Timing a 75 Pontiac 455

badams_iyns · Nov 1, 2008

Ok, 1st engine rebuild. '75 Pontiac 455. I just got it running and I'm looking to set the timing. I'm told around 35 degrees at 3500 rpm with vacuum disconnected? There’s one line marking on the balancer, and the timing chain cover has a outcropping marking the 4 – 8 – 12 degree marks. How in the world do I tell where the 45 degree mark is? And is my info on the timing accurate? How does one set the timing here? At idle it’s set to 8 degrees.

badams_iyns · Nov 2, 2008

re timing a pontiac 455

Edelbrock PerformeAr plus cam, lifters and intake manifold, performer model 1411 “adjusted for fuel economy” 750 cfm carb, MSD pro billet distributer. Heads say 6H, all new but stock crank, rods, pistons, valves springs, everything including the water pump …etc Plugs gapped at “if I remember right” 50, maybe 60? Pontiac “Ram Air’ exhaust manifolds.

And thanks!

sd2v87x · Nov 29, 2008

455 timing

12 degrees initial at 850 to 1000 rpm - vac unplugged - should put you near 36 total. You will need to listen for spark knock under load but with 6h heads you only have about 8 to 1 compression ratio.

Timing a 75 Pontiac 455

Top Contributors this Month

Recommended Communities