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Piston fit

1038 Views 2 Replies 3 Participants Last post by  bigblok86ranger
When my block was being bored .030 over the machine shop waited until I got my pistons before they did it so they could finish hone according to the piston size. If I'm going to reuse the same bore size (still looks pretty new)
but with different pistons (also probably different brand) do I need to remachine the block?
Is there enough difference in pistons to cause a problem?
I am switching from dove heads to scj, currently using probe pistons, not sure yet what the next ones will be.

question 2: are the rods measured center to center or end to end?
I haven't been able to find my reciepts with part numbers and for some reason I think I remember having 6.7" rods but with a 4.3" stroke crank. From what I can tell most everyone else uses 6.7's on a 4.5" crank and 6.8's on the 4.3, so I'm either going to need custom pistons or new rods and pistons.
I may have to wait till fall to take them out and measure to be sure.
Thanks in advance for any help you can give.
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There can be variances withing the same brand too, so you're just going to have to measure the clearance and go from there.

Rods are measured center to center. Probe makes a piston for the 4.300/6.700 combo, so that's probably what you have. You might be better off selling the rods and pistons you have and replacing both vs. having a custom piston made.
If you remember or can find the piston part number Probe has pistons that use 4.3 stroke with 6.8 rod and use the same piston with 4.5 stroke with 6.7 rods but also have pistons that use 4.5 stroke with 6.8 rods and also have pistons that use 6.7 rod with 4.3 stroke. If you know the piston part numbers and your stroke you can figure out which rods you have. Or another option is call probe they may still have your info on file;), for warranty purposes.
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