Difficulty: Gear Ratio change for F25M-R transmission (1999 1.8L Protege ES)

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99 pro ES Silver heavily modified
Folks,

After a long time searching, and calling a few vendors, I can't seem to find any sort of gear ratio upgrade for the F-series transmission (F25M-R) on my 99 Protege. (Not going to swap to a G-series until this transmission blows, as I have a Quaife LSD in there)

I'm looking to make the gears taller with a turbo system rebuild underway, and I'm hoping for at least a final drive ratio increase.

M-Racing doesn't have them, nor does Syncrotech. Any other vendors to give a go with?

Thanks!

EDIT
SOLUTION!

So the Mazda 2 uses the F-series transmission, and I can (and will) get a 3.85 final drive from it ($200 cheaper if you have an SCCA membership and order from mazdamotorsports.com instead of your dealer).
 
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http://www.protegefaq.net/
Look in here, the F25m shows different final drive options, just find which model one suits and start searching.

Thanks for your reply.

I did. I don't see where it lists any gear ratio upgrades or final drive upgrades for the F25M-R. It describes the specs, and it has the Performance Mods section which says nothing other than look at a Nissan SE-R page.

Unless I'm missing something?
 
The 3.619:1 ratio final drive is listed in the second column under BP-ME (MY92-
94 US/Can/ Australia),
Z5-DEL, that will give you more top end.
 
Gotcha, didn't realize that's what you meant. I'm waiting to hear back from Mazda Motorsports USA on the 3.85 (or 3.9 as they call it). The 3.6 might be a little too aggressive to get off the line, but if that's what I can get, then that's what I can get.
 
Sig says 215/40. Go to 215/45 or 225/45 =3
 
yeah, but that comes with more unsprung, rotational mass. Not good for performance.

Solution!

So the Mazda 2 uses the F-series transmission, and I can (and will) get a 3.85 final drive from it (cheaper if you have an SCCA membership and order from mazdamotorsports.com).
 
yeah, but that comes with more unsprung, rotational mass. Not good for performance.

Solution!

So the Mazda 2 uses the F-series transmission, and I can (and will) get a 3.85 final drive from it (cheaper if you have an SCCA membership and order from mazdamotorsports.com).

Good result, what else is revised/different/improved in the mazda 2 trans? could it be worth picking up a mazda 2 trans for components? I rebuilt my 03 protege g-series trans using mazda 3 final drive, both main shafts complete with gears and selectors as well as 1st-4th shift forks/rod. for example, may be similar upgrades available inside the mazda 2 box for you.
 
all the gears are the same except the 4th gear. Mazda 2 is .972, F25M-R is 1.028:1 (per the FAQ).
 
I have a Mazda2.


And a spare transmission. With plans to add a diff and change the final drive possibly. Depends on if I decide to run FSP or jump straight to SMF.


Its too bad I didn't make this plunge sooner, I lived in Dayton, OH up until last June.

I will be back next year for some autocross events though.









If you're interested in getting together some time to tear down transmissions and compare I'd love to do that.

Not to derail but I was considering a Quaife, Mazdaspeed does sell a Cusco diff for the 2, and I bet could fit the Protege F25M-R. I'm torn between the two as the clutch diff should be better for serious auto-x, but I drive 30k per year, and near no maintenance with most of the benefit would be nice with the Quaife.
 
Finally got it all back together after the old turbo dumped it's core on me (oil line was clogged). I went with the Mazda 2 parts from MazdaSpeed, it's a nice change, but not quite enough still droning at freeway speeds, but the turbo compensates! I'm now getting 172hp @ 7psi while I work out the kinks, will up later.

flatlander937 still interested in a meetup?
 
Finally got it all back together after the old turbo dumped it's core on me (oil line was clogged). I went with the Mazda 2 parts from MazdaSpeed, it's a nice change, but not quite enough still droning at freeway speeds, but the turbo compensates! I'm now getting 172hp @ 7psi while I work out the kinks, will up later.

flatlander937 still interested in a meetup?

I have recently found that the 1993 ford laser trans has a 0.731:1 5th gear set compared to the 0.775 of the f-series that came in my 2002 protege.
 
Not to derail but I was considering a Quaife, Mazdaspeed does sell a Cusco diff for the 2, and I bet could fit the Protege F25M-R. I'm torn between the two as the clutch diff should be better for serious auto-x, but I drive 30k per year, and near no maintenance with most of the benefit would be nice with the Quaife.

If you have anymore info about the Mazda2 limited slip, i would love to hear about it. It would be awesome for my rallycross PF/fsp solo car. Was looking into a viscous one but I'm not sold on it
 
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Hi, Im new to the forum and just saw this post. Im a little off topic here but Im interested in getting an LSD for my F series gearbox (I have a 2001 Ford Laser 1.8 here in Oz, same as Protege 1.8). Do you remember the part number for the Quaife?

Was it easy to fit? Did you need any other parts?

Any assistance would be much appreciated.
Cheers
 
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