| by wrapping/coating the equal length design. Sure, it takes longer for equal-length runners to reach equilibrium temperature because there is more manifold material, but once at equilibrium there is zero heat loss with "perfect" insulation. Ignoring expense and fitment difficulties, one big problem (I thought) was that stainless steel manifolds will, after enough heat cycles, crack from the weight of the turbos and exhaust hanging on them. I also thought that part of the problem with exhaust wrapping is that the heat stored in the manifolds will continue to cook the turbos much longer after shutdown. For this reason I have never considered wrapping my manifolds -- coating internally seemed the way to go. I'm not saying you have no point; clearly no thermal insulation is "perfect", especially if one is unwilling to use wraps. I'm also glad to see you present an opposing view. But I think there are more important disadvantages than loss of thermal efficiency at work here. Besides that, I'm not sure thermal efficiency outweights the equally-timed pulse advantage, but the other disadvantages might for a street car that isn't rebuilt every season.
- John
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19:08:26 06/19/06
