R180

[terry]

How much hp and torque can a 115mm diff take,

 

Thanks

[Zed Head]

115 mm = 4 1/2 inches.  Not very big.  Most of the estimates you'll find are based on what people have seen break a few diffs, or what they've seen them handle without breaking.  I doubt that anyone here has run a 115 mm diff.

[terry]

The rear end I am referring to is a180 out of a Z car.  R180 came in 110mm and 115 inner diameter detentions of the ring gear 

[gnosez]

I run one in my 240 race car and depending on the configuration (I run it as either a 240 or a 280) I am making 245@crank with the L24 and 325@crank with the L28 on 110 fuel.

 

The R180 (115mm) has 4:38 gears and a Quaife. No issues to speak of.

[Patcon]

gnosez

What kind of torque are you making on your motors? It was my understanding that torque was what kills drivetrains...

[gnosez]

Let's just say I might have run an engine that was not legal which had over 350hp@crank and over 300 lbs of torque. No issues. This is a road race car so no launches like in a drag strip car.

 

I also run a 4:44 LSD R190 which is a heavy bugger.

[Patcon]

Thanks

[terry]

_{Thanks gnosez for the information.  Do you know how much race time you have on the 180?}

[gnosez]

I say just under 30 hrs

[John Coffey]

An open two pinion R180 can't handle much torque and will self destruct if you do a lot of one wheel burnouts.  A R180 with a four pinion carrier, or a good LSD (Quaife, OS Giken, Nissan Motorsports, etc.) can handle about 275 ft. lbs. if you run a synthetic fluid like Redline 75W-140 and change it often.

Edited November 23, 2015 by John Coffey

[gnosez]

Quaife and Redline changed out after every race weekend just like John said.

Normal torque for the L24 and L28 are right in the 210-270 range respectively depending on set-up (head, pistons, etc.).

[260DET]

Consider shock loadings too, like clutch dumping. They make a lot of difference.