I recently inherited my grandfather's 73 F100 390 and I want to restore it but my current plans won't allow that right now. I can however spend some effort getting it running decent so I can drive it. I want to use it in the winter and put some miles on it but the three speed sucks for driving any more than a couple of miles. Is there an overdrive trans that I can bolt behind the 390 or should I just get a small block and trans out of a newer truck. I'm actually leaning toward making it a little lighter on the nose with a 302 or 351 from a early to mid 90's truck so I can have a serpentine accessory system and just put a carb on top. Money will be tight though so keeping the big block, which runs fine just needs some gakets, might be more economical up front.

 

What 3 speed do you have and what ratio is your rear end? What exactly do you mean by "the three speed sucks for driving any more than a couple of miles." You also didn't say if it was an automatic or a manual, 2wd or 4wd

Unfortunately, you are not going to find an OD trans that will bolt to a FE. You can make a NV4500 manual or an AODxx/4R70W automatic work, but its big money for either the swap kit or the core trans (or both in some cases.) You might get away with finding a NP435 4 speed to give you another gear, but its still going to have a 1:1 4th gear.

If your heart is set on overdrive, it might be cheaper to find a good late model and swap the drivetrain and associated goodies out of it. If you go with a Windsor smallblock (302/351w) overdrive options are nearly endless... and sources are all over the place. Everything from Mustangs to Crown Vics, not to mention Broncos and other F series trucks.

 

FORD F150 diesel doug nash overdrive DNE 2 C6 DNE2 | eBay

overdrive units are the easy way out if you can find a useable one on the cheap. Obviously the driveshaft would need to be shortened ($60-$100)

 

That DN od must be pretty rare. I know my forgetter works hard, I don't recall reading about that one.



John

 

Its a 3 speed auto 2 wheel drive and I mean unless I plan on driving surface streets and backroads the engine is howling at anything above 55. Not only is it loud and annoying its extremely inefficient. I have plenty of wrench time on small blocks and it sounds like that might be the best way to go for what I want out of the truck. I'll poke around a bit and look for info on a small block swap here on the site but I think the only real issue I will have is hooking up a newer ac compressor to the old parts on the truck. Cooling system will not be much of an issue, and as far as I know all I need are the small block motor mounts and a custom driveshaft.

 

What axle ratio is in it? If you have a 9", those are "easy" to change.

As for the FE, figure you get a 20% increase in mpg--which would be a stretch. You are still at what, 12-14 mpg under the best conditions?

BB power is nice to have, but the price is steep with $4 gas....

 

Jo,
The Doug Nash units are not that rare. They became the basis for the US Gear under/over.

 

an overdrive unit that will bolt to a C6 and costs less than the Gear Vendors?! The junkyard hunt begins...

 

This is a Hone overdrive that attaches directly to the 9" rear. I have it on my 75 F100, 390, 4sp, 4.10. Shift on the fly for a 30% gear reduction. makes those long trips on the highway almost affordable.

 

Hone overdrive, look under "H", next to "Hen's teeth":

http://www.stangerssite.com/honeodrive.html

 

Wow that hone is slick but I'm definitely leaning toward a small block swap. I'll keep it carbed for now, but I'll save the EFI stuff for a future upgrade. I do want EFI on it eventually but first I want to be able to drive the sucker.

 

Find a wrecked 5.0 Mustang/Bronco/Exploder/F150 and get the engine (and maybe the trans?) out of it. Get all the wiring and fuel injection stuff and put it in the garage and put a Performer RPM intake and a vacuum secondary 600cfm carb on it and watch it FLY! The roller cam 5.0 engines are really nice! Exhaust should be simple as any F100 302 headers should fit, but might get weird depending on the year/source of the donor 5.0 (later Exploders had what Ford calls GT40 "P" heads, and the exhaust ports are a little different.) The entire engine is almost a direct swap for a smallblock and the serpentine stuff is actually pretty easy to work with. Watch out for the oil pan, you may need to switch to a period-correct oil pan and pump pickup for your year truck. Power steering may complicate things, as will the distributor & timing. Do what you can to re-use the dizzy because IIRC the roller cam requires a STEEL dizzy gear. Mismatch the dizzy gear and cam and all hell breaks loose. FYI: I believe firing order on the 5.0 is different than the 302, you might want to look into it, or at least be aware. Electric fuel pump and fan will be mandatory. Look up the 5.0 Mustang 3g alternator upgrade and the dentside T-Bird/MKVIII electric fan upgrades and do them at the same time. I always recommend the Carter GP4070 because its simple, dead reliable and requires no regulator. I did this same project with a friend, but with a '67 Mustang. We carb'd a 89 5.0 from a Mustang and bolted to his stock C4. He was able to pull down 20+mpg on a regular basis with his freeway-flier gearing. We never got around to installing the EFI because the car ran great with the carb. I always thought this would be a hell of a bunch of fun in a 2wd F100.

Good luck, and start a build thread while you are at it!

 

Excellent post man. I have a lot of experience with the EFI small blocks, the HO or High Output 302's do indeed have a different firing order from the older models. The HO motors which you would find in a mustang or 89 and newer t bird or cougar use the 351 firing order. I'm hoping to find some GT40's to use, but I'm not holding my breath. The only way I might stay carb'd is if I end up with a 351 as performance EFI intakes are expensive and rare, so the 302 is more likely. I will start a build thread as soon as the truck makes it to its new home, its about 300 miles away right now in Minot. Luckily it escaped the flooding, my eclipse however...


That white spot on the seat... is a mushroom!!!

 

I hate to tell you Brain, but Ford bolted an overdrive behind the Fe for many years begining with the first Fe the 332 in 1958. The normal overdrive was the B-W T-85 with an R-11 OD. This was offered in the cars (long tail housing) from 1958 into the mid 60's. and in the F series trucks (W/short tail) from 1965 thru 1971.

The other overdrive Ford offered was the B-W T-86 w/OD that was commonly used behind the inline sixs and the 292/312 V8's.

 

true enough...but like BrainDamage said- you're not going to find one.
The Borg-Warner Overdrive Transmission Explained- FORDification.com

plus...due to the problems that could be caused if you didn't understand the freewheel, wasn't this design outlawed for the most part?