MX-3.com

I've always wondered this. Would sand blasting and powdercoating/painting the intake manifold affect the flow of air through the manifold or change the natural resonating frequency of the manifold thereby throwing off the VRIS points a little? And for VCs, do you guys powdercoat just the exterior portion or the inside of it as well?
I have a feeling the more technical guys like wytbishop will jump on this one

Well I cant really answer the first one, but usually the only really blast the outside so I would say no.

As for the vc, they blast both sides and powdercoat the top only, they tape off the bottom. At least in my case.

To some infinitesimal degree, yes.

Remember its the whole motor vibrating. The I/M is a fairly rigid structure as well. Its not like shaking different consistency jello, its like shaking a brick versus shaking a painted brick.

The common arguement is that it holds heat in, and warms the air, which we all know is bad...

The resonance doesn't affect the VRIS, that's the air flow path. The resonance system is mostly do to with the sound of the motor. If you've put on a CAI, you've already changed it massively, so I wouldn't worry about it.

Indeed, Ryan is right, it'll ask as an insulator, but many have painted/powdercoated IM's, so it depends on how serious you are towards performance.