Piston Pin weight difference
Thread Starter
Staging Lane
Joined: Oct 2003
Posts: 83
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From: Land of the lost
Piston Pin weight difference I received beautiful new tooled pins... but four are 140 grams and four are 147 grams. Seems obvious I got a mixed batch. Anyone know if this is typical differences, or, like me, feel I got a mixed set???
I can shift faster than you.
iTrader: (21)
Joined: Nov 2001
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From: Baton Rouge, LA
Take a micrometer and measure the diameter of the pins. You could have got four .927" diameter pins (which work with most of the SBC connecting rods) and four .945" diameter pins (stock pin diameter). The difference in the two pins is ~ 10 grams.
If they are all the same diameter, I would call the manufacturer and find out what's up. They should not vary much at all in terms of weight (definitely less than 0.5 grams).
If they are all the same diameter, I would call the manufacturer and find out what's up. They should not vary much at all in terms of weight (definitely less than 0.5 grams).
Originally Posted by JamMasterJ
Your kiddin right. This is tooled steel... the machine shop will charge a half day for that.
Thread Starter
Staging Lane
Joined: Oct 2003
Posts: 83
Likes: 0
From: Land of the lost
I'd rather not dog the manufacturer, but there among the best. For a 15k motor I'm not about to grind away myself, though I will do the build. Besides, the machine shop has everything, I really dont want to go get the pins, bring them home...grind and return.
LAstLS1: Why does a machine shop have to balance the pins you ask? When a 700 plus HP motor is on the line, all should be on par. Any part not perfectly weighted will be ground accordingly. Down to the bolts. Lots of mallory is likely needed anyway due to the super heavy duty rods (direct from Childress).
The pins are all the same diameter. Thanks for the valuable info though Jason. I assume the manufacturer will replace 4 of the 8. They are closed till monday, and I just wanted to know if this was uncommon...and i was gonna be bitchin about a usual discrepenancy. I do learn as I go, seems to be the most fun and educational.
LAstLS1: Why does a machine shop have to balance the pins you ask? When a 700 plus HP motor is on the line, all should be on par. Any part not perfectly weighted will be ground accordingly. Down to the bolts. Lots of mallory is likely needed anyway due to the super heavy duty rods (direct from Childress).
The pins are all the same diameter. Thanks for the valuable info though Jason. I assume the manufacturer will replace 4 of the 8. They are closed till monday, and I just wanted to know if this was uncommon...and i was gonna be bitchin about a usual discrepenancy. I do learn as I go, seems to be the most fun and educational.
Last edited by TwinSpin; Jan 2, 2004 at 11:27 PM.
