That makes sense. These are big blocks, with big problems.

Update – I called the machine shop and I was told they where out of round on the base. Which I can understand, they can sleeve them for $600. Then I received more bad news, block #2 has a crack in a cylinder, again it can be sleeved.
I don’t know what I am going to do, it’s hard to find good used blocks. I am thinking about going back to square one and buy two 502 415hp base engines. I wanted more power than that.

Thanks for the responces, I need a drink

buy a couple of Dart Big M blocks they are usually pretty close on machining and you could even get Tall deck ones where you could build some big inch engines then you could still do what you wanted to and probably be cheaper than byu new 502's

[QUOTE=1BIGJIM;3022998]That makes sense. These are big blocks, with big problems.

Update – I called the machine shop and I was told they where out of round on the base. Which I can understand, they can sleeve them for $600.

I was told $300 to bore them to another size, .875, .904, .937.

Dart Big M blocks dont come finish machined. The one I got was all over the place. The material they are made of makes for hard cutting and a lot of heat. My bores were out of round, not top to bottom.. around on several planes. They rough cut them as fast as they can.. The machine shope needs to bring them up to finish.
Unless you can get them from Dart finished, but I dont believe so.??

That makes sense why you can find such good deals on them. Not always but sometimes. You need to spend another 1k for finishing.

what blocks do you need, I have 1 nice 454 std bore, 030 would clean it up, 4 bolt main fresh water cooled marine block, $600, Rob

Friend of mine has a truckload of gm 502 crate motors,450 hp w hyd roller cams, 200 hours or less, complete less carbs and distributors for 1500.00
each
and a few 454's for 1200.00 each

Where they underwater from the hurricane

Looking at the thread here on lifter bores. I started the thread on the lifters and 20w50 oil.
Lifter bores are going to get out of round over time. If you are running a solid or hydraulic lifter, fuel in the oil will cause wear, but you will see that wear on bearings, valve guides and your wheels on the lifters. I charge $500 to lifter true the block that includes the bushings and honing them to proper size for the lifter clearence. You need .0015" between the lifter and the bore. Spending 300 to over size the bore and still run it in cast iron, I believe isn't worth it. If you go to a larger lifter with a larger wheel it is going to change the cam specs. Ask Bob Madara, how much? Any block that has been in service is going to have wear. A new Dart is going to be @ .0012" a Merlin @ .0022" thats already over size. I would stick with my old block and Lifter True it.
Mark

How long do the bushings last ? are they as hard as the block ?