Originally Posted by Monkeyspinner
14 by 1" but I have seen various posts saying about different discs having different offsets and not clearing the flywheel. I have only seen mentioned once a part number of a disc that will work but when I googled it it came back with nothing.

Here is a suggestion. I'm not trying to complicate your life. I hope you see this as simple.
I recommend that you convert the 14 spline input shaft to a Jeep 10 spline input shaft. Then you will be able to use the standard factory 10 spline clutch kit that would be the stock replacement for your truck. The 10 spline Jeep shaft is 1 + 1/8", so it's a little stronger than the 1" X 14 spline S10. Here is a link to my DIY Jeep shaft swap for the S10 T5. I actually had a world class Jeep shaft for the DIY post, but they are no longer available.

Since you have a World Class S10 T5, it will have a fiber style synchro rings. Since only non-world class Jeep shafts are available, you would simply exchange the fiber synchro ring for 4th gear with a brass synchro ring.

If you decide to stay with the 14 spline shaft, then you have several options for discs, but I have no idea which will fit properly for your pressure plate and flywheel. Some of the info I have collected is below.
I just answered a similar question in another thread - so I just copied it below.

This is new territory for me. Some may find it hard to believe, but I have never installed an S10 T5 with 14 splines (only 10 splines after the Jeep shaft swap).

I do collect info to help others however, so I'd like to know the part numbers you are dealing with.
I've spoken to Dave Farwell on a few occasions and he's a great guy and a great resource. Two thumbs all the way up!

I know Speedway Motors sells several 14 spline clutch discs that work with T5s. You would want the largest diameter that your flywheel and pressure plate can handle. Here are some links to the clutch disc at Speedway Motors.

This Speedway disc is 9' which may be too small.

Speedway 10" disc.

Speedway 10.5" disc

Also, these are usually in stock at Rock Auto.
1988 Astro van with 4.3L engine clutch disc — 14 spline and 11”
Option 1: M-PACT clutch systems part # 384212 from Rock Auto
Option 2: SACHS BBD4212 from Rock Auto

Last edited by Lugnutz; 08/25/2016 2:17 AM.
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