Big help: What is the firing order for a big block 427 1979 gmc truck - Help.com

Should be 1-8-4-3-6-5-7-2

left(drivers in US) 1-3-5-7 right(passenger in US) 2-4-6-8 from front to back And looks the same for HEI and points ignitions

you sure? for a chevy 427 BB?

according to Haynes 67-87 chevy and GMC 2wd/4wd

yeah, the firing order is as you said.

that describes what looks like an impossible firing order, Not to be mean, CandP.

front of car
———–
1 2
3 4
5 6
7 8

okay, that is showing how they are numbered…on the cap, the wires go in the firing order.

1-8-4-3-6-5-7-2

top center is 1.
2 1
7 8
5 4
6 3

****, tha was suppossed to be a circle
anyway, starting at one, you attach the wires to the cap in the order going clockwise..

what you described is the origin of the numbers that you need. :)

trust me on this, Godfather a mechanic, 40 years experience, I called him to ask.

trust me, there is NO firing order anywhere for an 8 cyl that goes 13572468. there would be no way, the pistons on oppisite sides would be firing too closely to actually generate any thrust at all…it would never crank over.

try again, the cap, where 1 is top dead center

—-1–8—–
—2—–4
—7—–3
—-5—6

this is the firing order for that engine, and on an engine that old, it might be hard to see the imprint on the block..this is not a guess, guys.

the plug points are numbered thusly,

1 2
3 4
5 6
7 8

that is where you get the origin of the numbers for the firing order, which cannot be the same as the plug line-up on the engine.

I really hope I am not offending, but i think either the manual has a misprint, or is not making the info clear

nono! sorry that is the location or number of the cylinders not the firing order! the **** thing wouldn’t run if that was the firing order

HAHA for like five minutes you had me convinced I was crazy.

wait, now I confused myself.

—-1–8—–
—2—-–4
—7—-–3
—-5—6 1-8-4-3-6-5-7-2 firing order 13572468 cylinders in order from driver front around to passenger front