A pair of 1968 350 heads. Originally #17 two barrel. They were cleaned, smoothed casting flash out and crack checked. Then ported using the guidance of Jim Hand from his book and the McCarthy video. A performance multi-angle valve job was done and later the valves were back cut. Pushrod bulge laid back, no tubes. The heads were cut 0.030 to reduce the chambers some, the chamber walls were laid back on the intake side for flow. Finally chamber cc is about 80cc. The stock valves and valve size were retained 1.96 intake and 1.66 exhaust. Springs are Comp cams 995 shimmed properly and good to 0.500" lift flat tappet or hydraulic roller. Rocker studs were converted to screw in studs and have the factory style non-adjustable studs installed. I will include a set of BBC studs for adjustable valve train. Rebuilt and have not been run. I've got $700 in parts and machine shop labor on these heads.
-Stock 1.96" intake valves and 1.66" exhaust valves -Back cut on both the intake and exhaust valves -Intake port openings are standard at 2.08 x 1.12" -Pushrod holes elongated for 1.65 rockers -Crossovers are aluminum filled (piston aluminum) -Stock guide plates -Performance 5 angle valve job with stock 30 degree seat -seat is 87% of the intake diameter @ 1.7" (intake) -stock guides were checked and found in spec -7/16" rocker studs included as well as Stock bottle neck studs -995 Comp springs -Machined guides for retainer clearance and seals -New positive performance seals installed
Compression would look like this (assume 0.030 over bore on all, zero deck and 0.041 gasket, 6.7cc dish)- 455 = 10.9 to 1 428 = 10.3 400 = 9.7 389 = 9.5 383 = 9.3 350 = 8.8 (9.4 with common flat tops) 326 = 8.2
Here are the flow numbers @ 28" LIFT - Intake / Exhaust .100 - 76 42 .200 - 147 90 .300 - 198 122 .400 - 224 144 .500 - 242 160 .600 - 244 167 (these numbers were recorded without putty or a pipe and before I back cut the valves)
In the past I posted in topics on the board about the heads, here are the links-
