Boring .30 over

I paid $160.00 for a .030 bore and hone with torque plates. This is one area where you do not want to save some bucks and want to make sure that it is done right and I recommend that it be done with torque plates. As for pistons they are going to vary in price. I have a set of DSS racing pistons and they are good quality and not very expensive. I bought a long rod 306 kit that came with forged pistons and rods for $1000.00 but you can get out cheaper than that.

I also went with the 306 setup. I paid $12.00 a cylinder for the bore and purchased the Summit kit. The piston are Speed Pro Hypers with the silkscreened teflon coating on the skirt. The kit came with EVERYTHING. The only thing that you have to also let them know is is you need standard or oversize bearings for your crank and the piston size.

Id just by a new block, boring it at 0.30 isent much at all, thats only 0.30 of a inch, hell a stock piston would almost fit in that.

Striped5.0 said:

Id just by a new block, boring it at 0.30 isent much at all, thats only 0.30 of a inch, hell a stock piston would almost fit in that.

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You should study up on the idea of boring blocks. He will no longer have a 302, he will have a 306. You could NEVER even consider that .030 is not a lot in the tolernaces of an engine block. That small measurment is like a carpenter saying that 1 FOOT isnt to far off. That is how important block tolerances are to the machinist. If you have a good block, then going .030 is the BEST thing to do. You will get the egg shape that the HYPERS leave behind worked out and then you can get some fresh .030 slugs in there. The idea here is to save money AND increase displacment. Get a good machinst and you will be fine.

well how much does it cost to bore it .030 VS buying a new short block?

A new block is about $350.00 + shipping from Jegs. I had my block dipped, flushed, bored .030, freeze plugs installed, and the crank turned turned and polished .010, for $300.00

When you say .030 it is really a raw figure. You cant buy a .030 piston, and expect it to fit in a .030 hole. It would never go in. You have to actually measure each piston, and bore the corresponding cylinders to each piston. Each rod is stamped with a number from the factory. After the machinst places the piston on the rod he should bore that particular cylinder to work with the piston he hung on the rod. Hanging pistons is for the machinst also. They usually heat the pistons up in an oven to expand the metal and then they slam the wrist pins through the pistons and rods FAST because they only have a very limited amount of time. After they cool, they get gauged indivually and each cylinder is then bored to match. Each manufacturer has a tolerance on what they say you should bore to when using their brand of pistons. It is never just one number, always a span from .0?? to .0?? so it is really up to the machinst. It is MUCH better to keep your own block. You take a "seasoned" 302 block that you know is good and any machinst will tell you to keep it. The ones you by from the factory and RAW and they have no way for the engine builder to really get the tolerances correct on placing new pistons in it. Some guys automatically will bore the new ones .030 anyway so they know that the tolerances are perfect for the pistons they are using.

Avg.

$100.00-125.00 for the boring. $50.00 for the dipping, flushing,cleaning. $20-25 for the freeze plug insertion. Much cheaper than a new block.

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Madams summed it all up very well.

Pete