90HP 60 degree Piston size question

[carolinaflare]

1998 60 Deg 90HP Loop Charge J90SLECM

Hello all, Quick question regarding replacement piston brand and size.
I am rebuilding my motor due to low compression on 2 out of 4 cyl. I know what caused the compression problems and have fixed it, (previous owner sank it). I have stripped the block and had all 4 cylinders machined .020 over original to remove scratches and blemishes. The outboard machine shop guy told me that if i plan on using Wiesco replacement pistons it should be machined 1/2 a thousanth bigger than the book requirement to allow for the forged Wiesco piston to "swell". I agree judging by his experience and the overwhelming talk about this online.

My question is- The block has now been machined to .020+ 1/2 a thousandth. I have found a new set of .020 oversized pistons that are OEM J/E , not wiesco. Would it be safe to put those pistons in the motor instead of the wiescos? the manual shows a +/- .004 tolerance for bore size so im thinking that the .0005 of an inch isint that big a deal. The reason for picking the OEM pistons is totally price, I can get them new through a buddy of mine for about 40$ each, vs 110$ each for the wiesco.

Thanks for the advice.

Tyler

 

[racerone]

If the factory says that pistons are for 0.020" O/S than the bore needs to be 0.020" O/S as well.----So go ahead and fit those factory pistons with no further work to the bores.

 

[carolinaflare]

The problem is that the bores have already been done with the extra half thousanth.

 

[racerone]

0.0005" is not a problem, not in any language.-----After all 0.0005" is fairly hard to measure at home.---This comes from someone who has done work with calibrated gauge blocks where numbers like 0.000010" are mentioned !!