Originally Posted by popo1984
Ok guys i was given a zz383 cam by a friend and have decided to use it in my 383. 72 c10 swb 200r4 3.73:1
383 zero decked
16 cc dished pistons
dart 200cc heads 64 cc
rpm air gap
670 vac sec avenger
should be about 9.8:1 scr
i initially decided to use a 276h which is 224/230 @ .050
but since I was given the zz383 cam which is 222/230 .509/ .528 lift I have decided to use it. my question is since I am having to buy rockers anyway should I go ahead and get 1.6 rockers.
Crane grinds this EXACT same cam under part number 119831. 2000-6200 power range, good mid-range torque and hp, fair idle, moderate performance useage, mild bracket racing, auto trans with 2500+ converter, 9.5 to 10.75:1 static compression ratio advised. Timing events 4/38/52/-2
1.6 on the intake will yield 0.543" lift, 1.6 on the exhaust will yield 0.563" lift. Make sure you have enough valve spring. Check for piston to valve clearance, retainer to guide clearance and check the springs for stacking solid at that lift. Also, if you use conventional (non-roller trunnion) rockers, inspect the relationship between the rocker slot and the rocker stud at full lift. They make long-slot rockers to cure interference problems.
On the DynoSim combos that I play with, 1.6 rockers will usually add less than 10 hp, while significantly increasing the stress on the valvetrain.
That cam will make some pretty good cylinder pressure with those heads and intake, so make sure you have the squish tightened up (0.035" to 0.045").