Hey all! I have the opportunity to buy a 454 block, but it has a sleeve in it. It is a 440 sleeve,and the guy told me he had it put in because he wanted it .040 over, and a 440 bore is close to the 4.290, .040 bore, therefore he would only have to take like .001 off or something like that. Have any of you heard of this before, or done it yourselves? As I have said before, I want to make about 500h/p, from the motor, so I need to know it will handle it. He said the sleeve wall is still about 1/8" thick. It is a 2 bolt, and is nothing but a block. He is asking $350, worth it? Thanks for any and all help.