Is it ok to buy a clutch disc for use with the same JWT PP I've had for a while now?

should be.

It depends on the level of wear on the PP. If it's just glazed, you can use a street disc (with a marcel spring) with the PP once it's been sanded. Yes, you will have to take a grinder to the surface of the old PP to remove glaze. 200-400 grit should be fine. If the PP has any vallies or grooves, replace it. ACT makes a great 42% over PP and JWT sells a 30% over. These are both outstanding PPs for street discs, even factory. Both these PPs work well on turboed cars also.

Cossie

you should never put a grinder to the surface of the flywheel or PP.

Done it in the past with no ill effects as long as the disc has a marcel spring (never done it without marcel). Just a surface buff is all I had done not really a grind that's why I state "If it's just glazed". If too much grinding is done you will get chatter. There are some shops that have the equipment to properly resurface PP. I prefer that people buy new also, but some times we are short on $$.

Cossie

thats great if u have done it in the past with no ill effects, however, grinders are way too agressive and it is imposible to determine if the surface you grinded is perfectly flat. Its just like your brake rotor. Proper procedure is to resurface it on a lathe, not grinding it with a grinder.

I see your point. I suppose not everyone has the wherewithal to properly deglaze a surface with a grinder. That's why it's best to have a pro do it (if you are going to do it). Best to buy new then. The question was...
"Is it ok to buy a clutch disc for use with the same JWT PP I've had for a while now?"
It is ok if the surface is proper, not the easiest wrought though. In the past (my youth) it was ok to have it resurfaced by a pro etc..., but today it has been ingrained that one must not use an old PP. So be it.


Cossie

Have you ever tried to hand sand a disc? It does not work. My hand got a bit tired and the disc was not even scratched. It's very easy to use the grinder. You just guide it, no downward pressure, and keep it moving around the disc over only the glazed areas. One should stop sanding areas that are scuffed. Take it to a machine shop with the proper equipment if you have any doubts.