GM 3.1L V6 (Pontiac Grand AM etc) firing order??

[Jon K]

Can someone tell me the firing order on a GM 3.1L V6 - I bought coil packs for wasted spark setup and the coil units are labeled (1 2 3 4 5 6, duh) but I know its a V6 and I want to see if the firing order is different and thus whether I should ignore the markings on the coils.

Coil A has outputs to cyl 1 & 4
Coil B has outputs to cyl 3 & 6
Coil C has outputs to cyl 2 & 5

Whereas M50 is 1 5 2 6 3 4 I believe.

[Ross]

The firing order is 165432 hook it up as per your post. The coils fire twice per revolution. When 1 is at the firing position it's paired cylinder(4) also fires at the end of it's exhaust stroke,atc.

[Jon K]

Right, wasted spark, but because the M50 is a different firing order I have to ignore the numbers printed on the coils and pair 1 & 6, 2 & 5, and 3 & 4, right?

[Ross]

Are you using the General's coils on the M50?
I don't understand what you are trying to do. The M50 is still going to need six coils. Right?

[Jon K]

I want to avoid getting into detail about what I am doing yet - the M50 does not need 6 coils, it needs 6 firing spark plugs... if you use a GM coil pack (wasted spark coil pack) which is a 3 tower coil, meaning 2 leads per coil, thats 6 spark plug leads, then it does not need 6 coils, no.

[Ross]

What is going to trigger the coils?

[fujioko]

Jon,

This made my brain hurt. I mapped the sequence according to the BMW firing order of 1 6 5 4 3 2. My map indicates that you should pair 1&4, 2&5, 3&6. Ironically it’s the same as markings on the coil pack. My logic could be flawed.

Based on 720 degrees of crankshaft revolution for one firing of a cylinder. (four stroke
engine of course)

The six cylinder engine would map out with 12 equally spaced segments at 60 deg each.

If we imagine that cyl #1 is at 720 deg then cyl #4 must be at 360 deg then one and four are at TDC. Since #1 is firing then #4 must be at the top of exhaust stroke.

Due to valve overlap and timing, I suppose it would be possible for the wasted spark on #4 to ignite fuel in the intake manifold.

So if the above suggested firing order doesn’t work then ??

[joshua43214]

MY HEART! MY HEART, OH MY GOD, my HEART!! HERESY HERESY HERESY. Your car will never forgive you for putting a GM part on it, it will sneak out at night and let itself be used as a felony get away car and lead the police on extended high speed chases that will be seen by the entire nation on prime time as a nationwide manhunt is conducted for the "Americas Most Wanted" owner. It will then run away to a non extradition country with a riced Honda it met while on its crime spree leaving you holding the bag.

lol just fooling with you Jonk, Good luck with the project, can't wait to see the movie of it on the track.