350 Build Up

[Dan White]

I am currently building a 350 for my 66 and have a few questions. I am running a custom ground cam, which has 226 degrees of duration (@ 0.050" lift) and 0.490" of lift on both intake and exhaust. Will a set of crane stock replacement rocker arms (not the ones with the long slot) work with this cam, or will I need to go to long slot ones to avoid interference with the stud? Also, the distributor I was running came out of a 390 hp 427 I believe (vacuum can code 360 12). From what I can tell with a vacuum pump, the can will provide full advance at approximately 13" or 14". Will I need to switch to a different vacuum can, or will this one work ok? Thanks in advance, Dan

[Joe L.]

Re: 350 Build Up

Dan-----

If, by 0.490" lift you are talking about VALVE lift and not LOBE lift, then the stock-type Crane rockers will work just fine. Valve lift is the lobe lift multiplied by the rocker ratio; lobe lift is just the total lift measured at the cam lobe. Most likely, the 0.490" that you're talking about is VALVE lift.

The vacuum control that you have, GM #1115360 will produce a maximum of 12 degrees of advance at 12" vacuum. That should work ok, but others might be better.

[Dan White]

Re: 350 Build Up

Sorry I didn't specify, but you were right, I was talking about valve lift...thanks a lot for your help!

[Dan White]

Another Question - Pulleys

I just remembered another question I had about the pulleys I'm using. The crankshaft pulley sits almost 1/8" in further than the water pump pulley. I dont think another water pump pulley would cure this either, since my current one sits very close to the pump body. By placing one flat washer under each of the three mounting bolts I was able to achieve proper alignment, but I was afraid doing this could affect the balance of my freshly balanced and blue printed engine. Is it possible to shim pulleys like this, or do I need to look for a new set? Thanks in advance, Dan

[Joe L.]

Re: Another Question - Pulleys

Dan-----

Well, you apparently have a mis-matched set of pullies or are using a balancer that is not correct for the pulley set you have. In any event, shimming between the balancer and pulley is acceptable and won't hurt the engine balance. Shims are available in the aftermarket for this from sources like Summit or Jegs. However, I don't see any reason why the washers shouldn't work as well. The pre-made shims are, basically, a large round plate with holes for the pulley-to-balancer retaining bolts.