"F" 250 as the ultimate tow rig! Can it be?

[Lightningbird]

I have been throwing around the idea of putting a 8KC t-bird computer in the truck, use a car injector harness and move a few pins in the truck harness and viola, SFI speed density. No more batch fire. I think it may be worth a few MPG. I also have the A9P computer from when my tbird used stock ford 5.0 302 parts to make it down the track. I also have a 93 Cobra computer and MAF I could use, just requires to change the cam. Maybe use the custom 393 Schneider hyd roller cam I got made for low end? Your thoughts....anyone.

[TurboCoupe50]

SFI speed density. No more batch fire. I think it may be worth a few MPG.

Don't get your hopes up, SEFI mostly addresses emissions... If it would have increased MPG I'd think Ford would have used it in trucks sooner than the early '90s... The converted to mass air Stang I had lost .2 ET at track but did pick up approx 1mpg... I wound up converting it back to SD...

[Lightningbird]

Thanks Tom, I was wondering if it would make a difference. Looks like it may be worth trying it before dropping $750 for a tune on the truck. I have found the fueling limitations of the stock computer. Maybe the 393 would be better because the RPM band may be better suited for towing vice this smaller 351 motor that easily turns up to 5K. I may try playing with fuel press before all. Seems like its running rich at idle surprisingly, 24# injectors may be too much. I used thin rings 1.5/1.5/4mm package with the napier setup and the H series Clevite bearings that had less bearing surface. It may not need so much fuel at an idle. After putting it together it only took 15 in/lbs to turn the motor over with no plugs. It may be fueling too much at idle.

[Lightningbird]

Tom, this is what I was looking at that seemed to make a lot of sense.

http://www.fordmuscle.com/archives/2...sion/index.phphttp://www.fordmuscle.com/archives/2...sion/index.php

[Lightningbird]

Ok, so ZF 5 speed conversion has not gone so well. First off, I had to make a harness for the transmission, not all that bad. Then I swapped the column that I got from the junkyard, it had a bad ignition switch that took 2 days to troubleshoot and narrow down the switch itself. That was difficult because I had messed with so many things making the harness I truely thought it was the harness but turned out to be the switch. That was most likely the cause of the junkyard truck being in the junkyard. Lastly was the transmission leaking tranny fluid out of the input shaft. I thought the front seal did not end up sealing. After taking the tranny back out, I found that the pilot bearing was too sloppy in the crank allowing the input shaft to work the bearing loose. This was a problem! Usually the crank is junk at that point or can be used for an automatic, but I bought the old school bushing for a SBF and dimpled it with a punch to swedge the bushing into place. I know this is a work around, but easier than the crank being changed or manufacturing a custom bushing, so thought I would try that first. I have not got the tranny back in yet as I had to take it out to replace the seal and verify all was good internally. Had to replace a synchro on 3-4 shift to correct damage from input shaft wobble. It should be back together soon and I can test it out.

[Aerocoupe]

Its been over a month so just wanted to check and see if you had made any more progress.

[Lightningbird]

Its been over a month so just wanted to check and see if you had made any more progress.

A few things have come up, tranny rebuild X3 until I finally got the ZF right. What a bear! My father died unexpectedly. Really slowed things up quite a bit. I do have some more updates and a few pics to throw out there. Just been stupid busy!

[Aerocoupe]

Oh man, sorry to hear about your pops...that really sucks.

Sounds like the trans was an unholy battle. Anything in particular kicking your butt or just one of those Pandora's box slash Murphy's Law deals? No rush on the replies as we know you have a plate full.

[Lightningbird]

If you look a few posts back, I thought the pilot bearing was toast....turned out that the input shaft had been slightly bent or warped. This took me forever to find and fix. I ended up dropping a few grand into the tranny at a shop to figure it out. I was not so happy about it....but what do you do? I had the tranny in and out about 5 times. What a bear! This thing ain't a T-5, it has some gerth to it!

[Lightningbird]

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