Gearbox Syncros

[Jetpilot3]

I tracked the car last night and had to shift, pause, then gently put the car into 5th...definately syncros one would think. I'll just get the work done and be over with the tranny issues. Ordering the parts this evening.

enkrypt3d I don't know anyone who does cryo treatment here. I'll look regardless...

I've already got the short gears and 4.23 R&P. People were amazed how hard my car pulls on the front straight of our track.

 

[enkrypt3d]

I tracked the car last night and had to shift, pause, then gently put the car into 5th...definately syncros one would think. I'll just get the work done and be over with the tranny issues. Ordering the parts this evening.

I had this same issue bro - after switching to synchromesh the problem is gone. I would try this while you're waiting on the parts. See how it goes!

 

[DutchBlackNsx]

I tracked the car last night and had to shift, pause, then gently put the car into 5th...definately syncros one would think. I'll just get the work done and be over with the tranny issues. Ordering the parts this evening.

enkrypt3d I don't know anyone who does cryo treatment here. I'll look regardless...

I've already got the short gears and 4.23 R&P. People were amazed how hard my car pulls on the front straight of our track.

A bad 5th synchro is odd, the lower ones usualy go first, but maybe they have been replaced before, and the 5th was not.
You cant get a bad 5th synchro from downshifting, only from skipping gears when upshifting without double clutching into 5th.
I suggest you get the tranny opened first, then check what is faulty, prolly the synchro, but i had problems with shifting into 5th, which was caused by the synchro-spring, and not by the synchro itself.
Since you do have the shortgears installed, i would make sure the procedure for shimming the primairy axle is again followed as stated in the manual. I have seen it time after time people throwing in shortgears, and not following this procedure.
If youre gonna replace the synchro, i would suggest you replace the hub selector and 5th gear as well, its not worth it to find you still have trouble when everything is put back together, you never know.

Just some thoughts..

Mich

 

[Jetpilot3]

Mitch thanks for the advice! I'll notify the shop...

 

[goldNSX]

You cant get a bad 5th synchro from downshifting, only from skipping gears when upshifting without double clutching into 5th.

Quite a lot people do this, they shift from 2nd with 8 rpm directly into 5th. This is very bad for the synchro of the 5th. But I don't see a reason to doubleclutch while going from 2nd to 5th if you go through each gear: 2nd - clutch disengadged - 3rd - 4th - 5th - clutch engadged. This can be done very fast and all synchros three synchros share the task of slowing the main shaft down.

Didn't I read here that a clutch not disengaging 100 % will result in grinding of the 5th first?

 

[jond]

Any suggestions or comments would be great!

I would try GM Syncro mesh first. I did it, and after about 2 weeks of using it, I have no grinds at all(2nd gear used to grind some).

 

[DutchBlackNsx]

Quite a lot people do this, they shift from 2nd with 8 rpm directly into 5th. This is very bad for the synchro of the 5th. But I don't see a reason to doubleclutch while going from 2nd to 5th if you go through each gear: 2nd - clutch disengadged - 3rd - 4th - 5th - clutch engadged. This can be done very fast and all synchros three synchros share the task of slowing the main shaft down.

Didn't I read here that a clutch not disengaging 100 % will result in grinding of the 5th first?

Thats gonna put more wear on your other synchro's. Might as well just wait a sec or two in neutral, and then shift into 5th.