TheeZ

Hey ive got a R180 diff in my 79 now and im planning on swapping in a R200. What isn't on my car now that i am going to need to fit in the R200. Ive got a later 280zx tranny an now im raising the rear end ratio to help match the gearing. Thanks !

-TheeZ-

icice9

what you have a 79 with a r180??? im not too sure but i think all zxs had the r200 in them already.... you might wanna look into that

Bleach

1979 might have an R180

http://www.zhome.com/ZCMnL/tech/GearRatios.html

If you have a 3.36 or 3.54 rear end, I don' t know how or why you would raise the gear ratio. Do you mean a higher number? (lower gearing) like 3.9?

TheeZ

Sorry about being somewhat unclear. I'm pretty sure ive got a r180 in my z. I'm also pretty sure that the 280zx's came with either the r180 or r200 depending on the trim. I don't know what trim i have as the dash board was replaced including that little vehicle description # plate. I picked up a later z transmission which is meant to be paired with a higher ratio differential in the n/a version (ie 3.90). If my z has a r180 diff (which im pretty sure it does) then i believe i have a 3.36 or a 3.54 differential. 3.36 or 3.54 would be somewhat slugish off the line with the later trany wouldn't it? By higher ratio i mean higher number 39:10 -3.90. I had a 3.70 r180 diff layin around and it looks just like the one i have in my car. I also have a r200 (bigger and bulkier than what i have in my car) 4.11. Thats why im pretty sure ive got the r180. Also the hayes manual specifies which diff. (r180 or r200) goes with each z trim model. I just don't know which trim i have. Hope that clears things up...Thanks for any help!

Oh and btw im swaping in the 4.11 from a '85 200sx turbo (I cracked it open to be sure it's a 4.11)wahoo