Can I Use Two Phenolic Manifold Spacers?

I have a 1/2 manifold spacer on my stock intake now. I am changing to a 93 Cobra intake. My plan is to use a 1 inch spacer. I also have a 4 inch cowl hood to install, and that got my thinking: since I will have plenty of clearance, what if I used TWO spacers? I know this might be a strange idea, but if spacers really do help keep the upper intake cool, and they do lengthen the runners, then maybe the "more is better" theory applies here. Also, it would put the upper intake closer to the air getting pulled out of the hood which should help keep it even cooler. I don't know if it would even be possible to hook up the throttle cable, EGR, and misc. brackets etc. without major fabrication, but if two inches total is two much I could use a 1 inch and a 1/2 or 3/8. What do you guys think?

7991LXnSHO said:

I think the runners are long enough for most applications as is. I remember some folks even shortening them before aftermarket ones were easily available. If you want to keep it cool, strip the upper and lower intakes and have a thermal barrier applied inside and out to both. Avoiding metal to metal contact in between the manifolds is good, but I think the spacers' real benefit is valve cover clearance. Probably making sure your air comes in from outside of the engine bay will be of more benefit than any air flowing over the upper manifold will be. (As in, use the original CAI kit or an aftermarket that puts the filter in the fender.)

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I already have a MAC CAI with fender well filter. I have a thermal barrier product on most of that, who knows how much it helps keep it cool but it is inexpensive so why not.