What is a reasonalble limit for an SFI approved stamped flexplate as far as power and weight (BBC, T400)? Anyone ever hear of someone breaking/cracking one? I'm sure they all come from the same place (ie B&M, TCI, are all the same) most likely.

They're SFI approved for a reason. That's what makes them legal (and safe) for NHRA / IHRA rules.

Most of the aftermarket ones you see are all pretty good and you could just about pick one out of a hat and be satisfied. They'll take plenty of HP.

I think once until you get into the really quick ET's then there is a different SFI rating for those HIGH HP combos.

Rob

I must add that a flexplate usually takes a dump because of a mis-aligned starter.

I've never broken/cracked one but I need to buy better than the minimum requirement next time. My last two flexplates only lasted a few runs each as the metal spread out where the converter bolts go through. They would last a long time, but whenever I had a pass with intermittent traction it would clang when I got out of it at the top end!

Yes, after the first time, I made sure that everything was alright, torqued and loc-tited properly. Still spread it like butter.

I have a converter with 6 lugs on it now but I'm still going with a better one this time and still using 6 lugs to spread out the load (paranoia)