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Sweeny Todd Sweeny Todd is offline
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Join Date: Apr 2006
Location: Houston, Texas
Posts: 221
So I need to ask a question here.

Miata's have a Compression Ratio of 9.5:1. They are routinely turbocharged and intercooled with a minimum net increase in HP of about 60%.

Honda S2000's have an 11:1 CR. They are routinely supercharged to provide a net increase of 35% in HP.

This is done with no internal engine modifications.

Now, there are two differences. First, the head designs on both the Honda and the Miata are far more advanced than our antique p-cars and second, the computer engine management is much more advanced as well. As they ought to be given 20 some odd additional years of progress.

So here's my question. Even with the above limitations in head design and engine management: why would we ever have to decrease the compression ratio just to turbocharge the motor. Seems to me that if I turbocharge my 3.2 Carrerra motor, I should expect to be able to get at least 60% more HP like on a Miata. The compression ratio on my 911 is waaaayyyy lower than the Miata.

That would be, lessee 241*1.6=385hp? Yeah. That'd do me.

Let's be less aggressive and use the Honda numbers, 241*1.33=321hp. That'd work just fine also.

Am I missing something?

Old 11-22-2007, 08:09 AM
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