I just bought a stock 94 z28 camaro with the exception of a cold air intake. I recently bought a SLP loudmouth exhaust (Catback) and hypertech tuner. As I installed the exhaust, it feels like I lost power. Is there anyone out there that has a solution, or someone who experianced this same thing? It feels like there might be to much air flow, but im not sure. Maybe a muffler would do the trick?

 

ive heard that you can lose some low end with the loud mouth system. i dont know if this is true or not, but that might be your problem.

 

You may feel like you lost some low end torque, this is due to it being very free flowing exhaust, and you are creating less "back pressure" do a search on that. Anyway the torque just moved to the upper rpm band the power you lost down low just moved up to your top end so you gained there. So you really didn't lose anything. It just moved the power higher up in the rpm range.

 

I doubt you lost anything due to the exhaust..... the exhaust does not need back-pressure. That is a myth. It sounds louder at part throttle, so you expect the engine to produce power proportional to the noise level, but you are still only at part throttle.

I'd suspect the Hypertech may be the problem. I've seen dyno tests that showed a loss of power with the HPP "power tuning". To get any significant gains, you have to opt for the 160* t'stat and revised fan on/off temps. Take the "power tuning" out and see if it feels better.

And, short of having 1/4-mile times for the car with or without the LM, you'll never know if you gained or lost...... SOTP is not a reliable measure.

 

i have seen tests with loss of power even with those options, imo hypercrap

Fred your not questioning his a$$ dyno are you?

 

Thanks for all your comments, it really helped and was what I was thinking. The hypertech to me actually was a waste of money. What would you guys surgest to have a fast quatermile time?

 

mail order tune is usually up to the task, try pcmforless or trifecta

 

lets say the hypertech made it lose 5 to 7 horse, not something you will probably truthfully notice outside of a dyno, ill put a good ammount of money its in your head, the louder sound of the car compared to the old exhaust you had.