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arrowheadracing
01-11-2005, 11:31
Anybody experiement with a larger crossover pipe ? I am going to build a mandrell bent one and thought about making it 1/4 to 1/2 bigger, maybe make the flange inlet stock size and upgrade it right from there about 1 " down or so. I ll ceramic coat it and thought about wrapping it with heat wrap. I am not sure if the larger size would slow the flow down too much , maybe wrapping it will help keep it warm and flowing the same speed , but in greater volume ?

Any ideas on that one ?

Thanks
Todd

Spindrift
01-11-2005, 13:23
AH,

I think any enlargement of the crossover would be counter productive. Eventually, you're going to have to come back down in diameter, and that will always be your limiting factor. It's a turbulence thing. I think it's a good idea to wrap your crossover, and exhaust manifold, and turbo, if only to minimize under hood temps. I don't believe anyone has demonstrated that wrapping the crossover has provided measureable performance gains. Someone please correct me if I'm wrong.

arrowheadracing
01-11-2005, 15:19
Yeah I am not sure what size the cross over is , and if there is really any way to enlarge it ( even an 1/8 or so). But I think with mandrell bends and wrapped that would definetly speed up exhaust gases. Since the hotter the gas the faster it flows. Many reasons why you ll notice that exhaust systems are designed with smaller tail pipes then the rest of the system, to keep the exhaust gases moving at a faster speed as they cool off farther down the system. Which might be another mute point, how much cooling does it really have at that short of a section if there is any cooling at all.

Todd

DA BIG ONE
01-12-2005, 03:30
Get Flowmasters x-over then ceramic coat if you have the funds.

As for header wrap, I wrap in layers starting with a high heat silicone base, wrap, soak w/ more silicone, wrap again, soak w/ silicone, then SS ties to finish job.

I used the above method to protect my new oil bypass system hoses. While the hoses are good quality, they do get close to the downpipe so heat sleves are a good addition too.