When was this cam first used in the '70 L74 manual trans cars? I seem to recall in April of 1970, but not sure. Was there a dealer bulletin issued?

 

Dan - This guy owns a 1970 Cutlass S w/ QB. Seems to know what he's talking about. Evidently it appeared mid-year>late year 1970 production.

 

Looks like January is the earliest known at the time of this video.

 

The 1970 Engine Assembly Manual has a table of all parts used in each engine configuration. The first page of this table shows that the QB engine data was added 11-24-69. With time lag to get parts to the production line and holidays at the end of the year, January 1970 on the street is not unreasonable. The QB engine was the only 1970 350 to use cam 393859, which is 286/286 deg duration, 58 deg overlap. This cam was originally used in the 1966-67 400 with manual trans.

 

Thank you Joe P. A short and concise answer. No need to watch a 19 minute video of gibberish with no clear answer..

 

Makes sense.


Motor Trend February 1970, Rallye 350 Road Test Quote.

"The camshaft is new to the 350 CID engine, a neat compromise between the stock 250/264° duration cam and the hairy 308° cam of the W31. It is the stick used in last year's manual-shift 4-4-2, which has 286° of duration and 58° overlap with a lift of 0.472 instead of the stock 0.400 inch. Valve spring dampers are also used. The combination has proved such a nice one that it may be used on all manual versions of the L74 for the rest of 1970."
https://over-drive-magazine.com/wp-c...ye-350-1-3.pdf

 

I hate watching ZooTube videos. Seems like every one of them is 15 minutes of somebody who likes to hear himself talk, with 30 seconds of useful info spread around so you have to watch the whole thing. As a result, I don't waste my time on them.

 

Thanks Joe, I should have checked my engine assy. manual first. Shame on me. My thoughts exactly on the video, a lot of talking before getting to the point.