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Discussion Starter #1
Could an improper fuel injector order cause an engine to act like a rev limiter? I have an old 289 that is running a 302 H.O. firing and injector order. I runs but, around 3500 RPM it acts like thats it like that is red line. I thought maybe if I repinned the PCM that it would run smoother and the full RPM sweep as it should. Is this a possible fix or is the only way to get this to run properly is to put a cam in it? I am running an A9L computer with a C4. Is there any compatibility issuses? I have heard that A9P is for automatics and A9L is for manuals, but mine runs (just not well) just wondering if any of you guys have done this or know anyone who has done this. Any info you have for me would be greatly appreciated...
 

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Discussion Starter #3
289 cam with 302 firing and injector order. I have swapped the plug wires to fire the plugs at the correct time but my fuel "injection" time is off on 4 of the cylinders. baisically, im letting the fuel sit on the intake valve untill it is opened and then it fires... can i rewire the injector order to fix this "rev limiting" issue?
 

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First off, I dont know all the specifics between 289 and 302. The cam could be an issue if the 2 had too big a difference in lift and duration. Im still trying to get back into mustangs and remember what ive forgotten so....My questions would be in this order..
1. when you say it runs, is it running decent up until 3500 or running badly. If the injector timing is off you really wouldnt be able to drive that much, pretty much the same as timing/plug wires being off. I know from experience its a real noticeable difference if you "accidently" do the plug wires for normal 302 vs. H.O.
2. Out of curiosity, how did you figure that the injector timing is off? asking this just cause i dont know how you would do that, im sure there is a way, just never came across it yet. That should all be programmed into the ECU.
3. Im goin go out on a limb with this one and get blasted probably, but if its running somewhat decent and just hits a wall at 3500, check the fuel filter. When i got my 87 it was doing the same thing, once i changed the filter it immediately starting revving the way it should. Mine would rev normal in neutral, but when driving under load, would cut out right between 3000-3500.

Hope somethin here help
 

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thats the problem. 289 and regular 302 have the same firing order. you will need a 351W cam or convert it to the HO hydraulic roller cam. both have the same firing order.it is a wonder it ran at all. your valve events are not matching the computer/injector timing.
 

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Cindy, so what you are saying is that the HO 302 had a 351W cam?? or that a 351W cam will fit into the 289 and work with 302 HO setup?
 

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Yes, 302 HO had a 351W firing order which is 1-3-7-2-6-5-4-8. A regular 302 and 289 has a firing order of 1-5-4-2-6-3-7-8. You'll need your cam events to match what your computer is doing to make it work. Sounds like you are running on 4 cylinders( 1, 2, 6, and 8).
 

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yes, if you want to stay with a flat tappet cam you can use a 351W camshaft. it will fit fine. or convert it over to the hydraulic roller setup with a 5.0 roller cam.
 

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A 302 H.O. I am not sure that Ford ever made one. 302 is the older engine from the 60s and 70s. The engine from the mid 80s to mid 90s that ford used in the mustang was the 5.0 liter H.O. It was called this because it was different and to keep down on confusion. Several parts are the same and several important ones are not the same. People go into a parts store and ask for parts for a 302 H.O. and the confusion continues.
 

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Mathwise 5.0L comes out to 305. Ford still called them 302 though. I knew about the firing order being different between the regular and HO, but didnt know that it was a 351 cam thats in it. Now I know, the thought just never entered that different cam would be needed if the order is different. Good to know now though since mine is the HO
 

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I talked to guy yesterday who had the same problem, only firing on 4 . He changed to 351w firing order, problem solved. The guy ran a junk yard, so he really didn't know which engine he had.
 

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Discussion Starter #13
thanks for the input guys.... i knew the injector order was off, could i repin the pcm to fit my 289 firing order?
 

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I guess it is possible. But then, you have a computer for a 302 HO running a 289... should you decide you want to upgrade or change it in the future you'll have to repin it again...

IMHO, change the cam and call it a day.
 

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Or...better yet...swap in a real 302 HO and ditch the 289 :p
 

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I would be hesitant to try and repin/rewire it just because of the fact of how many issues you can end up with by only messing one up, not saying you would or anything, just a thought. Cam would be probably the best way to go to save yourself the hassle and time. Then again, what David said makes the most sense, just completely switch to a real 302, sometimes makes it a pain when you are trying to do some stuff while working with 2 different engine type setups, if that makes sense. I know Cougars back then ran with 302's so shouldnt be too bad.
 

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Synester, you live in Ft. Walton? I've got family in Mossyhead.
 

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Nice, only been here about 6 months, Used to know people out towards Jacksonville but havnt been in contact for years. Out around Orange Park/ NAS Jax
 

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I know the area. I go to NAS Jax from time to time. I'm stationed over on Mayport NS. If you ever come out this way let me know!
 

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Haha, I'm stationed at Eglin AFB, coming out that way to Orlando in March, trying to convince the wife to let me bring the car, but dont think I will have enough room with kids and luggage, might just have to let her drive her van and I will drive the stang just for fun
 
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