Input shaft/spline identification

[gtwiss]

Hi all,

I am trying to determine the original application for the transmission/input shaft on
my transmission, a Hewland JFR. The spline diameter and teeth are 29/32 x 17 teeth. The clutch in the
car is an OT 2 Tilton, and I was hopeful to simply subsitute a disc with the appropriate
splined hub and be good to go. If anyone knows what the 29/32 x 17 spline was original
equipment in please let me know. Tilton did not have the tooling to produce this spline
so I am investigating having one made custom for this application by another supplier.

Regards,
Guil

[DaveW]

https://www.summitracing.com/parts/acl-3001101

[gtwiss]

When I put a caliper or micrometer on the output of the trans
I am getting a smaller dimension, about .908, Do you think that
because of the odd number of teeth I am seeing the slightly smaller
measurement than the one spec'ed for the srt4 disc?
Thanks for your input Dave!

Best,
Guil

[J Leonard]

17 spline x 23mm or .940
Wild stab in the dark

[DaveW]

When I put a caliper or micrometer on the output of the trans
I am getting a smaller dimension, about .908, Do you think that
because of the odd number of teeth I am seeing the slightly smaller
measurement than the one spec'ed for the srt4 disc?
Thanks for your input Dave!

Best,
Guil

Just a guess, but some of that difference may just be clearance needed for letting the disc move freely on the shaft.

And you are correct that an odd # of teeth will make the shaft measurement a few thousandths smaller. A calculation of a 17-sided polygon gives 0.932 measurement for a 0.940 OD circle. So 0.932-0.908 means ~0.024" for clearance.

[Phil Creighton]

Is this one of the ex Skip Barber boxes - probably was a dodge if so
Phil