1969 qjet fast idle cam

[Jim 25993]

I have been told that in mid 1969 Delco started changing the fast idle cam from plastic to metal.
Can anybody confirm or deny that?
If they did, can you tell me at what serial numbers and or year the changes took place?
Also, how do I identify the correct plastic or metal cams?
I see numbers on all my carb parts, including the cams, but they don't match the numbers in the parts book.
Regards

[Joe L.]

Re: 1969 qjet fast idle cam

Jim-----

The plastic fast idle cams were used in PRODUCTION through at least mid-September, 1969; my original owner 1969 built at that time was originally equipped with the plastic cam. It's possible, of course, that they were phased out and, for some period, both types were being used. Nevertheless, as late as mid-September, 1969, at least one 1969 received the plastic cam.

The plastic cams were GM #7035850 for manual trans-equipped cars and GM #7035851 for automatic trans cars. These were used for 1968 and most of 1969 for both passenger cars as well as Corvettes. In July, 1969 both of these were discontinued from SERVICE and replaced by the GM #7038844 and 7038845 metal cams.

[Clem Z.]

Re: 1969 qjet fast idle cam

joe, where did those #s come from as my 69 delco rochester parts catalog lists # 7036819 for M/T corvettes and 7036820 for A/T corvettes with 350 and 427. did D/R use different part#? i was looking to see if from my parts book i could tell when they changed.

[Joe L.]

Re: 1969 qjet fast idle cam

clem----

GM #7035850 and 7035851 were the original part numbers for the plastic cams. These were replaced by the GM #7038844 and 7038845 in July, 1969. The GM #7038844 was then discontinued and replaced by the GM #7036819 in February, 1984 and the GM #7038845 was discontinued and replaced by GM #7036820. Both the 7036819 and 7036820 were discontinued over 15 years ago. All of the replacements were of the metal variety; only the original '850' and '851' were plastic.

I believe that the GM #7036819 and 7036820 were pre-existing parts when they replaced the 7038844 and the 7038845. This means that they may have been originally used for some other application or they may have been Delco parts system only parts until they were brought into the GM parts system for SERVICE replacement purposes.

[Clem Z.]

Re: 1969 qjet fast idle cam

joe just for the fun of it i checked all Q jets for chevys from 1965 to 1979 and i found 14 different #s for cams. i wonder if they really were different or they just changed the part#