Author Topic: Old vs. new style BB mounts  (Read 1304 times)

Mike S

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Old vs. new style BB mounts
« on: July 18, 2012, 02:21:59 AM »
  While replacing the motor mount bolts with new ones I noticed they are almost 1/2" shorter so the nuts don't have enough threads to properly hold.
The ones I removed were 4 1/2" grade 8 hardware bought ones I installed in the mid 80's along with the new motor mounts from Chevy at that time and the bolt length was just right.
Looking at my other L35 survivor that has the old style mounts (without the safety tabs) I see they are narrower so these bolts would fit if I use that type.
  In keeping with restoring correctly down to the correct bolts I researched and see the old style mounts are made again as repos (without the safety tabs).
My drag days are long over so I was thinking of installing the older style mounts being I'll only be using the car for shows.
Has anyone else encountered this problem with the bolts and also does anyone use the repo 'old style' mounts?

Thank you in advance,
Mike
67 LOS SS/RS L35 Hardtop - Original w/UOIT
67 NOR SS/RS L35 Convertible - Restored

1968 Z28

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Re: Old vs. new style BB mounts
« Reply #1 on: July 18, 2012, 01:37:21 PM »
I have a complete set of the two styles of motor mounts and the hardware.  I got the longer bolts, washers, and nuts from GM for the safety tab ones and the shorter bolts are the original hardware.  Just haven't decided which to use yet.  Been wondering if you get dinged for using the later safety mounts as opposed to the orignial production line mounts.  Have you heard anything about this?
Jerry G.

Z28-1968-07C-Norwood
Ermine White, Red Std. Interior
2nd. Owner, 38,000 miles

JohnZ

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Re: Old vs. new style BB mounts
« Reply #2 on: July 18, 2012, 05:26:20 PM »
Been wondering if you get dinged for using the later safety mounts as opposed to the orignial production line mounts.  Have you heard anything about this?


In NCRS Corvette Flight judging, the later safety mounts get a minor deduction; don't know about Camaro judging - the standard/scoring criteria isn't published.
'69 Z/28
Fathom Green
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Mike S

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Re: Old vs. new style BB mounts
« Reply #3 on: July 19, 2012, 01:59:16 AM »
 I see LI Corvette has the repos. I'm going to head over there during lunch with the later style I have and compare them.
I've decided I'm going to use the old style being the car will not be beat on anymore.

Thanks for the replies,
Mike
67 LOS SS/RS L35 Hardtop - Original w/UOIT
67 NOR SS/RS L35 Convertible - Restored