Piston Pin Fit
 

I am rebuilding a 74 2.7 and 2 of my Anusil cylinders were bad. I was at a Porsche swap meet and bought a set of RS pistons and cylinders, which I was told had 20K miles on them. The cylinders are Nikasil and are in great shape and all the gaps and clearances on the pistons and cylinders check out within limits. My only question is with the piston pins, I can push them in and out with my finger. There is drag on them when I push on them, but it is not an interference fit. Is this okay or what should I be looking for?

Good question,
Have same experience on my 2.2e pistons. Set coming out of car pin moves freely and 4 of 6 measure good, new used set the pins are so tight I suspect I'll have to heat the pistons to get them to move.

Anxious to see the experts chime in.

FWIW, the pins from a *new* set of 95mm Mahles I just installed, slid in without any undue force. A good thing, IMO.

I was hoping that was the case.

I believe there is a spec for pin-to-piston pin bore clearance. Measure them. If not to spec, have a machine shop hone the piston pin bore for the correct piston pin clearance. Identify the pin so it installs into its fitted piston.

Ditto with pin-to-con rod-small end clearance. Refer to the other thread, "Inserting pistons into cylinders".

Hope this helps,
Sherwood Lee
http://members.rennlist.org/911pcars