manual, well we've made the changes and the car will still stall doing a 180* or donut....to be determined...

[hifi875]

2.5 inch is more than adequate for your power

[Musclerodz]

exhaust is not your problem. plenty large enough to handle your motor.