baddog671

Wondering if I should continue looking for a 31spline unit or settle with a great 28spline unit I recently found. Any guesses on how much HP and TRQ a set of 28splines can handle? I'll probably be getting Moser's, so that should up it a bit.

Car is still in progress, but Im think 350-400HP

Nic

dodgestang

Here is what a a few years and a couple trips to the track did to 28 splines with 330hp at the back tire with an auto transmission no less...YMMV...but if you are buying stuff...by the 31 spline IMHO it will save you in the long run and support you for a long time.

Mustangdemon67

damn, that is scary. maybe ill think about upgrading [&:]

andrewmp6

Dont currie make a 35 spline

dodgestang

Lotsa places make 35 spline setups, but you need a big bearing rear the last time I checked....and I didn't feel like doing that so I used 31 spline instead in my application

67 evil eleanor

I would think that the 28's will handle 300 or 350 HP fairly easy. I think the most important thing is how sticky the tires are as to how much torque it will take to turn them over. Take a good look at the axles, not all 28's are equil. It seems that the older thicker tapered ones are much better.

68EFIvert

I sure hope 28's will work for me. I have a lincoln rear and the axles seemed thicker than another 28 spline rear I had. I am currently installing a supercharger on my little 302 and am told I should have about 450 rwhp. I don't plan on much drag racing so I think I should be fine. I will update everyone if it explodes on me like dodgestang's did.

USMCrebel

its not the HP that kills rear end components, its the torque. you could have 1k rwhp and just enough torque to get you going and would be fine. its that insant snap of power that over torques the axels and they just go boom....ie see pics above

Norm Peterson

It's impact loading that does the dirty work. More of an "instantaneous torque" thing thanthe result of engine torque itself.

Side-stepping the clutch withlots of revs/heavy flywheel/grippy surface is one way. Spinning the tires furiously on snow/ice and suddenly hitting a bare patch is another.

Mythumbnail car with various mildly built 350's (~300 to ~375 hp & torque figures) has had no issues involving axle shafts - and they are only 26-spline pieces. Although I've never been shy about going to WOT once it's rolling, I've never run it at the drag strip and I don't start up hard on the street. (I do suspect that my son snuck it out for a couple of timed runs back when he was in his teens, though.)


Norm

[IMG]local://upfiles/62186/FA87DC18D7A6404C82C3C0DA6803B06F.jpg[/IMG]

zmetalmilitia

This link shows the torque placed upon the rear assembly/tires.
http://www.youtube.com/watch?v=9O0b90G8Yhg