I'm going to do headers, hi-flo cat, and cat-back system on my T/A in the spring and I'm hopin to get about 20-25 HP out of the deal, but I'm wondering, will there be much torque gain from the exhaust system? If so, is it about the same as the HP gains? I know this will vary for different applications but I'm just looking for a general idea.

 

That targeted HP gain is just about right, if a little conservative. Not only will you see a HP gain, but torque will increase as well. The entire powerband will extend a few hundred RPM and peaks will occur roughly 500RPM higher.

Still running the stock crossfire setup?

 

I agree. You typically do not lose low end torque at all with a full exhaust upgrade. It is a common myth. The only reason you would lose power with these cars with an exuast is if you go too big (4"+ that murders scavaging) or if it puts your car out of tune. By that I mean the change in volumetric efficiency. Most FI guys will clame a loss in low end but that is only because they need some chip work to take advantage of the 10%+ gain in VE. You car should make more power at almost every point in the curve. If it doesn't you need to tune it so that it does.

 

yes, I'm still running the stock crossfire set-up. The car is all original ( except for my boyds) and only has 45,000 miles so I don't plan to do any major modifications soon. Also, I told someone else that I hoped to get 25 HP out of the deal and they told me that was a little high so I'm glad to hear that I could get more than that. I just want my "muscle" car to at least have 200 HP ( 175 stock ). But I'm also excited that I'll see torque gains, too. Thanks for the info.

 

oh yeah, about the tuning thing, would a Jet Chip take care of that? I don't really want to mess with a custom one and I can get the "module" from Jet Chip for like $159 for my car.

 

i dont think those aftermarket chips do much for you... gains are minimal and you have to use premium gas... anyone who thinks otherwise, don't be afraid to chime in; i could be wrong

 

You are not wrong. You are correct. Off the shelf chips are nothing short of garabge. They are a stab in the dark. They add timing and fuel blindly where it is not needed. It is a rip off in its purest form once you understand the tuning needs of the fuel injected 3rd gen.

 

so, what you're saying is that if I need to have some "tuning" done to take advantage of my exhaust system, I'll have to drive half way across the country and drop a pile of dough for someone to do a custom one?

 

not necessarily lots of LT1 guys get mail order tunes, Im sure there are people that can get you a mail order chip. You just let them know what you have done over stock and good tuners know where to add and so on. Good tuning on a stock car can yeild more power. Remember GM designed the chip for grandma and sonny to drive.

 

It will be hard to find a good mail-order tuner, mostly because of his CFI setup. They're quite rare in running condition, and are rarely modified. There is a PROM tuning board here, but CFI guys are basically non-existant. Contact Ed Wright of Fastchip, if anyone can help, he can!

And again, 25HP might be conservative. Most cars with lower HP outputs stock do not see large gains from exhaust work. Our cars are an exception to that, as the factory exhaust is VERY restrictive. Even the goofy looking stock CFI setup.

 

alright, I'll keep this info for the spring, but chances are I won't even have to have a chip done, right? just if I a notice a "loss" of low-end grunt...?

 

Correct, you don't need it. However, tuning the engine for the increased exhaust flow will yield even more power. Low RPM torque should stay roughly the same or even increase a little.

 

awesome... I can't wait for spring so I can get the 'ol girl out again and start the performance upgrades. Thanks for all the info guys :lala: