Piston to Bore Clearance

[holywood3645]

Hi all
What is the min, max and optimum piston to bore clearance on a 83.5mm bore using Omega forged pistons?
Dave Bean specifies a range in his book of
0.0035 to 0.0040 for RR58 alloy and
0.0045 to 0.0060 of an inch for TRW forged pistons. (page E9)

I have some Omega forged with following sizes: ( I have a new set of 83.5 rings)
83.38312
83.37550
83.38566
83.37550

I need to verify the bores but I asked the machinist to bore to 83.5

Will these work ???
Thanks
James
[email protected]

[rgh0]

The clearances will probably work OK in a 83.50000 mm bore but it depends on your use and on the actual piston material and design. The piston maker will normally give you a specific recommendation on clearance ranges for road or race use. If not the aim mid range for road use and at the large clearance end of the range for race use. I have never used Omega pistons so dont know what they specifically recommend.

I would love to have your measurement tools and climate controlled metrology lab - accurate to 0.00001 of a mm is nice to build an engine to.

cheers
Rohan

[elansprint71]

......
I would love to have your measurement tools and climate controlled metrology lab - accurate to 0.00001 of a mm is nice to build an engine to.

cheers
Rohan

As would NASA.