I have a 1974 F100, 4WD, short bed, with a 1978 400 engine (which is tired, and I'd rather not rebuild). A neighbor is willing to sell me his 390 in a 1973 Ford F250, which I would be interested in having rebuilt since I've read is a superior engine. It hasn't run in 15 years, but he states it ran fine up to that point (130K miles). I would pull it, and take to Phoenix Engine, who can do high performance rebuilds.

I am seeking advice on what price I should offer him? applicability to my truck? and any other insights?

Thanks,
Eric in Chino Valley, AZ

 

What transmission do you have?

"High performance" rebuild? How high?

IMO you are in for a rebuild of sorts with that 390 anyway, so why not rebuild the 400 and not have to deal with bell housing or auto trans issues? Plus mounts, exhaust, front of engine accessories, etc?

But then your truck came with an FE in the first place, so maybe you have all that stuff already?

 

As much as I like 390s, had one in a 68 Galaxie and loved it, I would just save your pennies and rebuild the 400. Be wary that the guy "says" what he thinks is a 390 could be a 360 as, to my knowledge, there is no way to tell from the exterior which is which. I would check block numbers and VINs to verify and even then that is a gamble. 85e brings up an excellent point with swap components.

 

I love the FE blocks, my pops has a '66 Fairlane GT 390 4-spd convert it is a snotty engine. Stock 335hp now somewhere in the 400hp range, but a truck motor starts out around 180hp. If you are looking for H.P. the truck 390 is a low compression torque motor, would need pretty much everything to make a hi-po motor from this. They are like 7.5 or 8-to-1 compression motors, not like the Fairlane, Galaxie & Thunderbird HiPo 9.5-to-1 motors. Although the rumor is that the truck block has more webbing and is a little stronger. The 390 has a lot of nice power adders especially if you can find some Holman-Moody intakes, however be prepared to crack open the check book.

 

Agree just rebuild the 400 assuming you have a reputable shop you can trust. As far as offering a price to them, usually its the other way around. An engine rebuild can go from very basic to very complex depending on what all you want to do and cost can vary greatly. You need to sit down with the builder so they can explain the options and decide what all you want to do. It really helps to do your homework on the specific engine build ahead of time which will help you understand better as you discuss options with the builder. Don't assume anything and get it in writing and don't pay for work that has not been done. OK to pay up front for parts but shops will sometimes ask for money down to cover labor before they actually do it and then your engine sits in the corner collecting dust for weeks. Also keep in mind the more towards performance end the build goes the more risk of nuisance problems in normal street driving.
As for the 390 - yea we seem to hear that statement a lot "ran good when parked" LOL

 

The 390 and 400 can both make good power. I would just do a 460 though. Probably money ahead in the end, and less oil leaks in the driveway. I'm in Chino Valley also...

PM sent.

Edit: I have a 460....

 

since your rig came with an FE it's hard to say why someone went to so much trouble to put a piece of crap engine in it.

Your easiest and cheapest option would be to rebuild the POS engine you have. your best option would be to put a 385 series engine in it but that's going to require more parts and more money. your ultimate option would be to put it back to original with an FE but that's going to require everything from the fan to the drive shaft. basically you'd need a parts rig to rob.

 

Everyone always forgets this question...

What's your expectations for cost? What sort of funds do you have available for a rebuild? Do you have 5K? 10K? What sort of numbers/budget are we talking here?

Cost matters.

 

If you're going to buy the engine off the guy, just try to get the whole truck. You'll probably need the parts anyway.


If it is a 390, and hasn't ran in years it's still not worth much. Check the valve cover for the emissions sticker. They say "engine family 360 390" and everyone gets all excited and think they have a 390. Then, right below that it says "engine displacement". That's where most of them say 360.

If it is in fact a 390, and you're going full rebuild, you're going to buy new pistons anyway. Just get higher compression pistons. Poor compression problem solved.

If it's a 360, theres no feasible way to get your compression up. Better off getting a 390 crank and rods.