experiences with final drive ratio
#1
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experiences with final drive ratio
Ok, so looks like the 7" rear swap needs to happen. The one I have is assembled with a 4.10 r&p. I'm on the stock 4.30 now, and it's very short in 1 & 2, a bit short in 3, fine in 4 and 5 but I wouldn't mind spinning a bit less on the highway.
For you guys who have swapped your rear/r&p, what ratio did you put in, and are you happy with it?
I need to decide if I'm going 4.10 (free and easy) or 3.90 (not free and more work).
For you guys who have swapped your rear/r&p, what ratio did you put in, and are you happy with it?
I need to decide if I'm going 4.10 (free and easy) or 3.90 (not free and more work).
#2
Boost Czar
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I'm loving the 4.10, seems like a good compromise without going too tall. I noticed it right away, 1st is a bit more tame, however I can still light it up. anything taller at my power level would be a waste. Highway cruise is a lot better, right where it needs to be.
#5
Boost Pope
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I went with a 4.10 for the Torsen in my '92. I can still spin the tires (T1S) in first gear, they break loose at around 4,000RPM. This isn't a big change- only 4.6%. I did not change the speedo gear, and according to my GPS receiver my speedo is now less inaccurate than it was before.
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sounds like you guys are happy with the 4.10s. I was afraid that it wasn't enough of a difference to be meaningful. I would like to make 1&2 more useful and also calm the motor down on the interstate.
another thought I had was 410s w/ an rx7 5th gear in the miata tranny. i have the tools and help available to do it, but not the time or motivation.
another thought I had was 410s w/ an rx7 5th gear in the miata tranny. i have the tools and help available to do it, but not the time or motivation.
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Boost Pope
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Like I said, 4.30 to 4.10 is a very small change. You're not really going to notice it unless you're keeping notes. At 70 MPH and assuming a 22.6" tire we're talking about a reduction of 170 RPM (3643 to 3473).
#14
Mark just posted on m.net that the mazdaspeed/comp dropped the price on the 3.63 over $100 (now just over $300) - and somebody said that they bought the set two weeks ago for under $300. So you might just keep an eye on that after driving around with the 4.10. I went for it- especially since the R trans has an even shorter 1st gear than the Miata. I know there's one guy driving around with the 3.63 and the 5speed and he loves it (kmag?). Granted you're gonna lose some time on a standing start acceleration with that setup... but my guess is you'll be shopping a 6 speed soon anyway.
#15
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Mark just posted on m.net that the mazdaspeed/comp dropped the price on the 3.63 over $100 (now just over $300) - and somebody said that they bought the set two weeks ago for under $300. So you might just keep an eye on that after driving around with the 4.10. I went for it- especially since the R trans has an even shorter 1st gear than the Miata. I know there's one guy driving around with the 3.63 and the 5speed and he loves it (kmag?). Granted you're gonna lose some time on a standing start acceleration with that setup... but my guess is you'll be shopping a 6 speed soon anyway.
How much HP is enough to "be fun" with a 3.63 or a 3.90 in a 5-speed?
Sorry to resurrect.