A little help

[shortshift]

Can't decide between Forced Induction or a Cosworth cylinder head. My concerns about super charging/turbo charging are about cylinder pressure. It would seem that excessive cylinder pressure would lead to premature ring-wear/piston-groove wear. Whereas a high-flow cylinder head would give increased horsepower at the expense of fuel comsumption. I don't really know. Just wondering if anyone can provide real-time experience. Shortshift

[p4R4d0x]

For what application? I can't imagine just a high-flow cylinder head giving much gain on its own.. but I'm no expert. I would imagine that would be something meant to be combined with FI, with the higher flow of the heads helping the engine 'keep' up with the air being forced in by the turbo/supercharger.

[black roadster]

For what application? I can't imagine just a high-flow cylinder head giving much gain on its own.. but I'm no expert. I would imagine that would be something meant to be combined with FI, with the higher flow of the heads helping the engine 'keep' up with the air being forced in by the turbo/supercharger.

What he said. Not sure what year model you are referring to but the stock 1.8 from 1994-2005 can handle 200 RWHP all day long.

[cwisenheimer]

^^^+1

Furthermore, you can spend lots of money on IHE mods and never come close to the bump you'll get by going to forced induction. Assuming you have a 2006 or later, the best-sorted FI is the supercharger from FM. There are other options, but the forced induction market for NC's is not as mature as for the NA's and NB's. Your concern about cylinder pressures isn't borne out by general experience in the Miata market. Tuning is a much bigger concern, thus my FM recommendation.

[SirHustlerEsq]

I'd do the head and a tune.

[SirHustlerEsq]

For what application? I can't imagine just a high-flow cylinder head giving much gain on its own.. but I'm no expert. I would imagine that would be something meant to be combined with FI, with the higher flow of the heads helping the engine 'keep' up with the air being forced in by the turbo/supercharger.

There are two very different schools of thought on an NA vs FI head.

[cwisenheimer]

Let us know what year of Miata you're talking about. That makes a big difference in the possibilities and the "right" answers.

[shortshift]

Sorry folks, I should have said it's a 2 liter 2006. My thought on the cylinder head is that the stock model is a non-interference head while an after-market might give more flow and higher compression (I'm not bothered by increasing the frequency of changing out the timing belt). Chevy v-8's respond very well to high-performance cylinder heads. Didn't know if there was anyone who had tried this on the Miata.