It is a T/A block - can be bored 100 over and since I have a T/A challenger without an original block there is resto value for me to put the unit into the car, unless of course you are perhaps aware of an original T/A block which is available - cheap? (Just teasing, not available and if they were they would not be cheap) Also, according to my machinist type friends, it is very possible to bore and sleeve the block successfully. Otherwise your thoughts have merit, thanks for taking the time to respond, I do appreciate it.