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Old 06-10-2005, 01:18 PM
454C10 454C10 is offline
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Yes, that is a pretty good cam. However, if you are on a budget you should get a summit cam and lifters for 79.95. sum-k1104 or sum-k1105. Comp lifters are another 86.00.

It is a good idea to run more cam duration on the exhaust valve due to typically low flow ratios (intake/exhaust) on stock exhaust ports, plus heavy cars with small engines like more exhaust duration. (good for a truck with a 350)

The heads sound like a good deal but they still need to be freshened up even through they have low miles. A valve job is really cheap if the heads are in good shape (less than 100.00). Plus I would add 1.5" OD springs with new retainers which will require machining. If the heads have 2.02/1.72 valves, the springs may already be 1.50". I would also install screw in studs. When spring pressure get higher, the studs will pull out if they are the press in type.

Here is how to figure compression ratio:

355cid (+0.030 over 350) is 44.375 cid for each cylinder. (355 cid/8)

44.375 cid is 727cc's (1 cid = 16.387cc's)

CR = biggest volume/smallest volume

biggest volume is: (volume with piston at bottom of stroke)
cylinder = 727 cc
head = 76 cc
gasket = 8 cc
piston recessed in block 0.020" tyipical for sbc = 4 cc
piston recess (+) or dome (-) = flats top about +1cc because of valve relief

smallest volume is: (volume with piston at top of stroke)
head = 76cc
gasket = 8cc
piston recess in block = 4cc
piston recess or dome =?

so a 350 with flat tops, 76cc heads, standard felpro gasket, and the piston in the cylinder 0.020" at top of stroke will have a cr of:
(727 + 76 + 8 + 4 + 1) / (76 + 8 + 4 + 1) = 816/89 = 9.17:1

So, to get 10.0:1 you would need more cylinder volume or smaller cc heads or a dome in the piston.

a 64cc head would give you:
(727 + 64 + 8 + 4 + 1) / (64 + 8 + 4 + 1) = 804/77 = 10.4:1

a 383 cid stroker kit with 76cc head would have:
(784 + 76 + 8 + 4 + 1) / (76 + 8 + 4 + 1) = 873/89 = 9.8:1

a 350 with 8cc dome pistons and 76cc heads would have:
(727 + 76 + 8 + 4 -8) / (76 + 8 + 4 -8) = 807/80 = 10.1:1

A 350 with a zero deck height block (block deck cut so the piston is flush with block), flat top pistons and 76cc heads would have:
(727 + 76 + 8 + 1) / (76 + 8 + 1) = 812/85 = 9.6:1

A 350 bored 0.060 with a zero deck height, flat top pistons and 76cc heads would have:
(737 + 76 + 8 + 1) / (76 + 8 + 1) = 822/85 = 9.7:1

It is always better to use flat top pistons because flame travel is quickest across a flat surface. Domes and dishes slow down flame travel and require more ignition timing advance to complete the burn.

A zero deck block, +0.060" bore, 76cc heads with flat tops might be a good way to go. 9.7:1 will work well with a moderate street/strip cam (220 to 230 degree duration).
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