How can I tell if I have a 400 or a 460 in my 78' Ford F250 Ranger?

I'm not a mechanic / technician but I do know that the 400 and the 460 have

different firing orders :

The 400 firing order is ( 1 - 3 - 7 - 2 - 6 - 5 - 4 - 8 ) Counterclockwise rotor , and the

460 firing order is ( 1 - 5 - 4 - 2 - 6 - 3 - 7 - 8 ) counterclockwise distributor rotor

so if you look at the spark plug wires on the distributor cap and # 1 and then the

next spark plug wire is # 3 so they both go to the passenger side of the engine it

would NOT be the 460 cubic inch

( On both engines the # 1 position on the distributor cap faces to the REAR and slightly towards the drivers side )

( On both engines the cylinder / spark plug locations are numbered : )

firewall

4 - 8

3 - 7

2 - 6

1 - 5

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