RX7 fd3s transmission in my MX5
03-26-2007, 02:30 PM
#1
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RX7 fd3s transmission in my MX5
The miata transmission is very nice, but can't handle safely more than 250 WHP.
At stock situations or at light turbo setups you 'll not deal with problems, but with 300+ WHP the 2th or 3th gear sometimes will gone
So there are two solutions
1)exotic stuff gears (os giken, quaife etc) but very expensive
2)adaptate transmission from another car, more inexpensive from the first solution but very difficult to do a perfect job.
So I put a turbo trans model "R" from RX7 fd3s (93-95).
It was from the beginning a difficult modification but the engineer succeed in this 100%.
The gear lever is exactly in the same position like the stock, and the "sense" of changing gears maybe is better than a stock transmission miata.
The 1-2-3d gears are a little shorter than stock gear ratio
The 4th is the same 1:1 ratio
And the 5th is much longer than stock ratio!! And this is very nice for a 340+ hp turbo miata!.
The modification based to a new housing between the block and the RX7 transmission. We modificated the miata housing (bellhousing? ) and connect to its end, the end of the RX7 housing.It was a very difficult job because it had to be perfect at straight line with the stock one.
You will see at the fotos what exactly we have do because my english are not so good to explain exactly what I want to tell.
The driveshaft was cut and modificated to match to the RX7 transmission.
At stock situations or at light turbo setups you 'll not deal with problems, but with 300+ WHP the 2th or 3th gear sometimes will gone
So there are two solutions
1)exotic stuff gears (os giken, quaife etc) but very expensive
2)adaptate transmission from another car, more inexpensive from the first solution but very difficult to do a perfect job.
So I put a turbo trans model "R" from RX7 fd3s (93-95).
It was from the beginning a difficult modification but the engineer succeed in this 100%.
The gear lever is exactly in the same position like the stock, and the "sense" of changing gears maybe is better than a stock transmission miata.
The 1-2-3d gears are a little shorter than stock gear ratio
The 4th is the same 1:1 ratio
And the 5th is much longer than stock ratio!! And this is very nice for a 340+ hp turbo miata!.
The modification based to a new housing between the block and the RX7 transmission. We modificated the miata housing (bellhousing? ) and connect to its end, the end of the RX7 housing.It was a very difficult job because it had to be perfect at straight line with the stock one.
You will see at the fotos what exactly we have do because my english are not so good to explain exactly what I want to tell.
The driveshaft was cut and modificated to match to the RX7 transmission.
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03-26-2007, 03:05 PM
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Of course is very very cheapper than buying the gears!
It's the best value for money solution.
The pictures are from the mobile phone, and I think I have not pictures of the process.
It's the best value for money solution.
The pictures are from the mobile phone, and I think I have not pictures of the process.
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03-28-2007, 05:39 AM
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Is there much difference between FD and FC transmissions? I have 3 Turbo II transmissions that I was thinking of using. And with the Price of torsens I as thinking about doing the 8.8 swap to get a bullet proof driveline.
Also wouldn't you have to get a custom clutch disc? Being that the input shaft splines are different?
Also wouldn't you have to get a custom clutch disc? Being that the input shaft splines are different?
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03-28-2007, 09:33 AM
#12
No. The big difference is that the FD is setup for a ppf on the exhaust side. Nobody uses them for the swap because they cost more and it's the same center section as the FC tII. The FD rear has no "wings" for mounting, where the FC does. You need to resolve the hub/half shaft connection since the FD/FC shafts are larger. Going to the big rear though, only requires shortening the drive (propellor) shaft. Whereas keep the Miata rear would mean combining a Miata and FD/FC shaft. You will need a spline specific disk, but any clutch builder can do this since it's just swapping out the center hub.
Here's a good link on the subjects:
http://www.geocities.com/Crash41301/
Here's some excellent photos from the "miataroadster" guy- my guess is he'd make/sell you the plate:
http://billwilner.myphotoalbum.com/v...album07&page=1
- rob
Here's a good link on the subjects:
http://www.geocities.com/Crash41301/
Here's some excellent photos from the "miataroadster" guy- my guess is he'd make/sell you the plate:
http://billwilner.myphotoalbum.com/v...album07&page=1
- rob
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03-28-2007, 03:11 PM
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No. The big difference is that the FD is setup for a ppf on the exhaust side. Nobody uses them for the swap because they cost more and it's the same center section as the FC tII. The FD rear has no "wings" for mounting, where the FC does. You need to resolve the hub/half shaft connection since the FD/FC shafts are larger. Going to the big rear though, only requires shortening the drive (propellor) shaft. Whereas keep the Miata rear would mean combining a Miata and FD/FC shaft. You will need a spline specific disk, but any clutch builder can do this since it's just swapping out the center hub.
Here's a good link on the subjects:
http://www.geocities.com/Crash41301/
Here's some excellent photos from the "miataroadster" guy- my guess is he'd make/sell you the plate:
http://billwilner.myphotoalbum.com/v...album07&page=1
- rob
Here's a good link on the subjects:
http://www.geocities.com/Crash41301/
Here's some excellent photos from the "miataroadster" guy- my guess is he'd make/sell you the plate:
http://billwilner.myphotoalbum.com/v...album07&page=1
- rob
The reasons are:
1)The lever goes 10 cm back from the stock position
2)You have to cut chassis and modify many thinks to the car such as dowpipe etc, because the slave cylinder is from the other side.
3)It' more difficult to do, more difficult to succes the distances at the adapter plate etc
4)FD 93-95 trannie is better than an FC trannie because it's the latest version of "R" series mazda transmissions.
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03-28-2007, 05:52 PM
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I am versed.....lol.... but I was just wondering why he was using a FD tranny when you can get FC trannys for a buck fifty. Plus I have 2. Just wanted to know the hoopla bout the fd tranny
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