camshaft question
 

does the 1968 high performance L34 396 use a camshaft with the grooved cam journal?

Re: camshaft question
 

No, I think it was 65 and/or 66 only.

ALbert

Re: camshaft question
 

Thanks Albert, That's what I thought. I just got a nos L34 cam #3883986. that is the part number for a 1968 hi perf L34 396, but it has a grooved cam, so there must be two differnt cams with the same part number.

Re: camshaft question
 

I'm no expert, but I believe that camshafts that were used in applications spanning the pre-1966 and post-1966 period were the same in all respects except for the journal groove. For example, the 3863143 (casting 3863144) L-72 camshaft has the identical grind for a 1966 Corvette (with groove) and a 1969 COPO Camaro (without groove). I also understand that a grooved cam can be used in a later application, but that a non-grooved cam cannot be used in an early application due to oiling problems.

Anyone care to comment? https://www.yenko.net/ubbthreads/imag...lins/dunno.gif

Re: camshaft question
 

Jeff, That is correct, you can use the cam in later applications but for 65/66/ and early 67 blocks the camshaft MUST have the groove otherwise top end oiling will be comprimised.
The easiest way to tell if you need the groove is to inspect the rear cam bore in the block- if it has 3 holes in the block after the brg. is removed it MUST have the groove.
If the block has the full annular groove in the block the camshaft does not need to be grooved.
Please note that i have seen early "351" 427 67 blocks with the 3 holes and no groove, not sure about 396 blocks.
Also there are specific cam brg sets for the early blocks- SH615S for 65/66/67 blocks and SH616S for the later blocks mid 67 and up. The only difference is the rear brg.
Hope this Helps.
Mike.

Re: camshaft question
 

Good info, fellas...I found all this out the hard way a couple years ago. If I remember correctly one side of the top end wouldn't oil? Anyway, we yanked out the cam, Moparts put in his lathe, and then we were set...

Re: camshaft question
 

Learn more and more each day https://www.yenko.net/ubbthreads/imag...lins/blush.gif

ALbert

Re: camshaft question
 

I did the same thing on 65 396. I used a drill and old dist shaft to check oil pressure. No oil to the lifters. OPPS! https://www.yenko.net/ubbthreads/imag...lins/beers.gif