T-56 output shaft upgrades (300m?)

A while back a member (silverpig?) had a run of special alloy (I think he called it 300M) output shafts made for the T-56. I am wondering how these are holding up, if other runs are being made, or is there a newer better output shaft that is a stock drop-in (rather than the mods that have to be done for the Viper shaft.

Thoughts?

BBB

Been looking for this..... no luck yet,4yrs.!

I'd look at the Viper conversion if you can't find the 300M. Hell, you could get the Viper in 300M if you wanted.

Check with D&D Performance, Libertys Gears, or GForce Tech for their T56 upgrades. Options include new ratios, triple-syncro upgrades, faceplating the gears (syncro ellimination), steel keys, steel shift fork, the Viper output shaft, a 1-piece assembly, and micronite polishing. There may be more but I can't recall... T56 upgrades are plenty though.

If you're sheering the output shaft the viper upgrade should help. I don't recall all the details on the T56 used in the SSR's T56, but I believe it had larger 1st and 2nd gears and maybe even had a different (larger) output shaft and yolk. It was rated for more torque/load due to the changes (as needed by the SSR's heavy weight).




I havn't heard of anyone "converting" T56 gears to the thicker caddy gears
to reduce throw distance, but the faceplating and triple syncro options should help with that.

If you're sheering the output shaft the viper upgrade should help. I don't recall all the details on the T56 used in the SSR's T56, but I believe it had larger 1st and 2nd gears and maybe even had a different (larger) output shaft and yolk. It was rated for more torque/load due to the changes (as needed by the SSR's heavy weight).

I've got one of the SSR gearboxes in my Impala. It uses higher (numerical) ratios, double- and triple-cone synchros throughout, and a 32-spline output shaft. The shift rail is also slightly different, to accommodate a detent ball in the midplate for fore-aft shift feel. Also, the mounting surface for the shifter is about 0.7" taller.

If you want to use it in an LT1 car, then you either need to swap in a '93 input shaft (and lose the double-cone synchro for 4th gear), or fabricate a spacer. I choose the latter. Unfortunately, there's not enough spline length to simply cut down the input shaft (at least not if you're using a McLeod Street Twin; other clutches may require less spline length).

I've got one of the SSR gearboxes in my Impala. It uses higher (numerical) ratios, double- and triple-cone synchros throughout, and a 32-spline output shaft. The shift rail is also slightly different, to accommodate a detent ball in the midplate for fore-aft shift feel. Also, the mounting surface for the shifter is about 0.7" taller.

If you want to use it in an LT1 car, then you either need to swap in a '93 input shaft (and lose the double-cone synchro for 4th gear), or fabricate a spacer. I choose the latter. Unfortunately, there's not enough spline length to simply cut down the input shaft (at least not if you're using a McLeod Street Twin; other clutches may require less spline length).

Interesting. Still, the input shaft isn't usually a problem with f-bodies (unlike Mustangs that use a dinky 10 spline unit)... the output shaft is more likely an issue initially (well, beyond breaking keys and burning syncros of course :)). Planning for my T56 rebuild has started and I'm seriously throwing around the idea of a SSR tranny... though I already have syncros, keys, shift fork, one gear, and a few other parts for my LT1 tranny (some of which will swap in). It looks like I'll be replacing the reverse gear/syncros/idler since it recently started popping out of gear on its own.

hp ain't cheap... putting it to the ground can be just as bad. :)

Interesting. Still, the input shaft isn't usually a problem with f-bodies (unlike Mustangs that use a dinky 10 spline unit)...

I mention the input shaft only because the SSR box has an LS1-length shaft, and to use the trans with an LT1 requires some consideration of this problem. If you've got a GenIII/IV engine, this is a total non-issue.

A while back a member (silverpig?) had a run of special alloy (I think he called it 300M) output shafts made for the T-56. I am wondering how these are holding up, if other runs are being made, or is there a newer better output shaft that is a stock drop-in (rather than the mods that have to be done for the Viper shaft.

Thoughts?

BBB

I had one of the ones you are talking about. I never got to really test it out before selling the t56 it was in.

I got it through someoen at corvettes of houston.