exaust..

i have those open headers on my 350, now once i ditch the full lengths and put a shorty that i got from hedman 1-5/8 to a 3" collector. should my e.t's improve and my tourque band improve with them in with exhaust out the back instead of ugly open headers? the car should be much faster, cruise at low rpms especially with the 3 speed tranny. what should i expect over the open full lenghts?

with the shorty headers and collector youre going to lose some torque and gain some hp, power band is also going to move up in the rpm range.

Is there some science to what certain length headers, and other different exhaust mods affect a car's performance? Can you give me some examples? Like how with shorty headers the power band will be at higher R's?

When you switch to short tube headers from long tube headers you actually have slight GAINS in horsepower and torque. But your power curve does not last as long so the car actually feels a tad slower.

Rob

Is there some science to what certain length headers, and other different exhaust mods affect a car's performance? Can you give me some examples? Like how with shorty headers the power band will be at higher R's?

yes, its called fluid dynamics, kinematics, harmonic motion, and thermodynamics. ill give you a lecture next semester when i complete my physics minor...

Ok, sounds good Chevyracincamaro. I'll look forward to that... Thanks

Frankly if headers are the only mod on the car, you may not feel anything. It's the 1st thing I did many years ago on my Z-28 and it was underwhelming.

You got the right headers though 1 5/8- 1 3/4 with 36" primaries into 3" collectors is best for street. While you're on exhaust make sure you have at least 2 1/2 pipes with a crossover pipe into low restriction muffs of choice. If your exhaust is pretty ratty go new 3- 3 1/4"
http://www.animationlibrary.com/Animation11/Transportation/Cars/Scene_from_50s.gif

As most of them already said and as alot of posts go on the forums.

Headers are only a part of the system. Remember your engine is like your lungs. Inhale and exhaling.

Inhale - intake. Cold Air or Ram Air intake.

Throttle Body - your Esophogus (Long tubepart between mouth and lungs) but its not as long. Point is, bigger it is, more air you can get from your CAI/RAm Air

Headers. Semi-same thingas your esophogus bigger they are better flow since you already have alot of air coming in, gotta get alot out now.

Exhaust - mouth kinda Less restrictive and more flow is better hp/torque/mpg

:) Hope that good enough anatomy session for you. Good luck.