Author Topic: sprial piston locks  (Read 707 times)


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sprial piston locks
« on: September 05, 2017, 10:13:08 PM »
Hello, I need help on tips to installing spiral locks in full floating pistons.


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Re: sprial piston locks
« Reply #1 on: September 06, 2017, 12:00:28 AM »
It's been awhile for me, but if I remember correctly, a pair of needle nose pliers to carefully grasp the 'squeezable' part, squeeze it just enough to get it in the pin hole and in the groove, and release.  Then the other side..  Make very certain you have the rod/piston orientation CORRECT...   and if your parts are numbered that you match up piston and rod...    Once the spirolock is installed, I like to 'rotate' it in the groove a little to make certain it's seated fully in the groove.

PS.  hint...  oil slingers go next to the journal, NOT facing the sister rod...   (I took apart an LT1 once that some 'fellas' had installed them backwards...  :(
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Re: sprial piston locks
« Reply #2 on: September 06, 2017, 01:54:40 AM »
Another good way to make sure of the rod orientation is to keep the larger chamfer on the rod to the fillet radius on the crank journal. Might bind if you don't - the 302 crank carries a really decent fillet on that side for strength - almost .125".

Spiralocs are a pain. I tossed mine and used Circlips -

1968 Z28 M21/U17 BRG/W
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Re: sprial piston locks
« Reply #3 on: September 06, 2017, 12:47:13 PM »
Do not reuse them. 

Assuming standard sized grooves designed for single retainers....Insert just the tail and work it around down into the groove.  it will not rotate.  Sharper of the 2 edges faces out while smoother edge goes toward pin.

MUCH harder to get them out of the grooves.