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Old 10-17-2011, 10:22 PM
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When I was in Phoenix and had my other computer there, I used to do quite a few dynosim combinations for some of the fellows on here. One of the nicest liittle 350 builds used #12407 RHS bare heads with valves, seals, springs, retainers and locks in a kit, all from Competition Products. The intake runners are 170cc. Use the 1.94"/1.50" valves in a street motor.
http://www.compcams.com/Company/CC/c...x?csid=72&sb=0
I'm thinkin' the heads complete are around $700.00 or a little more. You can't rebuild your junk heads for that.

355 Gen I Chevy street motor, 453 HP, 475 ft-lbs torque.
Block: '68-'86 Chevy 350 Gen I bored +0.030".
Crank: Stock 350, 3.48" stroke, 2.450" main journal diameter.
Rods: Stock 350 5.7". Recommend ARP bolts, re-size big end.
Pistons: Keith Black hypereutectic, part #KB193, 12cc D-cup, 5/64,5/64,3/16 rings. 1.561" compression height. Gap top ring 0.026", second ring 0.018".
Heads: RHS Pro Torquer Vortec 170-64, 2.02" intake, 1.60" exhaust. These heads will accept either conventional or Vortec type intake manifolds. They are drilled and tapped for both types.
Intake manifold: Dual-plane, high-rise such as the Edelbrock RPM, Weiand Stealth or Professional Products Typhoon.
Carburetor: Vacuum secondaries 750 CFM.
Headers: 1 3/4" primaries, long-tube, equal-length. Install "X" pipe between collectors and mufflers. Run 2 1/2" pipe to the rear through mufflers of your choice.
Camshaft: CompCams flat tappet hydraulic 260H: [1], installed straight up.
Rocker Arms: 1.6 ratio on both intake and exhaust.
Static Compression Ratio: 9.6:1
Dynamic Compression Ratio: 8.4:1
Squish: 0.035" to 0.045". Zero piston deck height with 0.035" to 0.045" head gasket or 0.010" to 0.020" piston deck height with Victor Reinz #5746 head gasket that compresses to 0.025".

RPM HP TQ 1000 59 310
1500 103 361
2000 150 395
2500 192 402
3000 246 431
3500 306 459
4000 360 473
4500 407 475
5000 442 464
5500 453 433
6000 450 394

Stock converter and stock rear gear will work, but would be more fun with a converter that stalls at 2000 to 2200 rpm's and a 3.73 gear. The most out-of-whack spec on this build is the fact that RHS flows their heads on a 4.200" pipe. The resulting flow numbers bear little resemblance to real-life flow on a 4.030" cylinder bore. If you want closer to real, multiply these hp/torque figures by 0.95.

If I were going to build this motor today, I'd use a Howards hydraulic roller cam with about the same cam timing events.

Last edited by techinspector1; 10-17-2011 at 10:30 PM.
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