Thread: H-pipe help

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I have duels on my 73 nova with a 350, seperate pipes. Is the h-pipe install worth the effort/expense? what r the benifits, draw backs?

Advantages: Better low end, better scavanging.

Disadvantages: You have to install it.

I put one on every street car I build.

http://www.carcraft.com/howto/95838/index3.html

Did you get the choice of weapons in any of those duels?

Sorry . . . couldn't resist . . .

I'll second that, have done it for years and will continue to

Advantages: Better low end, better scavanging.

How can you tell the best place to put a crossover? Is there an optimum position in the system for maximum effect?

Thanks, Bud

As close to the collectors as possible, or with out headers as far forward as possible

Thanks. I'm just getting ready to bend pipes for a new system - might as well do the crossover while I'm under there.

Thanks, Bud

Originally posted by budzilla
How can you tell the best place to put a crossover? Is there an optimum position in the system for maximum effect?

Thanks, Bud

There is a proper place to put that crossover. Its been a while since I've done it but I will find out for sure. If my memory serves me correctly ,You paint the collector and when the pipes heat up the paint will burn off.The crossover goes 6 inches behind the burnt paint. A friend who was national champion in both late model sportsman and bush grand national taught me this.He said it was good for 15 to 20 horsepower on a race motor if done properly.If thats true thats about the cheapest way I know off to gain good power.

Originally posted by DennyW
See if you can find out at what rpm's ? I mean, low rpm's, mid, or high, where the paint burns off. Also, does this go with the low, mid, or top end power ?

Denny, Very good question.Wish I new the answers but not sure I do. I may not be able to find out until the first of the week. I think we held mine at 2200rpm for a couple minutes after it had already warmed up good.I would think it would give increased power through out the whole RPM range. I will try to get better info ASAP.

It was explained to me once that the crossover produced a scavenging effect - flow through one side of the system caused a draw that helped extract from the other side and so forth. Makes sense. Even with big pipes, it seems to help, so I'm inclined to believe the scavenging explanation above just reducing backpressure. In a way, it's like the equal-length tubing used on headers - it helps tune the system.

I've added the crossover to a car that didn't have one, and it wound up quicker and seemed to breathe easier.

I like the paint idea. I assume you use regular (non-hi-temp) paint. My guess would be to run the RPMs where you want the power, or just drive it the way you plan to and see where the paint burns off.

Thanks for the good tips.