Looking for recommendations for poly locks for use with 302

[Bryan302]

Due to the fact that they don't make things like they use to, and most cam companies have been bought out.  I ask for 69 Z owners to recommend a good poly lock that is reliable and will keep the adjustment well, and with a good quality overall.  I will be using a 140 cam and 3927142 springs and O rockers.  Please give your suggestions on a good brand and the part number.

Thanks,
Bryan

[CNorton]

I've had good success with ARP 12-point Perma-Loc hardware (part # 8241 for 3/8-24 thread studs or # 8242 for 7/16-20 thread studs).   Any poly-lock will work better if the stud ends are trued for a flat surface. the way ARP studs are finished.  A dimpled stud end does not provide a solid seat for the set screw.

c

[69Z28-RS]

I've had BAD LUCK with two different types of poly-locks many years apart; left me stranded both times!   so my recommendation is STOCK CHEVY FRICTION NUTS...  new ones....  they won't move much, and if they do the movement is so slow that you have LOTS of warning, when the 'poly unlockers' come off, they do so VERY quickly.... with no warning whatsoever.. maybe a couple of seconds!

IMO:  poly locks are worse than worthless!

[Kelley W King]

ditto on the friction nuts. My Z is down now with a nasty click. Have gotten the cover off but I kind of know what to look for.

[69Z28-RS]

I don't have pictorial evidence of the first time I had a 'poly locks' failure, as I was driving my '70 Z28 and one came off suddenly.. leaving me stranded until another '70 Z28 stopped to help me (what's the chances of that?)..

But pictured below is the last time I got stranded, my son in law and I were headed to the Good Guys Nostalgia meet in Bowling green KY in 2008 I think it was..  when one of his backed off.. leaving us stranded along I-65.   Fortunately we had chairs in the truck, which made it a bit easier while we waited for the truck/trailer to come get us... and take us back home to get a different vehicle... 

first photo:  It looked good when we started out..
2nd photo:  After only 35 miles up I-65....
3rd photo:  .. waiting glumly....

[motorman]

I have used "PAL"nuts as a lock nut on the std GM nuts

[Bryan302]

Thanks all, for the suggestions and help!

Bryan

[motorman]

Thanks all, for the suggestions and help!

Bryan

also if you do use poly locks set the lash .003 loose ,tighten the locking set screw and then use the adjustment nut to tighten to the correct lash. this wall tighten then poly lock in place. just snugging up the allen lock screw does not do it

[L78 steve]

Poly locks wont come loose if the studs are spot faced as mentioned above. They can be ground flat in an old Sioux valve grinder on the valve stem fixture. If you have valve cover drippers they will have to be shortened also.

[z28z11]

[/quote]

But pictured below is the last time I got stranded, my son in law and I were headed to the Good Guys Nostalgia meet in Bowling green KY in 2008 I think it was..  when one of his backed off.. leaving us stranded along I-65.   Fortunately we had chairs in the truck, which made it a bit easier while we waited for the truck/trailer to come get us... and take us back home to get a different vehicle... 

Looks like somewhere near Ardmore or Lynnville. Glad you made it out in one piece - 

[69Z28-RS]

*L*..  Yes, but even worse...  it was just north of the Elkton exit..