Will using 86.20mm rings work on a 86.25mm cylinder work?

[trad1987]

My block was bored to 86.25mm when it was rebuilt. I am putting in new rings, but cannot find any of that size. The closest that I can find are 86.20mm from Nissan. What would you guys do? Thanks

[Jtuned_andy]

you're supposed to have the machine shop bore the cylinders to match pistons and rings, take it back and have them do the work properly.

[mademedoit]

Find some vids on the net of someone test fiting new rings in a block. What you do is place just the ring in the block and with a feeler gaugle measure the gap, usualy about 2 or 3 thousanths of an inch are the specs if the gap is to small there is a special tool witch is basicly just a hand crank with a rough diamond blade to file down the ring. I would not sugest hauling your block down to an engine shop and asking them to bore it an extra .05 mm :)

[TheWolf]

If you can't read the guys question carefully. Don't Offer Technical Advice.

His block is 86.25MM. His rings are 86.2mm The ring package is TO SMALL! NOT THE HOLE!

The ring package you are talking about is designed for a .002" smaller hole. The result of running this ring package on a 86.25mm piston is that the ring end gaps would be substantially bigger. About .010" larger than stock. If you have already purchased this package then place each ring in the hole about .5" down in the bore. Use a piston to push the ring another .5" or so down in the bore. Use a feeler gauge set to figure out how wide the gap is. It should be about .008-.010" larger than stock. If it's smaller than that then you should be happy as then you could used them. Running ring gaps as large as above will result in more blowby and less compression but could be used if none could be found. A gap that size would be fine in a motor that see heavy drag racing duty with nitrous or high boost (25psi). If you can not find anyone with a set for your piston then find out the ring widths and call manufacturers of rings. Try and order them by size. Push comes to shove. Order 86.5mm rings and use a ring file to get the gaps down to the size you need. Where did you find 86.25mm pistons? That's quite an odd size.