R&C_rallySS

This sounds like a newboe question. Oh yea, I am a newbie. Can you have a after market or GMPP header and a manifold?

FDNY101202

same thing but a mainfold is shorter.

hatrickstu

iTrader: (1)

yes they are the same thing, and no a header is not def. going to be longer than the manifold, they make different types, hence the longtube and shorty headers...

Blown 4-banger

A manifold is usually cast iron, and is on production vehicles, a header is usually a flange with tubes welded to it and flows far better than a cast iron manifold.

rally

The GMPP item is just an SS/SC Manifold that has been "cleaned up" and has less restrictions.

hatrickstu

iTrader: (1)

true but cast iron will last much much longer

Blown 4-banger

WHO CARES!!! You can go way faster for a shorter amount of time!

R&C_rallySS

Thanks alot for the help. I was not 100% sure but you answered my question. Next question...will we get better gains from a GMPP manifold, or polish,port, and hone the stock manifold? Or would short/long tube headers be a better choice for gains?

Allshot

Long tube header is the best option with no cat. Or you can get a shorty header and it should still yield better gains then a gmpp header.

Blown 4-banger

That basically IS the gmpp manifold. I have a mid-tube header with no cat, pretty much can't get more free flowing than that, maybe a long tube header with no cat but it won't be much better than my setup.

hatrickstu

iTrader: (1)

id still like to see defenitive proof of the different manifold/header options power gains; i dont mean 20 different people claiming they gained X amount of horsepower after they installed it and dynoed in completely different weather. id like to see, although it is not likely, a person dyno stock, and dyno with each one on the same day as the stock run, that is the only real way to know true gains.

also, just to clear up some common misconceptions

1. bigger piping does not always mean better flow
2. more flow does not always mean more horsepower

Blown 4-banger

Yes in some rare cases, that is true. For the most part the more exhaust gasses you can evacuate, the better. Now yes I would prolly loose quite a bit of power if I went to 4" exhaust, where a turbo car would gain power.

hatrickstu

iTrader: (1)

take NHRA pro stock cars for example, they run full exhaust piping (obviously no mufflers or cats) and if this were true then they would just run as big of piping as possible, well they dont, they have a series of neckdowns and different diamter piping on all the cars, i believe they actually even have 1 or 2 2.5 inch sections of piping. there is plenty of proof that bigger is not always better, but i do agree with you for the most part on turbo cars. alot of aftermarket systems for honda cars actually hurt the cars because hondas are so well engineered from the factory