5.0HO to 5.0

hey i blew my old 89 motor in my lx, and had a thunderbird 5.0 none HO in my shop. Nw I got it in and used the thunderbird computer in my car. Amazingly it works. I idles fine but runs like a dog, and misses when you get on it. I get no check engine lights. I guess i just need to find an HO motor, but this is the only one I got right now. Any input would be great. thanks.

Matt
 
  • Sponsors (?)


you did not mention what year t-bird engine you had. most t-bird engines use a standard 302 firing order and batch fire for the injectors. a standard 302 firing order is 1-5-4-2-6-3-7-8. 302HO/351 firing order is 1-3-7-2-6-5-4-8. if you have a standard firing order cam and have the wires set up in a HO/351 firing order, that would explain your lack of performance and miss problem. batch fire is where the computer fires bank 1 injectors(all injectors on the passenger side:1-2-3-4) at the same time then fires bank 2 injectors(drivers side 5-6-7-8) after that. the A9L computer is sequential fire meaning that it fires a single injector when it is needed for a HO application. if you still have your old cam from your mustang you can just swap them the t-bird engine. make sure that the cam you take out is a roller cam. if it has a flat tappet cam your steel dist. gear will tear up the teeth on the flat tappet cam. i do have a spare 89 302HO cam if you need one. hopefully you have a mass air computer. it would be a good time to put a diff cam in if you have the money. the only major difference i've seen between the HO and non-HO engines is the intake and the cam. the heads should still be the e7te-pa heads unless it is a 86 engine. i hope this helps.:nice:
 
you did not mention what year t-bird engine you had. most t-bird engines use a standard 302 firing order and batch fire for the injectors. a standard 302 firing order is 1-5-4-2-6-3-7-8. 302HO/351 firing order is 1-3-7-2-6-5-4-8. if you have a standard firing order cam and have the wires set up in a HO/351 firing order, that would explain your lack of performance and miss problem. batch fire is where the computer fires bank 1 injectors(all injectors on the passenger side:1-2-3-4) at the same time then fires bank 2 injectors(drivers side 5-6-7-8) after that. the A9L computer is sequential fire meaning that it fires a single injector when it is needed for a HO application. if you still have your old cam from your mustang you can just swap them the t-bird engine. make sure that the cam you take out is a roller cam. if it has a flat tappet cam your steel dist. gear will tear up the teeth on the flat tappet cam. i do have a spare 89 302HO cam if you need one. hopefully you have a mass air computer. it would be a good time to put a diff cam in if you have the money. the only major difference i've seen between the HO and non-HO engines is the intake and the cam. the heads should still be the e7te-pa heads unless it is a 86 engine. i hope this helps.:nice:

that's was totally what i was going to say next :bang: :D
:hail2: ed:hail2:
 
wazazzle - I just used to much Nos on a 170,000 mile motor and the heads are done. I was just putting this one in so I had a car to drive, and I'm going to build my old one up.


Now for the rest. it's an 86 non HO motor. I have two stock HO cams laying around. So your saying if I put an HO cam in, I can go back to running my HO computer. By the way it's an A9P mass air. I don't have E7's heads to put on it. I just happen to have a Map sensor so thats all it running on right now with the 86 T-bird comp.
 
wazazzle - I just used to much Nos on a 170,000 mile motor and the heads are done. I was just putting this one in so I had a car to drive, and I'm going to build my old one up.


Now for the rest. it's an 86 non HO motor. I have two stock HO cams laying around. So your saying if I put an HO cam in, I can go back to running my HO computer. By the way it's an A9P mass air. I don't have E7's heads to put on it. I just happen to have a Map sensor so thats all it running on right now with the 86 T-bird comp.

i think you'd run into a problem if you decided to use the e7te heads. because the 86 302 motors have true flat top pistons with absolutely no notches for valve clearance. here's a pic of the 86 true flat top piston.
 
wazazzle,
thanks for the compliment.
lordmustanggt,
you have three things wrong with our engine. cam, pistons, and heads. i would just change the spark plug wires to the non-HO firing order and call it good till you build your other engine. that would seem like the cost effective way of doing things for now. if you have the money why don't you build up a stroker 351?
 
wazazzle - I just used to much Nos on a 170,000 mile motor and the heads are done. I was just putting this one in so I had a car to drive, and I'm going to build my old one up.


Now for the rest. it's an 86 non HO motor. I have two stock HO cams laying around. So your saying if I put an HO cam in, I can go back to running my HO computer. By the way it's an A9P mass air. I don't have E7's heads to put on it. I just happen to have a Map sensor so thats all it running on right now with the 86 T-bird comp.


Is this non HO motor a roller motor? I assume you hooked a vacuum source to the MAP sensor...? The E6's used on the '86 HO motors were a one-year-of production head. I mildly ported a set of e7's for a friend who put them on an '86 Mustang. We used stock valves, there was enough clearance.
 
I have no clue yet if it a roller or not yet. I did change it over to the standard non HO firing order. IT RUNS! it just donesn't run good when you put you foot in it. it idles perfect. just is a dog when you put you foot into it. feels like it missing but it not. I've checked plug wires MANY times. everything is good. It feels like a pinging motor, but its not. If anyone has a good HO block with heads still on it for cheap let me know. I also have everything from my 89HO motor on this one, injectors, all harness, fuel pressure reg. and I put a knock off edelbrock intake on it made for the 86-95 HO motors. I don't know if thats too much for it. Maybe it getting to much fuel, but I don't know without a wide band. This just sucks, lol

Ya the vacum line is hooked up to the map. Maybe there's something about the harness from a t bird and mustang thats keeping it from running right under power. I would just love to shove a stock motor in it a drive it for now.

Matt
 
I have no clue yet if it a roller or not yet. I did change it over to the standard non HO firing order. IT RUNS! it just donesn't run good when you put you foot in it. it idles perfect. just is a dog when you put you foot into it. feels like it missing but it not. I've checked plug wires MANY times. everything is good. It feels like a pinging motor, but its not. If anyone has a good HO block with heads still on it for cheap let me know. I also have everything from my 89HO motor on this one, injectors, all harness, fuel pressure reg. and I put a knock off edelbrock intake on it made for the 86-95 HO motors. I don't know if thats too much for it. Maybe it getting to much fuel, but I don't know without a wide band. This just sucks, lol

Ya the vacum line is hooked up to the map. Maybe there's something about the harness from a t bird and mustang thats keeping it from running right under power. I would just love to shove a stock motor in it a drive it for now.

Matt

The T Bird computer is probably not compatible with your harness. I cannot write this with total conviction, but I know that the Mass Air wiring harness from an '89 Mustang is the only harness that works as a plug-in with the 87 and 88 Mustangs when converting to mass air. I don't know the history of your car either, is it Mas Air? What year? Did you convert it to Mas Air? ...You probably need to switch some wires on the computer plug, but I have no idea which ones to switch. If you still have the T bird harness, you could compare the plug-ins, etc.

Changing the cam should allow you to convert back to the H.0 firing order, and allow you to use your A9 computer. If the T bird engine isn't a roller motor, you would need to get a cam from Delta Cams: a flat tappet with the desired firing order. I have a 351 flat tappet cam with the desired firing order, but I don't know if the cam brearings are the same diameter. Delta could tell you if the cams are interchangeable. I also have some stock 351 cams lying around... I'd give you one... I do have a running 5.0 from my 82GT. It is 50 oz imbalance like your motor, but it is not a roller motor and has the older (non HO) firing order.

If you are not too invested in performance parts for your 5.0 it might be a good time to switch to a 351. It has a 5.0 firing order, it costs no more to rebuild, it's stronger, and it has more torque. You would need a different (28 0z imbalance) flywheel. I don't have a 351 that is ready to go, but you could probably get one (rebuilt) from Waterhouse or ... I do have a flywheel.
 
the 351 and 302 cams will interchange. i have put a flat tappet 351 cam in my buddies 66 mustang with a 289 in it. i also have a roller 351 and put a 89 HO cam in it. I'm just mocking things up in it and it does fit and spins smoothly. one easy way to check if your engine is a roller cam or not is to measure the pushrod length. the roller one is 6.250", the non roller will be much longer due to a shorter lifter. do not know the length of a flat tappet pushrod though.
 
the 351 and 302 cams will interchange. i have put a flat tappet 351 cam in my buddies 66 mustang with a 289 in it. i also have a roller 351 and put a 89 HO cam in it. I'm just mocking things up in it and it does fit and spins smoothly. one easy way to check if your engine is a roller cam or not is to measure the pushrod length. the roller one is 6.250", the non roller will be much longer due to a shorter lifter. do not know the length of a flat tappet pushrod though.

Non roller 351 is 8 inches, plus or minus .2
 
OK everything makes sence now.. I was just trying not to pull the manifold again to check. My car used to be the 4cly auto and bought a mass air harness and computer off ebay. So it's a mass air car. I'm going to go out tonight and pull everything, and if it's roller I'll shove my stock ho cam in there and everything should work fine again.

Switching to a 351 was an idea i though of. If this doesn't work I might do that. I've never heard of waterhouse? Are they local. Would you suggest a roller or solid motor and what years do the roller 351 start.

thanks for everyones help so far! it sucks when you only have one car.

Matt
 
roller 351 i think started in late 94 i believe. i got mine out of a 97 E-250. the availability is getting better as more 94 and up trucks and vans end up in the wrecking yards. it takes time but you can find them.
 
roller 351 i think started in late 94 i believe. i got mine out of a 97 E-250. the availability is getting better as more 94 and up trucks and vans end up in the wrecking yards. it takes time but you can find them.

I would buy one if given the choice between a non roller, but they're not a high priority. I drill my blocks for the Ford factory spider that holds down the dogbones that keep the rockers aligned, then just get a small-base-circle cam.
 
i agree with you john. however the roller 351 just fell in my lap and i could not pass it up for a song. did not even have to pull it out of a van, i just loaded it up in my truck and took it home. just got luck i guess.
 
OK got the thing together with a stock HO cam, baby started RIGHT UP! purd like a kitty. :nice: freakin waterpump is leaking though,.... maybe it has to do with the bolt being gone on one side cuz they always brake off. those of you that know, know what I mean.