Rear diff

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braindead90
Posts: 9
Joined: Tue Oct 12, 2021 2:45 am
Car: Nissan 200SX CA18DET RHD

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Hey guys. I know that it have been discussed before.
Do anyone knows the length of the ABS vs NON-ABS Driveshaft length?
And is anyone able to tell me if a 3.9 final drive in a CA18DET 200sx is a good choice too?


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NukeKS14
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Car: 1995 240SX SE - KA24DE-T
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2020 Civic Si

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The ABS diff's snout is approx 3/4" inch longer than the non-ABS, so the difference in driveshaft length would be equivalent to account for this (e.g. the ABS driveshaft will be approx 3/4" shorter than it's non-ABS counterpart. they are different length between the S13 and S14, auto and manual transmission as well.)

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Here is a fairly comprehensive list of gearing for most Nissan sports cars;
http://tech.240sxone.com/500/gear-ratio ... rain-info/

and a handy calculator for the RPM/speed/gear ratio. (You'll have to input your wheel/tire info there.)
https://www.blocklayer.com/rpm-gear.aspx

The short answer is it will result in a lower RPM for the same speed/gear that you're currently in. Most configurations have the stock diff at 4.363 for the 180sxs. I think a 3.9X ratio would be a pretty big improvement in terms of drive ability, especially if you've got or are planning to install power adders. If you're completely stock it may feel a bit more sluggish. Lots of info needed to really answer your question but use the tools provided to decide for yourself based on what your goals for the car are.

what-differential-ratio-are-you-guys-ru ... 54478.html

Also that^

braindead90
Posts: 9
Joined: Tue Oct 12, 2021 2:45 am
Car: Nissan 200SX CA18DET RHD

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Thank you so much for your help NukeKS14. just bought the car not long. will go take a look at it and make a decision.

braindead90
Posts: 9
Joined: Tue Oct 12, 2021 2:45 am
Car: Nissan 200SX CA18DET RHD

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anyone can let me know if i am able to swap the internals from ABS diff to a NON ABS diff? do i need to set the backlash again? or just swap the internals and it will be fine?

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PapaSmurf2k3
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Pretty sure you'll have to set backlash again.
Probably a lot easier to just get another drive shaft.

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float_6969
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The internals are identical between the two, but you'll have to set everything up again. That being said, when I swapped from a 4.083 to a 4.36 and installed an S15 Helical differential, All of the stock shims set it exactly right and I didn't end up changing anything. I would NEVER just swap it without changing them though. If it were me, I'd get the diff with the ratio you want, regardless of it being ABS or not, and then get the correct driveshaft to suit. If you swap everything out and it DOES need readjusted it's a HUGE PITA.

braindead90
Posts: 9
Joined: Tue Oct 12, 2021 2:45 am
Car: Nissan 200SX CA18DET RHD

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thanks for your help. really appreciate it


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