Is everybody in here frigg'in NUTZ ????????????? $5K.... $6K.... $10K ???????????? Just go BUY a Block brand new from BULLDOG.... $3,975.00 I think ? http://bulldogblockhead.com/ And Yes they are available.... and no offense intended but they are a far better Block than your Cummins ? just say'in.... Re: Your vintage Cummins Block ? If it is still on the 4.190" to 4.250" Rough Bore those are preferred as core shift and wall thicknesses can be an issue.... most builders including me preferring to Sonic map cylinder thicknesses before proceeding to finish the bank corrections 90* and maintain good wall thicknesses ? Once done..... a guy can then make the call how close or "if" it's a good candidate for closer to 4.500" I think if you can get $3,500 for your Block then you are stylin ? Unless of course it's somebody here on this thread wants to give you $5K or $6K ?