What the theoretical top speed for a 4.176 (original is 3.944) final gear ratio manual gear box? I am running on 17 inch also. 205/40/ZR17 compared to original 155/55/R13.

I think my speedometer are off (not accurate) already because of the above 2 modification. But wonder how much off are they. Are they faster than actual speed or slower than actual speed? By how much?

I know mine engine cut off at 6.6K rpm. Any way to remove the power cut? My engine is still pulling strong when the cut came in. My tuner told me I should be able to rev to 7.5K to 8k if I removed the power cut.