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There's been nothing on this for 2 years. It would be great if Carlos made it available.
Gordon
Gordon,
As I stated in the beginning of this thread : The gear set I used came from a 1989 Mazda MPV mini van "Sport" version 5 speed.
At the time that I built this, I tried to find a source for gear sets through regular channels, to no avail.
Short of pulling teeth and personal favors at Mazda North America, along with the fact that there seemed to be no great interest in this setup, .... I pursued it no further.
Now, I don't get the opportunities to visit the forum nearly as much as I used to, so personally I've not been made aware off nor has it been brought to my attention at CLR. that any interest in this conversion persist.
Good gears can be had from a local bone yards, or from a national network of used auto parts retailers now that they are all networked together through the Internet.
I got my gear set from a "Used Auto Parts" house in St. Lewis.
Ray from the V-8 Rx7 club was instrumental in helping me source my gears.
IF you're interested in building up a 3.73 gear for your Fd, I can provide the Hardened Sleeves to make the conversion work.
I did the research on this, built it and use it. ... It is quite simple.
Besides the Gear set you will need to provide all the normal bits like Bearings, Crush Collar ( Mazda calls it a distance Piece ) and Shims just like if you were setting up a fresh new gear like a 4.37 or something lower.
The rest is normal setup, pattern check, back lash adjustment and assembly.
If enough ppl. seriously got together to bring this to Mazda's attention, I guess it could be followed up with further research but it would require a realistic number and commitment to make it worth while for them.
Thanks for the update Carlos. I sent you an e-mail regarding the sleeves.
Thanks,
Rob Labardee
Originally Posted by GT1-20b
Gordon,
As I stated in the beginning of this thread : The gear set I used came from a 1989 Mazda MPV mini van "Sport" version 5 speed.
At the time that I built this, I tried to find a source for gear sets through regular channels, to no avail.
Short of pulling teeth and personal favors at Mazda North America, along with the fact that there seemed to be no great interest in this setup, .... I pursued it no further.
Now, I don't get the opportunities to visit the forum nearly as much as I used to, so personally I've not been made aware off nor has it been brought to my attention at CLR. that any interest in this conversion persist.
Good gears can be had from a local bone yards, or from a national network of used auto parts retailers now that they are all networked together through the Internet.
I got my gear set from a "Used Auto Parts" house in St. Lewis.
Ray from the V-8 Rx7 club was instrumental in helping me source my gears.
IF you're interested in building up a 3.73 gear for your Fd, I can provide the Hardened Sleeves to make the conversion work.
I did the research on this, built it and use it. ... It is quite simple.
Besides the Gear set you will need to provide all the normal bits like Bearings, Crush Collar ( Mazda calls it a distance Piece ) and Shims just like if you were setting up a fresh new gear like a 4.37 or something lower.
The rest is normal setup, pattern check, back lash adjustment and assembly.
If enough ppl. seriously got together to bring this to Mazda's attention, I guess it could be followed up with further research but it would require a realistic number and commitment to make it worth while for them.
- Did some research yesterday and found some interesting information.
The P/n for the 3.73 gear set is still a good #.
Meaning: Checked the national locater and found there were NONE is stock within the North American system. BUT it does exist somewhere in the Global system. ..... So it could be located as a NEW PART.
Some other interesting bits of info : Mazda made and used these gears in some B2000 and Ford Currier models, and some of these small trucks were offered Internationally as Diesels.
So ....... There should be plenty of these gear sets out there w/ low stress usage.
Last, found out there came an even LONGER gear in some of those models that should for all practical purposes fit the Fd carried and Diff Housing.
This was something I suspected for the longest but, confirmed it yesterday.
Well, it least in print. I have located one and in the process of acquiring it.
I will not elaborate further on this as not to get anyone anxious and the possibility exist that it may not materialize or fit.
- Wanklin,
Got U'r e-mail.
I will go ahead and place the order for your sleeves and will get some extra ones to keep around.
I'll contact U in a week or so once I receive then and proceed.
First of all, thanks for the great balancing job, and the scalloping/clearancing job on my rotors.
I have a nice G50/50 Porsche tranny for my 911 project (strongest 5-sp that Porsche ever made), but it's got tallish gears, with a 3.33 r/p ratio (would top out at 263 mph in 5th, at 8500rpm! see attached pic), so I opted for a 2nd tranny G5003 (not as strong, but shorter gears), with a race 4.0 r/p ratio. This is what I believed to fit the power band of a rotary (not particularly a 20B) better, and I wanted a really responsive car. It's very close to the stock FD ratios at the end:
Just found this thread, has anyone posted this on the V8 forum? This would be huge for us V8 Guys. I am sure there would be a lot of interest if that is what it is needed to get it going? I think I will post over there.
any update on this? I would love to have 3.73 gears in my FD! I already have a kazz locker sitting in my garage and the 300m axles.. Just been tryin to source a 3.90 gear, but 3.73 is much better for me!
I was tempted to sell it all and go cobra 8.8 untill i seen this thread searching.. anyone got updates if it truely works and what needs done etc???
Long shot I know, but bumping this to see if anyone is still alive that has or knows where to get the hardened pinion bushing for this mod? Otherwise it's off to the races, heh ....
just updating this for anyone else; after considerable hours looking into this my conclusion is your best bet to finding the elusive 3.727 ratio 8” Mazda R&P gear here in the USA is the Mazda B2600 truck 2WD model
1987-1993 2WD Manual trans
1990-1993 2WD Auto trans (1987-1989 was 3.909, getting near impossible to find this FD ratio now too)
Don’t even waste your time bothering to find one from an MPV, trust me on this. There are plenty of B2600 2WD models out there. You may have to buy the entire rear differential pumpkin, but it unbolts from the front of the B2600 solid rear axle housing. The guy I bought mine from went ahead and pulled the R&P, which saved me money not having to ship the entire assembly.
but as detailed in this thread, these early year gears are going to require the pinion sleeve mod as described.
.
Don’t even waste your time bothering to find one from an MPV, trust me on this.
That is probably true, my sheet shows that its a 2wd MANUAL transmission MPV, which was exceedingly rare even when they were new. they only occurred from 1989-1992
the other option, just as futile as the MPV is an 88-98 929 MANUAL trans, its also a 3.7, different part number. i've seen one of these in my life. i've seen 12 1960's Ferrari GTO's parked in a row before.
I found a part # for the 3.583 R&P (P03227110B) unfortunately I'm not having much luck finding a wrecked HC Luce with this R&P.
Awesome, thanks for that. I did a lot of looking for it and always came up empty. One of the issues is that the parts listing for R&Ps I could find often don’t list the ratio. However it is only on the 5-spd manual cars and was never on the USDM models. The 5-spd USDM cars initially came with the 3.727 on 1998 models, not sure for how long in the model year history though.
and also for reminding me to get off my duff and get the R&P markings data and photos together
I did sort of conclude that while a lot of these old R&Ps show up in various parts listings, they’re NLA if you try to order one. That said, I may inquire to some potential sources in Japan to try and verify.
.
just updating this for anyone else; after considerable hours looking into this my conclusion is your best bet to finding the elusive 3.727 ratio 8” Mazda R&P gear here in the USA is the Mazda B2600 truck 2WD model
1987-1993 2WD Manual trans
1990-1993 2WD Auto trans (1987-1989 was 3.909, getting near impossible to find this FD ratio now too)
Don’t even waste your time bothering to find one from an MPV, trust me on this. There are plenty of B2600 2WD models out there. You may have to buy the entire rear differential pumpkin, but it unbolts from the front of the B2600 solid rear axle housing. The guy I bought mine from went ahead and pulled the R&P, which saved me money not having to ship the entire assembly.
but as detailed in this thread, these early year gears are going to require the pinion sleeve mod as described.
.
Thank you for this! Any luck on getting the hardened bushing? I saw a facebook post from 2012 of Secondbolt Racing who was going to make a batch.
this has been on the back burner for me over some other things
I just need to get an FD/RX8 pinion out to verify the pinion diameter, try to get to it today or tomorrow. It’s really just a matter of unbolting the pinion nut and knocking it out, the LSD and ring gear are already out. I already have the older pinion assembly in hand. Once I have both then the bushing ID, OD, and length can be confirmed. I see a lot of generic talk on it, but nobody really get’s into the actual details. For a bushing like this thousandths of an inch matter …
however, somebody else reached out to me and said they were able to get in contact with Carlos and supposedly he still has some bushings around somewhere. If somebody can actually supply them reasonably I’m in for 6 or so just to have a few on the shelf, but haven’t heard anything else lately.
I’m not on social media, but if you can get me an email or phone number of a source it’d be appreciated.
this has been on the back burner for me over some other things
I just need to get an FD/RX8 pinion out to verify the pinion diameter, try to get to it today or tomorrow. It’s really just a matter of unbolting the pinion nut and knocking it out, the LSD and ring gear are already out. I already have the older pinion assembly in hand. Once I have both then the bushing ID, OD, and length can be confirmed. I see a lot of generic talk on it, but nobody really get’s into the actual details. For a bushing like this thousandths of an inch matter …
however, somebody else reached out to me and said they were able to get in contact with Carlos and supposedly he still has some bushings around somewhere. If somebody can actually supply them reasonably I’m in for 6 or so just to have a few on the shelf, but haven’t heard anything else lately.
I’m not on social media, but if you can get me an email or phone number of a source it’d be appreciated.
except you’re machining off the outer heat treated material that way but the material itself can play into it as well.
I’d actually be more concerned about what happens when rebuild time comes and the pinion bearing needs to be pressed off. The relationship between how tight the clearances are between bushing-pinion vs the bushing-bearing seems critical to me.
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but the material itself can play into it as well.