I have my tranny apart to do a rebuild and figured this might be a good time to replace any parts that are especially prone to breaking.

I know anything will break if you have enough HP, but what is usually the 1st thing to usually break with say 350HP/400lbft? Or don't you need to worry with only 350HP?

Thanks

 

There are only a few weak links in a 700 when you start pshing the hp limit. here they are in the order of weakness, at least from my experience.

1. Get a hardened sunshell. TCI makes one called the Beast.
2. get a kit that increases the number of clutches in the third gear clutch pack.
3. Stronger 2nd/4th gear band.
4. While not absolutely necessary, it wouldn't be a bad idea to replace the 4 pinion carrier with a 5 pinion carrier.

of course you do all this in conjuction with a transpack and vette servo.