thanks guys for the info
someone else told me I should be good in a light car as well which makes me feel a little better about it, I'm going to try to not add too much weight as I'm still working on the chassis. I think I'm going to get the upgraded D Drum since it's the piece that is always breaking for others. I wish there were more upgraded aftermarket parts. It seems I'll never be able to increase power of my car with this trans.
this is the aftermarket part they're saying is stronger
http://www.youtube.com/watch?v=L3fD-lYHpdA&feature=plcp
reverse d drum brakes where it's holding snap ring and clutch pack. Does this affect other gears or just reverse? I don't see where else is an issue as far as it being weak.