The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - My 1968 C-20 Golden Anniversary Project

GerhardH · 10-05-2020, 01:34 PM

Found out that the cam is grind (casting number) 930. The GM # is 3896929.
Overlap 90°
Rocker ratio 1.5
Intake timing Opens BTC: 38° (BTC= Before top dead center)
Intake timing Closes ABC: 92° (ABC= After bottom dead center)
Lift .3900" (with 1.5 rockerarm, means lift on the cam is less)
Exhaust timing opens BBC 88°
Exhaust timing closes ATC 52°
Lift .4100" (with 1.5 rockerarm, means lift on the cam is less)
Duration 320°

In my service and overhaul books 1968 327 the lift for inlet and outlet are the same, strange.
camshaft journal ok (1.8682-18692"), surface ok

10-05-2020, 01:34 PM	#153
GerhardH Registered User Join Date: Aug 2017 Location: South Germany Posts: 527	Re: My 1968 C-20 Golden Anniversary Project Found out that the cam is grind (casting number) 930. The GM # is 3896929. Overlap 90° Rocker ratio 1.5 Intake timing Opens BTC: 38° (BTC= Before top dead center) Intake timing Closes ABC: 92° (ABC= After bottom dead center) Lift .3900" (with 1.5 rockerarm, means lift on the cam is less) Exhaust timing opens BBC 88° Exhaust timing closes ATC 52° Lift .4100" (with 1.5 rockerarm, means lift on the cam is less) Duration 320° In my service and overhaul books 1968 327 the lift for inlet and outlet are the same, strange. camshaft journal ok (1.8682-18692"), surface ok Attached Images __________________ Best regards GerhardH! Members met: 68 short step, 68bowtie, 72c20customcamper, botmfedr1, C/10 King, Chevyland, cornerstore, dmjlambert, fun in dirt, GMan69, Ol Blue K20 1968 CHEVROLET C20 Custom Camper 50th Anniversary, Long bed (LB) 8', 327 V8, Air Condition (AC), Power Steering (PS), Power Brake (PB), Z62 Custom & Comfort Appearance, Turbo Hydramatic TH 400 http://67-72chevytrucks.com/vboard/s...d.php?t=760400 Last edited by GerhardH; 10-06-2020 at 06:18 AM.