ruger988

Does anyone here know if a 323 GTX rear-diff will go in an NA miata? i have the opportunity to buy one from a teacher of mine that needs a little work for $350 if i do that i can throw the diff from that in the miata until i get enough cash for the 1.8 setup, then put the 323 back together and get to work on building that.

akaryrye

iTrader: (5)

ruger, i thought you had the vlsd? Anyways, For 350, it better be a 7" Open differential at least. If you wanna throw that thing in your 1.6, you are throwing your money away.

ruger988

I am most likely getting the 1.6 VLSD to use temporarily, but since im getting ready to buy an entire 89 323 GTX for 350 i figure if the rear end fits, i can throw it in for a few months while im fixing the 323 to mkae it reliable as a daily. the entire 323 GTX is 350 not just the rear-end!!!

akaryrye

iTrader: (5)

Ah, ok I see. This might be something you need to check out for yourself. Assuming its the AWD version, I would guess it has the equivalant of the 1.6 differential, but i dunno for sure. Its very unlikely you will be able to find out without just trying either.

ruger988

yea, it's the AWD one, i was just hoping that someone here knew one way or the other because i have two options:

1. buy the 1.6 VLSD from turbo tim for around 140 -150 shipped and use that for a few months until i can get a 1.8 setup and pass on the 323 GTX that i want BAD!!

2. buy the 323 GTX (if the dif fwill fit) for 350 and put that dif fin the miata while i'm saving for a 1.8 setup. once i get the 1.8 i'll throw the dif fback in the 323 and start working on making her reliable.

so if anyone KNOWS for sure that the 323 GTX rear diff (the AWD turbo 1.6L 323 from 89) will bolt in place of the stock 1.6 differential PLEASE let me know ASAP so i can go ahead and jump on the 323 before someone else does.

Thanks, Brian

Braineack

iTrader: (62)

im pretty sure they are the same.

ruger988

i have access to the 323 GTX at school (with several lifts) but not to my miata right now, i would be taking the diff off of the 323 driving 200 mile sto my miata and attempting the install, anything i can look for on the 323 diff that would tell me for sure one way or another?

Braineack

iTrader: (62)

measureing it.

but Randy does state it on his website, so I would be inclinded to believe him:

http://members.aol.com/solomiata/Drivetrain.html

ruger988

I sent him an e-mail trying to figure out what all i will need (whether the housing slips right in or if i'll need the axle's etc... like i will for the 1.8) so i will post back when i hear from him, but if anyone else has any input i'm all ears right now!!

thanks braineack

Braineack

iTrader: (62)

I'm banking on the exact same diff, i wonder if you can't call mazda and see if the part numbers are the same for the carrier and pinon housing.

ruger988

that might work.....you know if a dealership could tell me, or would i have to try to get in touch with mazda directly?

Braineack

iTrader: (62)

im sure the parts department could help.

ruger988

all the mazda dealership here in chesapeake, VA would tell me is that they were different....not sure what he looked up as far as open/VLSD for the miata and not sure what's on the 323, so i guess i'll just wait from a reply from the solomiata guy and go from there.

thanks again braineack

akaryrye

iTrader: (5)

Ok im in the process of rigging up the RX7 LSD and noticed that the 4.1 to 1 gearing has 10 pinion teeth and 41 ring teeth. The 3.909 has 11 pinion teeth and 43 ring teeth. Now what would happen if i mixed and matched? The calculator tells me that with the 11 pinion/41 ring I would get 3.73 gearing and with 10 pinion/43 ring I get 4.3 gearing.

I dont see how mixing would be a problem? I sort of want to try 4.3 now since the pinion nut is not coming off and this way i wouldnt have to mess with backlash and stuff this time around. Then down the line I can change the gears to what I want.

magnamx-5

iTrader: (7)

so long as you use the same pinion and ring gear no problem i couldnt get the engagment right when i tried the rx7 ring gear, so mix and match would be a no go.

Braineack

iTrader: (62)

i assumed you could mix and match....but maybe not. I'd stick with the 4.10 and call it a day.

akaryrye

iTrader: (5)

ya i was trying to put it together right now but it seems like magna is correct. 4.1 is probably the right ratio for a miata anyways. its not like it would make that big of a difference anyways.

turbopezz

3.73 gears would be real nice with 300 hp.i like the idea of the 3.7 even for my car and im only shooting for 240hp.

i was reading the record holding bp in a street miata ran 10.9.he was using 3.73. so he could reduce it to 3 shifts in the quarter mile.but he had 400hp i believe.also i think his ''screen name'' was skyler or styler.i read it on some subie forums a while back.

turbopezz

also akaryrye are you using 4.10 or the 3.9.i might be interested in the 3.9

bripab007

Yes, it was Skyler, it was more like 500+rwhp (hence the 139+mph trap-speed), and he had a Ford rear-end and a Turbo II tranny, hence the unique final drive ratio.