Splines? (Axle)
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Splines? (Axle)
How many splines are there one the RX-7 axle shaft where it engages the differential? I'm interested in the larger 84/85 axles. Disc brake if there's a difference.
I was looking at a few things... According to GuruMotorSports, who sells a floating axle kit:
However, according to SoloMiata:
We do have a 7 inch ring gear, right? That'd put us a 26 spline axles. But the GuruMotorSports floating hub kit says it drops in without modification, but it has a 28 spline axle...
Who's right?
*
I was looking at a few things... According to GuruMotorSports, who sells a floating axle kit:
Comes with billet, heat-treated duel splined (28 ford spline axels) with threaded ends for easy axle removal.
However, according to SoloMiata:
7" small axle = 25mm x 24 spline
7" large axle = 27mm x 26 spline
8" = 29mm x 28 spline
7" large axle = 27mm x 26 spline
8" = 29mm x 28 spline
Who's right?
*
Thread Starter
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From: Behind a workbench, repairing FC Electronics.
Nobody? Okay, what counts as a spline? A hill or a valley on the end of the axle.
GuruMotorSports is an Aussie company... They might have some weirdness down there... Like the turbo 12A
or Every RX-7 having the SE bolt pattern... Which I'm not so mad at, cause I have the SE bolt pattern now too. 
GuruMotorSports is an Aussie company... They might have some weirdness down there... Like the turbo 12A
or Every RX-7 having the SE bolt pattern... Which I'm not so mad at, cause I have the SE bolt pattern now too.
Last edited by Pele; Aug 16, 2004 at 12:16 PM.
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Originally Posted by Pele
Okay, what counts as a spline? A hill or a valley on the end of the axle.
I never actually paid attention, I just think "big" and "little" axles...
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Originally Posted by peejay
Well, for every "hill" there will be exactly one "valley" so it doesn't matter which one you're counting.
I never actually paid attention, I just think "big" and "little" axles...
I never actually paid attention, I just think "big" and "little" axles...
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What truck do you have?
If you have a B2000/2200 then you in all liklihood have the 7", and the axle splines are the same as RX-7 for the given year.
If you have a B2600... I think that is the one where some models had the 7.5" rear (it's a 7" with a larger ring gear). Diffs don't interchange but IIRC the complete pumpkin does. Not sure what the 7.5" uses for axles, though.
I *think* some trucks had the 8", maybe that's just the MPV though.
The Sportage FWIW has a Mazda 7" front and Mazda 7.5" rear. This is why you get the FRONT gearset.... right j9fd3s? 
If you have a B2000/2200 then you in all liklihood have the 7", and the axle splines are the same as RX-7 for the given year.
If you have a B2600... I think that is the one where some models had the 7.5" rear (it's a 7" with a larger ring gear). Diffs don't interchange but IIRC the complete pumpkin does. Not sure what the 7.5" uses for axles, though.
I *think* some trucks had the 8", maybe that's just the MPV though.
The Sportage FWIW has a Mazda 7" front and Mazda 7.5" rear. This is why you get the FRONT gearset.... right j9fd3s?
Thread Starter
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From: Behind a workbench, repairing FC Electronics.
Originally Posted by peejay
What truck do you have?
If you have a B2000/2200 then you in all liklihood have the 7", and the axle splines are the same as RX-7 for the given year.
If you have a B2600... I think that is the one where some models had the 7.5" rear (it's a 7" with a larger ring gear). Diffs don't interchange but IIRC the complete pumpkin does. Not sure what the 7.5" uses for axles, though.
I *think* some trucks had the 8", maybe that's just the MPV though.
The Sportage FWIW has a Mazda 7" front and Mazda 7.5" rear. This is why you get the FRONT gearset.... right j9fd3s?
If you have a B2000/2200 then you in all liklihood have the 7", and the axle splines are the same as RX-7 for the given year.
If you have a B2600... I think that is the one where some models had the 7.5" rear (it's a 7" with a larger ring gear). Diffs don't interchange but IIRC the complete pumpkin does. Not sure what the 7.5" uses for axles, though.
I *think* some trucks had the 8", maybe that's just the MPV though.
The Sportage FWIW has a Mazda 7" front and Mazda 7.5" rear. This is why you get the FRONT gearset.... right j9fd3s?
There's a GSL-SE axle and two front struts sitting in the bed.
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Ah.
Well in that case, all GSL-SEs had the big axles, so the Miata stuff should be a "go".
Hmm I seem to recall reading about someone had to custom modify his axles for a Torsen diff because the RX-7 axles didn't engage deep enough. I do believe this was before '99, so it couldn't have been the Miata OEM unit.
Well in that case, all GSL-SEs had the big axles, so the Miata stuff should be a "go".
Hmm I seem to recall reading about someone had to custom modify his axles for a Torsen diff because the RX-7 axles didn't engage deep enough. I do believe this was before '99, so it couldn't have been the Miata OEM unit.
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Thread Starter
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Originally Posted by peejay
Ah.
Well in that case, all GSL-SEs had the big axles, so the Miata stuff should be a "go".
Hmm I seem to recall reading about someone had to custom modify his axles for a Torsen diff because the RX-7 axles didn't engage deep enough. I do believe this was before '99, so it couldn't have been the Miata OEM unit.
Well in that case, all GSL-SEs had the big axles, so the Miata stuff should be a "go".
Hmm I seem to recall reading about someone had to custom modify his axles for a Torsen diff because the RX-7 axles didn't engage deep enough. I do believe this was before '99, so it couldn't have been the Miata OEM unit.
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Originally Posted by Pele
I believe you lose 10mm of spline engagement. Creating longer axles helps... So long as I'm looking at creating longer axles, I might as well look into something of an improvement... Hence the Guru Motorsports floating hub kit... And there I found the discrepancy...
The car in question was David Lane's turbocharged thingus... hell where is David Lane now? Anyway, with the power he had on tap, he was concerned with spline engagement. Other people reported no problems, so hmm. Then again they didn't have 300ish HP.
I believe Mr. Lane's method was to have the backsides of the axles milled so the bearings could be pressed in deeper, and then a spacer was made to space the rotor back out, so not only would the wheel offset be correct, but the caliper would fit properly again as well.
edit: http://www.nellump.net/peri/epi/firs...torsenLSD.html . Also: http://www.jimrothe.com/mazda/torsen.html
Last edited by peejay; Aug 16, 2004 at 10:26 PM.
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From: Behind a workbench, repairing FC Electronics.
Originally Posted by peejay
Now the plot all comes together.
The car in question was David Lane's turbocharged thingus... hell where is David Lane now? Anyway, with the power he had on tap, he was concerned with spline engagement. Other people reported no problems, so hmm. Then again they didn't have 350ish HP.
I believe Mr. Lane's method was to have the backsides of the axles milled so the bearings could be pressed in deeper, and then a spacer was made to space the rotor back out, so not only would the wheel offset be correct, but the caliper would fit properly again as well.
The car in question was David Lane's turbocharged thingus... hell where is David Lane now? Anyway, with the power he had on tap, he was concerned with spline engagement. Other people reported no problems, so hmm. Then again they didn't have 350ish HP.
I believe Mr. Lane's method was to have the backsides of the axles milled so the bearings could be pressed in deeper, and then a spacer was made to space the rotor back out, so not only would the wheel offset be correct, but the caliper would fit properly again as well.
Yup, theres a link around here somewhere. It wasn't pretty he said. He eventually had axles made by Moser Engineering that were longer... I think they go for $300 a pair.
Now I think the thread on my "pig" should be merged in here.
EDIT: I was thinking more along these lins for that link: http://www.rx7.org/jes/axles.html
Last edited by Pele; Aug 16, 2004 at 10:30 PM.
