Overbore my 502?
10-29-2018 | 10:01 PM
#2
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From: SF Bay Area
That question starts with whatever the machine shop is willing to stand behind. I’m all for leaving as much material in the block as possible but I don’t think many factory blocks are machined with torque plates, which may be nice if you’re going for big power. JE makes an .002 oversized pistons that you can hone to which is how I’d go about it if the bores are in good shape.
Edit: I don’t know if they make .002 pistons that fit stroker cranks though.
Edit: I don’t know if they make .002 pistons that fit stroker cranks though.
10-29-2018 | 11:56 PM
#4
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From: yorkville,il
4.5 is a common overbore but on a lot of blocks that is as far as you can safely go.once the engine is warn to the point the cylinder bores are no longer round and have excess taper the block is useless and will need to be replaced.for this reason i always recommend the smallest overbore to make a good cylinder,this way down the road when it needs to be bored again the block is still usable.the problem is the avability of a off the shelf 4.480 or 4.490 piston.most people will buy the 4.5 piston and not worry about the next rebuild because they save some money buying the shelf stock piston.
10-30-2018 | 04:11 PM
#7
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From: NW Michigan
That can vary from block to block as well as what rods and bolts are used. Typically doesn't take much when needed from what I remember when spending some time years ago at speed/machine shop I use. .060 plus clearance ok.
10-30-2018 | 06:07 PM
#8
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From: Waldorf, Md
Like the others said "it depends" If the bores are perfect (very very rarely) then you could get away with just honing. Personally I would probably plate hone .005" over with custom pistons and let the cubic inches be a little smaller. I prefer the cylinder wall thickness. Gives a touch more room between the cylinders to help seal the head gasket too. 99% of people will never notice the difference between a 540 and a 535 You might see it on the dyno but even that is doubtful.
10-30-2018 | 07:24 PM
#10
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From: NW Michigan
My HP Siamese bowties I had could safely be bored out to 4.560 plus after sonic tested. Casting numbers ended in 1106 or 1107. I read somewhere years ago that gen 6 4.530 max. Pretty certain that came from foxwell. Always good to leave some room without a doubt. Sonic test to be certain or just bore minimal with torque plates as suggested. 10-20 CI isn't going to have any real worthy gain worth the risk.
