Wrist pin roller bearing end play

[MadBill]

The 700 HP 8,000 RPM 380" SBF we assembled 2 years ago for our road racer ended up for a variety of reasons with normal rod side clearances plus only ~ 0.015" rod to pin boss total end play (we made certain that the latter was not limiting the former) it hasn't been apart since for inspection but it's running great with no sign of any issues. Filters look good, leakdown remains <2% and it holds crankcase vacuum for several minutes on shutdown...

[Kevin Johnson]

If you open up your small end roller bearing side clearances beyond what you have without an appropriate decrease in the big end side clearance to limit canting you will be inviting diagonal end loading of the roller elements which will surely be outside their design parameters. See brinelling. There are roller bearings that can accept these loads such as those used on wheel axles. Forewarned -- check your roller design.

[Notchback]

This was helpful, thanks guys!