Hot Rods 289 Firing Order Wacky?

Howdy HAMB-ers,
I recently built a 289 from a '66 Mustang and put it in my '63 Comet. Turned out the 60-year-old wiring was on its last legs, so I paid a local shop to rewire and do the motor break in, which they did. I've been driving it and it seems like it runs pretty darn good. BUT...yesterday I pulled off the manifold on the driver's side to grind off a tiny spot that was resting on the steering box. When I put it all back together, I realized this is how the shop had the firing order set up (see pic).
Any ideas as to why they might have set the firing order like this? How could it run alright with this setup?
Thanks y'all!
RNY

 

It has a later model SBF camshaft in it.

 

Yep, 289 is 15426378. 351 is 13726548 Lippy

 

The distributor cap is mislabeled.

 

This is ok bye the way you don’t need to worry about it, it’s all good….

 

Oh man! This is my first motor build and it never occurred to me that the firing order would be different with a different cam...but you nailed it. Just looked at the paperwork and the firing order is correct. Thanks!

 

That got me the first time I rebuilt a later 5.0.

 

Hmmm...I was using a pic I pulled off google labeled "289 firing order" and it shows the Lippy. Gheez.

 

Ford used a few different firing orders over the years on the sbf

and I never trust distributor cap numbering on aftermarket caps . ( one size fits most )

had a young guy here at work fight a 4 cylinder forklift no start for 2 days .

the cap number 1 position was number 3 according to where the engine wanted to be in tdc. He felt dumb, I told him observation is the key to success , never assume .

 

I knew a couple of hard core Ford guys who had had a number of 289 powered rigs each who bought 5.0 Mustangs when they first came out and fought that battle until they figured it out.

 

This may help to explain Ford's reasoning https://www.fordmuscleforums.com/threads/sbf-firing-orders-for-hp.616289/

 

Everything on the internet isn't true.
If your drawing is correct, you have a 351W distributor cap on a 289 distributor.

Joe

 

The distributor cap makes no difference. It’s the camshaft that determines firing order.

That, and there are only two different firing orders as determined by cam valve timing sequence for the SBF, not “multiple”.

Original 221, 260, 286, and pre HO 302 are all the same.

351 introduced a second variation, which was adopted by the 302 HO towards the end of the engine series production run.

 

Quite aware of this but OP says he re-built a 289. If the cap is numbered on the car, per his drawing, it's for 351W and physically interchanges w/ 289 cap, just wrong order on the posts. The wiring routing on his picture is correct for 289.

Joe

 

I learned this one in 1975 when I put a Muscle Parts cam in my 351W powered 69 Mach1. Started right up but was having a spaz attack. The cam was of course designed before 69, firing order changed with the 351W. Took a while to figure out as I never had the wires off the cap. Yep, two firing orders, not "a few"

 

Firing order has made many people scratch their head and wonder what did I do wrong, Fellow hamber Alex called me in a panic wondering why he couldn't get his flathead to run so I made the trip to Greenville the next day to see if I could help.

Naturally it was snowing and freezing cold but we rolled the car outside and started trying to diagnose the problem, I tried several things like checking for spark and plugs and then I started checking the wires, there was the problem, a ask Alex to run through the firing order and he said, 1-8-4-3-6-5-7-2 , I said that would work if it was a small block chevy, the look on his face was hilarious, with in a few minutes we had it running like a top. HRP

 

Only Ford cap I've ever seen marked is only on the number 1 position. Any Ford V8 cap from 1957 to when they stopped producing distributor mounted caps are the same.

 

I believe that all V8s use one of the same two firing orders, they just look different because the manufacturers don't number the cylinder locations the same.

 

I'm currently running a 289 solid roller cam in a '91 H.O. block.

Joe

 

Joe, I think OP was just making a number around his cap v wire location. Or are you saying you have a cap that has actual numbers on it? I’ve not seen one like that, just curious.

 

I don’t ever remember having a cap with the firing order or cylinder numbers on it.

But what do I know?

theoretically you could pick any cap terminal and call it number one, as long as you indexed the drive gear to match.

 

That usually comes from installing the dizzy a couple teeth off and then moving the wires around the cap.
Ford caps are 1 of only a few that call out the #1 position on the cap.

 

Sometimes if you try to move the wires around on the cap and turn the dist you run out of room one way or the other to turn the dist. early chevy six for an example. I once wired up a 413 chrysler 18436572 and forgot the rotation was counterclockwise. Duh.

 

Just commenting on the drawing, if it is correct. I can't remember ever seeing all the posts numbered, as you say (usually #1 only). All we have is a drawing to draw assumptions on, nothing more. Need a pic from under the hood For all I know, someone could have installed a 351W cam in the 289 years ago.

Joe

 

I got tripped up on my 90's model 302 roller cam engine. I wired it with the 351W firing order, just like the books say. What the books don't tell you is Ford also put a different roller cam in some Crown Vics and Mercurys as well as some other cars that carries the old 289-302 firing order. I searched online for a while before I found this out. These engines were roller cam, but not labeled as an HO.

 

Also some Fords (FE?) have a counterclockwise rotation. Not fun when you have worked on tons of GM stuff (clockwise), and then you find out when you "read the book"!

 

Do you mean like the L88 427 Chevy?

The Ford with reverse rotation would be a marine engine from a twin engine boat with counter rotating engines.

The Chevy was simply a gear driven cam instead of chain driven.

 

Absolutely correct. The 302 in my Cabriolet is a non-HO roller EFI (converted to carb) engine from an '86 LTD and uses to older 289/302 firing order.

 

Then there also is the issue of how the manufacturers decided how the cylinders were numbered. At least with an inline four cylinder they all agree.

 

I'll revise what I said above... there's eight possible firing orders for a cross-plane-crank V8 (flat plane cranks are a totally different kettle of fish...), with only three being commonly used on American V8s. As noted, how the cylinders are numbered varies but again, there's basically only two methods used there (there's a couple of oddballs) with the drivers side being numbered 1-3-5-7 front to back, pass side 2-4-6-8 front to back being the most common. Ford uses passenger side as 1-2-3-4 and drivers as 5-6-7-8. Once you 'translate' each firing order into a common numbering layout, the 'Chevy' firing order is the most common, covering most GM, all Chrysler, and about half of Fords. Full article is here for full details...
https://www.curbsideclassic.com/blo...rankshafts-and-firing-orders-good-vibrations/