I was running 6.90s in the 1/8 in a 3400 pound car(driver included)with 1.60 60's,with a stock flexplate.Est. about 625-650 hp.I put in a tci plate for peace of mind,but don't think you'll have a problem breaking any of them with your power level.Of course,if you over build now you'll be ready to go when you build that alky injected 540
.Safety first.You only have one set of toes!!