There was a recent auction on ebay for a described original equipment engine mount GM # 3939728 ( ebay # 300055969592 - it sold for $565.00!!!! by the way) that the seller claimed was original for 69 Z28.
I can not find this number and was wondering what any of the T.C. gurus have to say regarding this mount? My GM parts book dated 1974 shows 3990918 as being the part number for the mount, and there are no superceded numbers listed either.
My 06A Z28 has what i allways thought to be the original engine mounts ( non locking type ) but they do not look any thing like this. I have owned the car since 73, maybe they were changed under warranty or whatever with a previous owner. My car also has the recall warranty fix anti lift bracket and cable on the left side and the cable on the rite. When the cars went for this warranty recall issue did GM change the engine mounts to another updated style and part number ?
Was there any change up in the mount design and part number in later production 1969 Z28,s on the assembly line ?
Thanks in Advance!

Further to my post, I found on page 469 in the assembly manual that shows a stop plate under the LH mount only. It utilizes a longer engine mount bolt with a spacer that goes through the stop plate, to stop the engine lifting if the mount breaks. This spacer goes in front of the engine mount, and the through bolt retains it against the ear of the mount.
I remember seeing this plate on a 69 Corvette before, is this a afterthought also and was this ever installed on factory 69 Z28,s?

Don't know about Zs but my 375 horse 396 had interlocking mounts. Still does. Came with them new. And it was one of the first cars on earth that was recalled because it DIDN'T have interlocking mounts. Figure that one out. I'm sure it was because computers were the new kid on the block. I threw the recall notice in the garbage. I know, shoulda kept it,,,,,. But I kept the CAR!

I always refer to David Pozzi's site for these numbers.

http://www.pozziracing.com/camaro_engine.htm

According to that site, there was no specific mount for a 302. The 350 and the 396 used the same mounts.

I'm totally going to checker after work and buying 10 sets of small block motor mounts. Then I'm going to etch Z/28 in the sides of all of them and sell for $800 a piece as NOS mounts.



Don't worry when I'm super rich I wont forgot where my idea came from!

Thanks for all the replys, but i still would like to find out regarding this strange mount.
Anyone else got any ideas? John Z.? Kurt? Jonesy? Mark?
Thanks Mike.

Who is talking engine mounts and who is talking frame stands ?

The 302/350 frame stands are not the same as a 396. The 396 stands are offset.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&viewitem=&ru=http%3A%2F%2Fsearch.ebay.com%3A80%2Fsearch%2Fse arch.dll%3Fsofocus%3Dunknown%26sbrftog%3D1%26from% 3DR10%26sotr%3D2%26satitle%3D300055969592%26sacat% 3D-1%2526catref%253DC6%26fmmk%3D%26fmmd%3D%26fylo%3D% 26fyhi%3D%26mppfqy%3D300055969592%26sargn%3D-1%2526saslc%253D2%26sadis%3D200%26fpos%3D55803%26f trt%3D1%26ftrv%3D1%26saprclo%3D%26saprchi%3D%26fso p%3D1%2526fsoo%253D1%26fgtp%3D%26fvi%3D1&item=300055969592

To me, this looks like an early small block mounting unit, before the recall. I see in my notes that this is the type of mounting unit to be replaced with the new interlocking unit. I believe the recall happened in 1971. It could of happened earlier, but this is what I remember. The part number could have been superceded with the new part number. I have the same part number as you, 3990918. The style of mount in the auction is not exclusive to the z/28, it was also used on 327 engines and I am sure other small blocks.

Thanks Jonesy, My GM parts book dated 74, also does not show this 3939728 mount in the parts listing and the 3990918 is not a superceded number. The mounts are Group 0.027. This ebay mount also looks unique in that it has a captive nut for the through bolt.
Have you ever seen the stop plate from page 469 in the assembly manual on a 69 Z28 or 396 car? The GM parts book also shows this stop plate in Group 0.002, although it only shows it as being used on a 350 not 302 , funny as the engine mount is listed for 302/350. The GM part number for the stop plate is #3977981.
I remember seeing these on Corvette before, does any one know if the Z28 used them also ?
Anyone got a original car that has never had the engine out? I allways assumed my mounts were original, but maybe this plate was discarded.
Thanks again for all the help!
Mike.