Rear diff

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

Rear diff

Postby braindead90 » Tue Oct 12, 2021 7:55 am

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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Re: Rear diff

Postby NukeKS14 » Fri Oct 15, 2021 8:57 pm

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.)

Image

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: 11
Joined: Tue Oct 12, 2021 2:45 am
Car: Nissan 200SX CA18DET RHD

Re: Rear diff

Postby braindead90 » Tue Oct 19, 2021 8:43 pm

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: 11
Joined: Tue Oct 12, 2021 2:45 am
Car: Nissan 200SX CA18DET RHD

Re: Rear diff

Postby braindead90 » Tue Nov 16, 2021 10:32 pm

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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Re: Rear diff

Postby PapaSmurf2k3 » Tue Dec 21, 2021 11:34 am

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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Re: Rear diff

Postby float_6969 » Wed Dec 22, 2021 9:06 am

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: 11
Joined: Tue Oct 12, 2021 2:45 am
Car: Nissan 200SX CA18DET RHD

Re: Rear diff

Postby braindead90 » Mon Mar 07, 2022 2:43 am

thanks for your help. really appreciate it


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