its a pos car my friend has sitting in his driveway.. wondering if anybody knows what the proper firing order is.. 1342? should cap be counter clockwise starting at what would be about 7 on a clock and be 1234 respectivly? any info would be great thanks!
Distributor rotation should be clockwise. I belive you have a Pontiac "Iron Duke" engine, later called a "Quad 4".


Supreme Member
Every 4 cylinder I've ever worked on is 1342.
Vader, you're rarely ever wrong, but the quad 4 and Iron Duke are about as different as you can get.
EDIT: In 1986 I thought oldsmobile went to the quad 4 in which case there was no distributor. There was a coil on each plug and it was fired digitally.
Is this engine a DOHC, SOHC, or an OHV?
If you're confused about the direction of rotation, then just crank the engine and watch the rotor.
Vader, you're rarely ever wrong, but the quad 4 and Iron Duke are about as different as you can get.
EDIT: In 1986 I thought oldsmobile went to the quad 4 in which case there was no distributor. There was a coil on each plug and it was fired digitally.
Is this engine a DOHC, SOHC, or an OHV?
If you're confused about the direction of rotation, then just crank the engine and watch the rotor.
Quote:
Originally posted by ATOMonkey
...Vader, you're rarely ever wrong, but the quad 4 and Iron Duke are about as different as you can get....
Oh, no. You just don't CATCH me when I'm wrong. Originally posted by ATOMonkey
...Vader, you're rarely ever wrong, but the quad 4 and Iron Duke are about as different as you can get....
I understand the "Duke" is a single central cam "OHV" head design, and the "Quad 4" is really a variety of designs, but isn't the '86 "Quad" just a Pontiac 4-holer? Or was it that Chevy 121"-4? Please don't tell me it was that Toyota thingy.
Enlighten me, please, and maybe I'll remember it correctly next time. You may be right about the DIS, but I think '86 was one of those "bastardized" years for more than just the V-8s.
Supreme Member
After a little research I found in '86 you could get the 1.8L or the 2.5 "Duke". So depending on the chassis he could have either. The 2.3L "Quad 4" wasn't inroduced until '88(180 hp!) so we can rule that out. The 2.3 later evolved into the 2.4L "Twin cam" That was available in the Saturns and what not. The 2.4 has a longer stroke, smaller bore, thicker walls, and a balance shaft. The 2.3 and 2.4 heads are interchangeable, but there is a debate over which is better because the 2.4 has higher compression and some of the 2.3 heads have ridiculously big exhaust ports which actually hurt flow. For the most part the 2.3 head does flow more. To the best of my knowledge unless someone came up with a different way to build 4 poppers the firing order is still 1342.
Senior Member
I believe it is a 2.5 Iron, as I read the Quad 4 didn't come out till 88 and is a 2.3L.
So it would be the 1342
So it would be the 1342
yeah its a 2.5 ... k i was just makin sure.. thanks for all the replys guys!



