Project 200whp N/A
#221
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I believe Emilio might be alluding to the fact that the Rotrex's large compressor wheel, much like a large turbo with a large compressor wheel, generally creates less heat at similar flow rates than a smaller one. And most turbos used on Miatas have smaller compressor wheels than that found on the Rotrex.
But I don't want to put words in Emilios mouth. That's my impression.
But I don't want to put words in Emilios mouth. That's my impression.
#225
The difference is the raw outlet temps and how much intercooling is required to get to that IAT and where in the RPM range that peak compressor efficiency is.
Looking at the point where cylinder pressure should be the highest, a 300whp turbo might be 4800rpm. The 300whp turbo system will be generating a bunch more torque at 4800 and commensurately higher cylinder pressures (det potential).
The natural VE peak of a stock BP is usually around 6200rpm, where the Rotrex is basically at peak torque when geared for a 7000rpm redline. The VE peak falls off enough after that to reduce torque even though the blower is making more boost. The difference here is that the equivalent Rotrex is hitting its peak efficiency there so it requires the least intercooling. This is how a Rotrex blower at 13-16psi can match the same size turbo at 18-21psi for peak power. Also why we can run 300whp in a Rotrex with stock ignition timing. It's possible to match efficiency of a Rotrex with a turbo but it requires a compressor with a much greater CFM capacity than is required for target whp with its corresponding lag.
Turbos obviously kick *** on track. They are just more expensive and involved to make reliable than a Rotrex making the same peak power. Unless you have a TSE turbo kit like I do.
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#229
If you are serious about the C30-94 comment, then check out Track Dog Racing's upcoming kit. I went there personally two weeks ago and got a ride in the shop car with 300+ whp. It was incredibly fun and their mounting bracket is way stronger than the Kraftwerks piece. I got to compare them side-by-side.
#233
cxracing.com: CXRacing Performance Header For 89-99 Miata MX-5 NA 1.8L Equal Length Long Tube
So when are you guys dynoing this abomination :v
#236
cxracing.com: CXRacing Performance Header For 89-99 Miata MX-5 NA 1.8L Equal Length Long Tube
So when are you guys dynoing this abomination :v
I bet the RB is gonna be real close to the Mahara and that CXR last by a good margin.