4.3 gears?
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4.3 gears?
I've noticed, that with all the talk of 4.57 and 4.77 gears, no one mentions the 4.3 (or is it 4.33) rear-drive gearset anymore. Is it not possible to obtain these anymore? I am thinking of a 4.33 rear end in combo with an 04 transmission for my 02 s2k. Should result in something similar to 4.57s in 1st to 4th gears.
...Andrew
...Andrew
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Originally Posted by hecash,Sep 23 2005, 11:36 AM
4.3 are still available, both used and new. Just search on Google for Miata intechangeability for part numbers.
I have just installed an MY04 trans in my MY00 and have a rear assembly sitting on the garage floor freshly built with 4.3 gears. If I get it in before the end of the month, I'll tell you what my reaction is.
You are right, it should be close to a 4.5 or 4.6 net effect.
I have just installed an MY04 trans in my MY00 and have a rear assembly sitting on the garage floor freshly built with 4.3 gears. If I get it in before the end of the month, I'll tell you what my reaction is.
You are right, it should be close to a 4.5 or 4.6 net effect.
Oh, one more thing, and this is nitpicky. Are these 4.30 gears or 4.33 gears that you have in your setup?
...Andrew
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From: SF, California
Originally Posted by hecash,Sep 23 2005, 09:36 AM
You are right, it should be close to a 4.5 or 4.6 net effect.
if you want ~4.56 eq gears you need a 4.44 gear set.
4.44 * 1.20/1.16 = 4.59
4.30 *1.20/1.16 = 4.45
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Originally Posted by hecash,Sep 23 2005, 02:46 PM
I think that you are very close to right for gears 5 & 6 but with the lower gearing for 1 to 4, as it compares to a MY00-03 gearbox, it may be higher.
the difference in final drive is the only difference for 1-4 of MY00-03 and MY04+
final drive
1.16 for MY00-03
1.206 for MY04+
if you want check it out at the gear calculator(what used to be reverands)
http://www.turnzero.com/technical_resource...gear_calculator
4.3 gears with 1.206
Total gearing in first gear:
Maximum speed in first gear: 16.2471114
39.3 mph
2nd gear: Total gearing in second gear:
Maximum speed in second gear: 10.604961
60.2 mph
3rd gear: Total gearing in third gear:
Maximum speed in third gear: 7.6801698
83.1 mph
4th gear: Total gearing in fourth gear:
Maximum speed in fourth gear: 6.0207138
106 mph
4.47 gears with 1.16
Total gearing in first gear:
Maximum speed in first gear: 16.2452316
39.3 mph
Total gearing in second gear:
Maximum speed in second gear: 10.603734
60.2 mph
3rd gear: Total gearing in third gear:
Maximum speed in third gear: 7.6792812
83.1 mph
4th gear: Total gearing in fourth gear:
Maximum speed in fourth gear: 6.0200172
106 mph
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From: SF, California
Originally Posted by hecash,Sep 23 2005, 05:11 PM
I see. So, it's then implied that 5-6 are then taller to keep the highway crusing speeds equal given the shorter secondary gearing. True?
5th gear 6th gear
AP1 .971 .811
AP2 .943 .765
5th gear is 3% taller
6th gear is 6% taller
net including final drive is
5th gear is 1% shorter
6th gear is 2% taller
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From: Ottawa
So... this is a pretty good setup, then...
if you compare an AP1 stock setup (AP1 transmission + 4.1 rear diff) to one with
with an 04 gearbox and 4.3 rear diff, you get:
gears 1 to 4: +11.2% shorter gearing
gear 5 : +5.87% shorter gearing
gear 6: +2.87% shorter gearing
I like this a lot better than just getting a 4.57 rear diff with no change to the transmission, because then you get:
gears 1 to 6: +11.5% shorter gearing
and I like having a relatively relaxed 6th gear. (+2.87% is only around 120 extra rpms at reasonably good highway speeds, like 75-ish mph)
if you compare an AP1 stock setup (AP1 transmission + 4.1 rear diff) to one with
with an 04 gearbox and 4.3 rear diff, you get:
gears 1 to 4: +11.2% shorter gearing
gear 5 : +5.87% shorter gearing
gear 6: +2.87% shorter gearing
I like this a lot better than just getting a 4.57 rear diff with no change to the transmission, because then you get:
gears 1 to 6: +11.5% shorter gearing
and I like having a relatively relaxed 6th gear. (+2.87% is only around 120 extra rpms at reasonably good highway speeds, like 75-ish mph)
