Diff ratio?

Engines, Transmissions & Final Drive questions and answers

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speed
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Location: Lugarno, Sydney

Re: Diff ratio?

Postby speed » Mon Feb 16, 2015 8:27 am

PeterB, how much power was Fanta putting out and did the 1.6 diff (with aftermarket centre) die before you sold the car or was still running fine?


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NA6 turbo - 140kw atw - not the most powerful but so much fun :D

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PeterB
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Re: Diff ratio?

Postby PeterB » Mon Feb 16, 2015 3:50 pm

Speed

I initially ran the 4.3:1 NA6 diff with Mazdaspeed centre with a NA6 turbo with 135rwk for a year or so of road use and track days, but no hillclimbs, so no competition full power launches.

The Mazdaspeed lsd centre was purchased from Mania (I think) and fitted by Reliance Automotive in Canberra into a 100,000 km old NA6 diff.

I then swapped the motor and drive-line to Fanta, still with turbo, and ran a season or so of sprints and hillclmbs (with full power launches on slicks), then fitted the 1600 normally aspirated motor with about 95rwk and ran another few seasons of sprints (1.09 at Wakefield Park) and hillclimbs (48.0 at Fairbairn Park hillclimb), running slicks or semi-slicks.

The diff was serviced once by Reliance about a year before I sold Fanta and it needed one plate replaced to set-up correctly. Reliance couldn't get any spares for the lsd and had the plate made. The lsd was operating fine when I sold Fanta.

However the guy who bought the original road 1600 with stock 1600 blew up 2 or 3 diffs on the street, so it seems to be how you use them that makes a big difference, or else I was just lucky.
Peter B
MX5 free for present

speed
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Re: Diff ratio?

Postby speed » Mon Feb 16, 2015 6:00 pm

Thanks Peter. I bought a new KAAZ LSD centre from Zossy and plan on fitting in my not yet complete supercharged NA6.

Money is a bit tight so I was considering on selling.
Seems as though it is in my best interest to keep it and find money elsewhere.

I've never killed a diff in my life and like to think that I drive sympathetically with the car in mind.

Really appreciate your feedback, so thank you!

Jeo, my offer no longer stands but I do wish you the best of luck.


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Jeo
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Re: Diff ratio?

Postby Jeo » Wed Jun 24, 2015 6:56 pm

So long time dead thread but for those playing at home in the future, a Mazdaspeed clutch pack centre came up cheap locally, so I went with that. Retained the smaller 1600 6" diff and kept the 4.3 ratio as well.

Is significantly nicer on the street but doesn't appear to like the tighter motorkhana stuff.


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