"Exhausting" education

[justwhatido]

\"Exhausting\" education

I'm installing Jeg's GM 350. Will put on new exhaust. I've been reading posts about exhausts systems and have questions.

Headers? Ceramic coated? Painted? or stock exhaust manifold?

Exhaust: dual or single? what diameter gives what result? I thought that the goal was the least back pressure and it seemed that dual 3" would accomplish that. But I've read posts that indicate it would be detrimental. You guys have been in this for a while, so how about some input?

/forums/images/graemlins/pimp1.gif

Fred

 

[k20]

Re: \"Exhausting\" education

On headers, ceramic coated will last the longest and look the best. The painted ones, the paint will flake off probably the first time you fire it up. However since you say you are putting a new motor in, if you pay the $$ for ceramic coated, you need to do the breakin with a set of stock manifolds or old set of headers because the heat generated during initial breakin will screw up the ceramic coating.

Exhaust, I like duals, dont really know why, but a dual system w/ 2.25 or 2.5" pipe is good, I run the 2.5 on my bbc, but i also had it on my sbc. If you go single you have less crap in the way under the truck, and if you go single I would say a 3" would suffice.

 

[tweaker]

Re: \"Exhausting\" education

i don't know about others here, but on my truck when i opened up the exhaust the top end grew(by this i mean the beast loved to rev it up). the down side is i lost the back pressure and now the low end is lacking. it's all cause and effect. take from here to give to there. do you need the torque or can you spare a little for a quicker rev. also on my tbi i noticed that with out proper back pressure it didn't want to idle well, so you may want to factor that in too.

 

[SkulzNBonz]

Re: \"Exhausting\" education

The header quetion is answered. As far as single or dual exhaust, a 3" single will give you similar performance to a 2.25/2.5" set of duals. Unless you're running an extremely powerful small block, 2.5" dual exhaust is the absolute largest you should go. Any larger and performance will be lacking. I am running a set of 2.25" duals, and couldn't be happier.

John

 

[ntaj*ep]

Re: \"Exhausting\" education

Try-y ceramic coated headers and no bigger than 2.5" pipe. IMO best setup for a slow wheelin' machine.......

 

[bigburban383]

Re: \"Exhausting\" education

I would stick with small tube headers unless your running big expensive free flowing heads. Sounds like your going to use stock heads, so 1 5/8 is plenty enough for the header tubes. Personally I would go with a single exhaust (3" minmium), I think it sounds better, but dual exhaust is easyer and 2.5" is enough.

As far formulas, to get optimal exhaust velocity, 1 5/8 is the recommended size for a stockish 350.

 

[84_Chevy_K10]

Re: \"Exhausting\" education

Don't forget an H pipe, it makes the rig sound so much better!