cam selection

If I deck (I.e. Lower) the heads and/or block, the heads will ride lower. Even if I lower each head the same distance, the intake will get 'pinched' as the heads come a fraction closer (nearer the center of the crank means closer together). That would mean that any decking of the heads/block would result in a need to deck the intake manifold. Am I thinking wrong here?

I'll get the heads back next week and will be able to dry fit everything for inspection. I'll take pics of everything so we're not relying on my 'superior' mechanical descriptions... :sosp:
 
Don,
that is correct if you try to 0 deck the block. But if you only compensate for the thicker hg the geometry stays the same. That is why the dry mock assembly is so important. If your piston is in the hole .020 the cut for the hg will "0" deck and you will end up with a perfect quench distance of .040-.045"

the fact of the matter is even an extra .020 from the deck won't be that much if need.

Robert
 
Robert kenney said:
don,
but if you only compensate for the thicker hg the geometry stays the same.
Robert
Click to expand...

"I see," said the blind man. "as I spit into the wind, it all comes back to me..." that makes total sense, duh.

What's a reasonable cost for the decking work? My machinist is well respected, but his price to grind the exhaust humps was very reasonable. I'd like to have a data point before he and I talk turkey on the decking.

Based on the discussion above, the difference in height due to the composite head gasket is ~.023". So that sounds like what needs to go in order to bring it back to 'stock' compression. Then a bit further to up the compression? Obviously the dimensions are all dependant upon what I measure on the dry mock-up, I'm just trying to get the steps straight.
 
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Decking prices are not standard but iirc I payed $45.00 to deck .020 from the last sbc I built. Do it once after mock up measurements. Then maybe the heads will need it also but the block should be first.

Rk
 
I have decided that I'm not going to do any decking, but rather just roll with it. I think the compression will be good enough for now. This is no hot rod, and I'm itching to get the truck back on the road.

Jeff, I haven't heard anything on the order but I think you said the comp cam, lifters, and bearings were in stock... I'm hoping to have the cam, lifters, bearings here by Thursday (maybe Friday) afternoon if possible. Joe and I are trying to do the engine swap this weekend.
 
thedon said:
I have decided that I'm not going to do any decking, but rather just roll with it. I think the compression will be good enough for now.
Click to expand...


Don,
in this case you should make sure the intake lobe center line is @ 104-108 installed. I think the cam you purchased is 110 but May be ground with 4 degrees advance built( intake lobe cl of 104) in it as this is comps mo. The cam card should say.

The advancing will help preserve cylinder pressure that you will need.

Robert
 
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