Jim, here it is:

Intake lift .485
Exhaust lift .485
Intake duration 346
Exhaust duration 346
Part number 3849346
Casting number 3849347

Hope this helps.

 

Thanks Scot, that helps. I will not be able to find a original cam, but I need to buy a aftermarket or have one ground. The aftermarket cams for the 302 are 485 lift and 254 duration. I don't know how much of a difference that is between 254 and 346, but I want the original specs, Jim

 

Here is a link to the GM Performance Parts website. They list the Crane Blueprinted Z28 cam that has the original specs. The original cam has 254 degrees duration at .050" lift and 346 degrees 'advertised' duration.
http://www.gmgoodwrench.com/perfpartsjsp/partlist.jsp?cat=9387&section=ep

12364052 Camshaft Kit, Mechanical
Blueprinted replacement for factory P/N 3849346 with 290 hp and 302 cu. in. Z28 camshaft, auto with 4000 converter.

Technical Notes: Basic rpm range is 4000 - 6800; and compression ratio is 11.0 - 12.5. The duration at .050 lift (intake/exhaust) is 254/254 degrees, and the valve lift is .485"/.485". Lobe centerline is 114. This camshaft kit is designed and manufactured by Crane Cam Co.®. It contains one camshaft and 16 tappets.

 

Thanks Neil, that is a big help. I saw one replacement cam that claims the correct intake and exhaust duration is 346/346 ?? Jim

 

12364052 Camshaft Kit, Mechanical
Blueprinted replacement for factory P/N 3849346 with 290 hp and 302 cu. in. Z28 camshaft, auto with 4000 converter.

That must be a misprint. Auto with 4000 converter could have never happened originally.

 

Dr. Dave - That's what is printed on the GMPP website. I believe is it there to help people decide on a cam if they should have an automatic trans. It is not meant to imply that a 69 Z28 came with an auto trans.

 

Originally posted by Jim Neubauer:
Thanks Neil, that is a big help. I saw one replacement cam that claims the correct intake and exhaust duration is 346/346 ?? Jim

That's the "advertised" duration; doesn't take the ramps into consideration, and isn't at .050" lifter rise. 346/346 was the original Chevrolet-published specs, but nobody knows at what lifter rise it was measured.

 

Thanks John and all you guys for your help. I am going to go with 485-254 with a 114 centerline. I hope that works, Jim

 

Hi, I just would like to note, that the lobe centerline must had been 106 in stock trim and not 114 as the Crane brings, and this new trim will make the car more tame to drive, but less rough and rumpty in the idling. Regards