Originally Posted by cueball1
Don't have one but it looks to me that they use a much heavier gauge stainless than BEGI. Must be strong as hell for a tubular mani to not need support.
"They" = me. I don't know what BEGI uses on their S4 mani, I think I remember Corky saying on m.net that it is the same as an ebay manifold but they add some trick bracing to keep it alive. All ebay stuff I've seen is thin. Of course, the typical cast manifold is thicker than any tubular manifold will be.
Anyways, I use either schedule 10 (.109 wall) or schedule 40 (.145 wall) 1.5" weld elbows, whatever the buyer wants. And I have only built a schedule 10 mani once. And schedule 80 bends are available in mild steel.
BEGI is supposed to be making a S4 mani out of weld elbows and v-bands too, not sure on the thickness.
EDIT: The only manifold I've made that needed support was my first manifold, a long tube bottom mount ram-horn style, kinda sorta like the begi manifold. Long tube manifolds need support...the longer the primary length, the less stiff the manifold is in general. There's a lot of harmonics going on in the typical inline 4cyl, and a not-so-stiff manifold will buzzzzz pretty violently at certain rpms. This goes for the intake manifold as well...
IMHO (biased!) my manifolds are the better than the typical ramhorn because they are have significantly:
*less bends (less bends=less restriction),
*less primary length
*less heat loss (lower surface area),
*stiffer (think turbo hanging off the end of a tuning fork with the long tube runner manifolds)
*lighter (assuming a weld-ell ramhorn, not thin wall ebay chinese stuff)
*and it's also real easy to get to the hardware. I do not know how much of an issue this is with ramhorn manifolds though.
No one to my knowledge has road-course tracked one of my manifolds. There's not many out there...Paul & Artie have the standard/original, I made one BEGI/FM replacement, my TT manifold, and I have Sav's V-band and a A/C P/S version of the standard in my garage awaiting final touches now. There's also that first manifold I did 7 years ago but that's more of a frankenstein thing and shouldn't have worked as well as it did.