Billet intake manifolds for road racing?

As you might be able to tell from the title, I’m curious to see if anyone has any experience running one of these billet aluminum intake manifolds in a road racing application. They’re generally made out of 6061, which has pretty high thermal conductivity. I’ve been kicking around the idea of biting the bullet and picking one up for my car. The shorter runners on the one I’m eyeing will certainly help with top end power delivery, but has anyone on here done this on a car that sees high loads for extended periods of time? The car is a C6 Z06 used for street, HPDEs, and hopefully some open road race competition later this year. It is currently setup on the ubiquitous MSD manifold. It’s plastic, which is great at not soaking up heat, or imparting it onto the charge air, but the runners are a mile long so it kills the top end. My main concern is that the billet manifold won’t be seeing nearly the external air-flow that something like a front mount intercooler would see, so it might be prone to heating soaking and causing IATs to increase after some time.

any insight is greatly appreciated. Thanks!

-Kenny

Phenolic spacers/gaskets may help. The higher the engine speed the less proportional effect heat transfer from the head and manifold has in charge temperature. Sounds like VE gain at operating rpm will far outweigh any thermal effects.

There are also thermal barrier coatings you can use to reduce and heat transfer from external sources.

What you need to do is give some serious thought on what the potential heat sources are, and what relevance they will have. For example, the charge temperature entering the manifold, radiant heat sources that may fall on the manifold, the under-bonnet temperatures where the maifold is, and the heat transgfer from the head - with some the temperature may be lower than expected, and may actually reduce the temperature of the intake.

Thanks for the replies. That’s mostly why I’ve been curious about people with experience in this niche in the market. I know under-hood/bonnet temps are above ambient. The hood/bonnet is vented though; to help evacuate some of that hot hair. The car is also running E85, which should help with the temps where the manifold contacts the heads. My hope is, the air velocity and volume at high loads will help pull heat away from the manifold. I know the car, under this heads/cam setup, can benefit by about 75hp over the current manifold (per recent independent dyno tests), as the plenum volume and runner length will better match the valve train setup. I suppose I’ll give it a try, and see how the car does at the next road race event.

thanks again!