A round wire circlip properly is mated into a round section groove, machined with a tool with a round nose, 055 inch diameter or so. I don't think Endplay is the biggest problem.
The Ford SAE report on the big block FORD GT engine development claims they needed 0.005 tp 0.010 to avoid retainer failure that ocurred with less than 0.005 inch endplay. In the 70s every Chevy racer was striving for 0.000/0.010 inch endplay. RE: Piston Pin Retaining Clips Tmoose (Mechanical) 3 Jul 06 14:14 The car that this engine is going into is going to be a "parade queen" and will probably never see this side of 2500 RPM.Īny thoughts or comments would be appreciated. There must be a lot of force at high RPM as race car engine builders like to use 2 spirolox per side.
The questions are ,how much gap is too much? What causes the pin to exert pressure on the clips causing them to pop out? 035 'end play' between the pin and the retainers. The problem is that the retainers I found are.
#WRIST PIN G CLIP INSTALLATION FULL#
These engines did not come with full floating pins, but luckilly, aftermarket performance piston manufacturers used the same diameter of pin with their full floating pins, hence, spirolox and tru-arc locks are available. 912", and as luck would have it, Ford decided to use this same diameter on it's new small block engine, the 289 and 302.
For obvious reasons I do not want to re-use these clips but I have had no luck finding new ones (I have searched everywhere).The pin diameter of the 312 is. These pistons came with full floating pins held in place with a round wire "G" shaped clip. I am rebuilding a 1957 Ford 312 which has very low miles on it and the original pistons are in excellent shape, hence, I would like to re-use them.