Custom H pipe question, need experienced advice

[85_SS_302_Coupe]

My buddy has an S10 that currently has straight pipes on it and we're looking to make a crossover pipe for it (basically an H pipe). What i'm curious about is, does it matter how long that crossover pipe is? On most Mustang H pipes you see, the pipes come together and the " - " in the middle is only 6 inches long or so....with his, the pipes come straight off the headers so that crossover will be at least as wide as the headers are, which i figure is at least a foot and a half wide. We're trying to be as cheap cost wise as possible so we're trying to avoid getting into mandrel bends and making it all by scratch..we just wanna weld in a crossover and go but we're unsure if it'll be ok being that long.

 

[bynummustang]

Sounds about right. Can you just get the dimensions from a BBK site or something? I don't know if it being a certain distance from the headers makes a difference.

 

[85_SS_302_Coupe]

I just wanna cut and weld a straight cross over between what he has now...nice and easy. I just wonder if the length of the crossover makes a difference.

 

[phutch11]

Supposedly the length of the H-pipe is not terribly important, what is important is the distance of the H pipe from the engine. "Experts" say to take a crayon and make a mark from where the exhaust bolts to the headers down the exhaust pipe towards the mufflers and then run the car.

Where the crayon mark stops melting is where you should weld in the crossover.

Good luck

 

[85_SS_302_Coupe]

Supposedly the length of the H-pipe is not terribly important, what is important is the distance of the H pipe from the engine. "Experts" say to take a crayon and make a mark from where the exhaust bolts to the headers down the exhaust pipe towards the mufflers and then run the car.

Where the crayon mark stops melting is where you should weld in the crossover.

Good luck

Yeah i've heard of doing this trick, but with grease instead of crayon, and for making collectors off the end of headers but i can see where it would make the same sense with the crossover.

 

[cenok is family]

length shouldn't matter. if you look at most H pipes for 60's GM's, the cross over is over a foot long

 

[NIKwoaC]

You want it as short as possible, for the same concept that makes X pipes work so well. You want the exhaust pulse to travel as short as possible a distance to relieve the pressure differences. Of course, any crossover is better than none.