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Do any of you know what the F20C's rod/stroke ratio is??

Given the high rpm requirements of the motor, I would imagine it's somewhere around the ideal 1.75. Does anyone know for sure? Thanks in advance!!

ultimate lurker

1.82 (+/-0.01 - measurement error) :-)

UL

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UL-

Somehow I knew it would be you who would answer my query. I can now get a good night's sleep because I know my motor's rod/stroke ratio. Thanks for your help!!

I must say...1.82 is higher than I thought it would be...it makes sense with a 9K redline, but it makes it even more amazing that the torque is as high as it is for a 2 liter.

ultimate lurker

I think it certainly adds one more reason why our low end torque will never be quite as good as the 2.0 liter B-series motors. Between the rod ratio, bore/stroke ratio and valve sizes (not to mention intake port sizes), its clear the F20C was designed to operate primarily in the 5k-6K on up range. compared to the B-series, or even the k20 in teh RSX-S, its definitely hurting a bit on low end torque. We just can't get the port or valve curtain velocity that you need for good turbulence and mixture motion at lower rpm. Might be time for some funky swirl pistons, or at least some more compression.

UL