Top Dead center is when #1 cylinder is at its upper most point in its stroke
1.8.4.3.6.5.7.2
1,5.3,6.2,4
Firing order is 1-5-3-6-2-4
The firing order for the 4.3L engine is 165432
18436572
the fastest way to tell is if the center intake bolts are not there.the vortec heads that everyone wants for performance have no center intake bolts.
We need to know size engine you have.
I believe it is 18436572 1.8.4.3.6.5.7.2
the fastest way to tell is if the center intake bolts are not there.the vortec heads that everyone wants for performance have no center intake bolts.See link below.
A vortec has bolts in the center of valve covers, instead of around the bottom edge
The firing order for the 4.3L engine is 1 6 5 4 3 2
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