My buddy's co-worker bent a valve due to a broken valve spring, He learned the hard way running a cam over .500 lift on stock springs at 6000rpm isn't that good of an idea. The shortblock is fine but the stock heads are shot. He wants to buy my Thumper heads with double valve springs, as is, for $550. I will in the mean time save money for a set of AFR 165's most likley. It might take me until March to get the cash for new heads. When all is said and done, will I be glad I waited??? (I have a second car) I'll probally run it with the B cam and regular performer intake for a while before I get the RPM upper and a cam matched to my combo.