01-11-2013, 09:53 PM
Join Date: Sep 2012
Total Cats: -1
RX-7 trans for better cruising?
Found this on another site, and it got me thinking about an RX tranny swap. Seems that 1-3 are nearly the same but 4 and 5 are much taller. Have a peek.
I wish I knew- the parts interchangeability page went away a few years ago.
According to the spread sheet I made for this work- my '99 has a 4.30 rear, 3.136 1st, 1.888 second, 1.33 third, 1 4th, and 0.814 5th.
and I chose gears that are supposed to go into that box and FD that went into the rear- but I'm not sure.
But in choosing a 86-91 RX-7 5 speed (3.415, 2.002, 1.366, 1 and 0.691) and a 3.91 rear end (can't recall where that came out of) I got a comparison, gear, Stock, modified- in rear wheel ratio:
1st- 13.48, 13.59
2nd- 8.12, 7.83
3rd- 5.72, 5.34
4th- 4.3, 3.91
5th- 3.5, 2.7
So 1-3 are pretty close, and 5th would lower a 4000rpm cruise to 3087 rpm. Gotta think that would do wonders for fuel economy.
I had been thinking of a turbo 1.6l. But could not figure on how to make the calibration production quality and reliability vs. my '99. so...
Is this really possible? If so I'm going to find an RX as soon as Pick-and-Pull opens.