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Diff ratio upgrade

Old 10-20-2008, 04:21 AM
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Diff ratio upgrade

I have access to a 6MT diff to swap into my 4AT 03-model.

I'm betting the housing is the same but I know Mazda well enough to know they like to screw you over by making little changes on parts.

So the question is, do we know if the diff is a straight swap or is the flange different for example.

The idea is to use the 4.33 rear to assist in the sluggish take off & throttle response.

REgards
Old 10-20-2008, 03:37 PM
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let me know that out come of this. i might do the same thing
Old 10-20-2008, 05:38 PM
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ive been wondering about this myself. im geting close to being done with the sr swap and i have been tossing around the idea of getting a gear set from a A/t so i dont loose any top end considering im using a 5 speed now...do the a/t have a lsd as well.. and as for the d/s flange i can measure mine tomorrow and post up the dimensions to compare is some one wants to measure there a/t diff
Old 10-21-2008, 06:38 AM
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Originally Posted by cmr333
ive been wondering about this myself. im geting close to being done with the sr swap and i have been tossing around the idea of getting a gear set from a A/t so i dont loose any top end considering im using a 5 speed now...do the a/t have a lsd as well.. and as for the d/s flange i can measure mine tomorrow and post up the dimensions to compare is some one wants to measure there a/t diff
Its so common to see a rotary engine installed into a Nissan, Toyota, Mitsubishi or another Mazda etc but very rare to find a Piston conversion on a rotary Mazda. Hope your prepared for all the "Sacreligious" comments.........

In regards to te LSD issue. It depends on the export market the RX-8 is sent to.

Example. Aussie 4AT versions get sports suspension, big brakes & LSD just like the manual. So the advise is to check around first.

REgards
Old 10-21-2008, 12:04 PM
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Yeah, if you've got the LSD, you already have the same rear gear as the MT.

As far as the manual vs automatic differential, Paul at Mazmart should know if they are the same or different. They built a diff for my 4AT with the 4.77 gear in it.
Old 10-21-2008, 12:05 PM
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Originally Posted by cmr333
ive been wondering about this myself. im geting close to being done with the sr swap and i have been tossing around the idea of getting a gear set from a A/t so i dont loose any top end considering im using a 5 speed now...do the a/t have a lsd as well.. and as for the d/s flange i can measure mine tomorrow and post up the dimensions to compare is some one wants to measure there a/t diff
My understanding is that if you have an AT with an LSD, you have the same rear gear as the MTs. If you have the base AT it is a taller rear gear, but it does not have the LSD. I'm sure Mazmart could build you a custom rear diff with the LSD and a taller rear gear. They built mine for me with the 4.77.
Old 10-21-2008, 12:08 PM
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ive got a few MT differentials if anyone is up to swapping... im pretty sure AT has lsd too, just base model is different. IE, you have DSC, you have the same LSD whether its auto or manual whatever...

Also pretty sure they swap right out, but never done it myself. Had a few people interested in the upgrade from base, but never had any complete it.
Old 10-21-2008, 01:44 PM
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I should have a couple more ring and pinion units in stock from the 09 cars before too long. They are 4.777.

Paul.
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