About how much horsepower would a mild cam add? along with new lifters? and changing my stock exhaust to a 3inch from the stock headers back?

 

2-4 hp.....

Just kidding, it all depends on the specs of the cam, and as far as the exhaust goes, the sock manifolds are a killer, even if you put a 3 inch exhaust on the car. Save your money and get some headers first, then the rest.

 

I would also have to add that the 3in exhaust is a bit big for our engine. Headers and a 2.5in exhaust(Dynomax SuperTurbo cat-back...just throwin that out there) would probably be your best bet. Youll end up losing back pressure and you torque will suffer (I believe thats how that goes).

 

People overuse the term backpressure. Backpressure is just that- a restriction. Does nothing to help power. What you're looking for is proper exhaust velocity with the least flow resistance. Unfortunately it requires lots of complicated math or a simulator I don't have acess to to figure out what that would be sooo... 2.25 to 2.5 (single into dual exit) with a freeflowing muffler would probably be in the ballpark.

We tend to harp on the benefits of a good exhaust alot, but that's really the best palce to start with these engines. Then the heads/intake, then the cam, ect.

 

Second on the exhaust. You need to be able to get the spent gases from the combustion chamber out before you can force more in.

 

and how do you do that? not to sure?

thanks for all the fast replies

 

A few minutes with a hacksaw would help this out a lot...

Selecting exhaust with appropriate diameter would help, as well as removing restrictions from the exhaust, such as lots of bends, twists and curls, as well as a muffler that doesn't restrict exhaust as much. Usually a decent brand name exhaust will have been designed with all of this in mind.

 

I was looking at a cam too, but headers are a 'no-go' here in California for the 3.1(smog). Is it worthwhile maybe getting the stock manifolds extrude honed to at least open them up a little?

 

Waste of money. The stock log manifold is about as crappy as it gets.

 

So no way to upgrade the exhaust on a 3.1 in CA? I already have a catback...

 

Get a highflow cat. I read somewhere that you could make the smog pump work with headers with some modification.

 

I think in CA you need a CARB number...so modification to the headers wont work.