JDM tranny owners, RPMs at 80 MPH in 5th
#26
development
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just so I don't have to search...yes, it's Friday I'm lazy and curious...when I take my JDM tranny apart, how many teeth = .806 and how many = .762.
?uestion of the day
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#29
Originally Posted by dgeesaman
Just count the teeth on the gear and pinion and divide.
I'm going to guess:
.762: 45/59
.806: 50/62
Dave
I'm going to guess:
.762: 45/59
.806: 50/62
Dave
Dave
#30
development
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okay...I have 27 and 53 for fifth gear, now I need to count input shaft and countershaft but what will the equation look like? Thanks.
also anyone know where I can get a new blocker ring for whatever 5th I have?
also anyone know where I can get a new blocker ring for whatever 5th I have?
#33
development
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better question, does the updated 5th gear blocker ring have all the teeth? and does it fit the JDM tranny.
The one I picked up in the FS section doesn't fit but is very different looking than the one in the tranny. I did notice REVERSE has all the teeth and 5th did not.
am I making sense?
The one I picked up in the FS section doesn't fit but is very different looking than the one in the tranny. I did notice REVERSE has all the teeth and 5th did not.
am I making sense?
#34
I can tell you that the 5th gear syncro from my JDM tranny fit the USDM 5th gear perfectly. I don't remember anything unusual about it--I think it had all of its teeth. Having held a US and JDM 5th gear side by side, I didn't see or measure anything that was different other than the ratio, i.e., the gear tooth counts (not the dog teeth--they are the same). I do not know for fact that my JDM syncro is the updated part; however, given that it much newer--post 96 for sure--I assume that it would be.
#35
Originally Posted by dubulup
better question, does the updated 5th gear blocker ring have all the teeth? and does it fit the JDM tranny.
The one I picked up in the FS section doesn't fit but is very different looking than the one in the tranny. I did notice REVERSE has all the teeth and 5th did not.
am I making sense?
The one I picked up in the FS section doesn't fit but is very different looking than the one in the tranny. I did notice REVERSE has all the teeth and 5th did not.
am I making sense?
I believe the old and new 5th synchro design have teeth going all the way around; the difference is the material.
There is no correlation between the number of dog teeth which engage the synchro and the number of gear teeth. So there would be no reason for a different synchro for the JDM and USDM ratios.
#36
development
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thanks for the help guys...I don't know the year or km's on the tranny, but everything looks good...5th synchro and 2nd synchro are the only things that looked like they should be replaced...to expect another 50k-75k miles (which would take another decade at this rate).
I ordered both synchro's, lock nuts, and seals from Ray...they will be here tomorrow, we'll see what the hell is going on here.
I ordered both synchro's, lock nuts, and seals from Ray...they will be here tomorrow, we'll see what the hell is going on here.
#38
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Originally Posted by Speed of light
I think it had all of its teeth.
#40
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#46
my sources -->https://www.rx7club.com/3rd-generati...os-you-984896/ this thread would of probably given you your answer LOL
Last edited by Tem120; 11-15-13 at 08:38 PM.
#47
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Jack the rear of the car off the ground, release the parking brake, pull a plug from each rotor, put the trans in 4th, hand crank the engine and measure rear wheel rotation for at lease 10 revs of the engine, do the same in 5th.
Thus you can calculate your diff gear ratio and 5th gear ratio.
Put the car back on the ground and measure the rear wheel/tire radius.
From all of this you can calculate theoretical rpms vs speed.
Find a stretch of road with mile markers, use that at a set speed to verify real speed vs speedometer speed. Or use GPS to measure speed vs speedometer.
It appears many are not good at math and problem solving. No wonder the forum and USA is falling apart.
Thus you can calculate your diff gear ratio and 5th gear ratio.
Put the car back on the ground and measure the rear wheel/tire radius.
From all of this you can calculate theoretical rpms vs speed.
Find a stretch of road with mile markers, use that at a set speed to verify real speed vs speedometer speed. Or use GPS to measure speed vs speedometer.
It appears many are not good at math and problem solving. No wonder the forum and USA is falling apart.
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