Engines

[buffs 78 ford]

Hey new here. My name is Tom and I bleed ford blue. Anyways I am Starting a new build my 390 in the ford is getting lazy. Its already been bored .040 with c6ae rods full floating wristpins. Head have hardened seat but the valve guides have been nurled with oversized valves so this engine wont be used again to much money to fix. I found a 391 industrial for $150, So can I use the steel crank with my lamans rods, my 390 passenger car heads and a thumper cam and it hold together. I know the stock 3 ring 391 pistons wont hold up. Any hints. I have two sets of the good rods both are floating pins.

[Ranger429]

Welcome to the forum, glad to have ya. I know absolutely nothing about the 390 motors but I'm sure someone will come along. Post some pics of the truck.

[buffs 78 ford]

Not a real good one wife deleted the good ones

[Ranger429]

Stepside, nice. What year is it?

[buffs 78 ford]

Trucks a 78 bed is a 85.

[Johnny]

As far as I can tell the only differences were the crankshafts... the harmonic balancers, and flywheels..

The FT has a larger diameter snout (The FE snout is 1.38 inches, and the FT is 1.76 inches).. and a thicker flywheel flange... Plus the FT is externally balanced like the 410 and 428's....

They both used the same rods.... the long rods (6.540 inches) and the short rods(6.488 inches).... Long rods were in the 332, 352, 360, and 361 FE engines, and the 330 FT engines... all the others (FE & FT) had the short rods..

Who knows if the 390 piston and a set of lamans rods will fit the 391?

Yes sir you can... you just have to have the 391 crank snout cut down to 1.38 inches by a machine shop.. oh, and the flywheel flange cut down as well....

and both were a 4.052 bore, and use the 3.784 throw crank, so your good there...

Not really sure about the balancing as the FT's were externally balanced, and "most" of the FE's were internally balanced... I'd ask the machine shop that one...

[buffs 78 ford]

I was hoping to use the 391 block, crank, flywheel etc. And use my good 390 rods, pistons and heads. The 391 I found is complete with flywheel.

[Johnny]

I'd say your good to go then... keep it externally balanced

[buffs 78 ford]

Dont know how I ended up posting this same question in both threads. I will have extra 390 parts. I have 4 heads 2 car 2 truck 1 car intake 1 truck intake with egr set up. balancers, 4x4 oil pan dont know what there worth but they will be for sale. I also have a 351 windsor, a 95 5 speed and transfer case I will not be using

[Johnny]

Damn you sound like me... I've got two 428's, a 390, a 352, a 410, two 302's, a 289, and a 300 six... the last three are for sale as well... not to mention the two top loader 4 speeds, a top loader 3 speed, a C6, two AOD's , an E4OD and two three speeds out of early Bronco's.. man this stuff multiplys quick...

[buffs 78 ford]

I would love to get a c 6 for a 390. 2 or 4 wheel drive I can change it to a short output shaft

[Johnny]

I don't know where any are right off.... but I'll keep a look out for you...

[Salt-Man]

Buff where are you located at? I am in upstate NY by Niagara Falls, I have a real sweet 390 with a c-6 and a divorced np205 transfer case that I may be willing to part with come spring time when I can get it pulled
http://i196.photobucket.com/albums/aa208/rsalter66/bronco285.jpg

Minus carburetor, let me know, hell I might even sell ya the the whole damn truck
its a 76 F250 Hi-Boy 4x4, its all there except some body parts and wheels and interior
I used it as a parts truck, but the drive train is all intact..Rick (Salt-Man) ?><L>?

[buffs 78 ford]

I am about 7+ hours from you but keep me posted please.

[Salt-Man]

if you decide that it might be something you want to make a road trip for let me know, I wont be doing anything until spring, I was going to put the axles in my bronco but I dont think I will, I think the bronco is going to be a street ride now
bring a trailer and take the whole thing, trade me something cool or throw me some cash for it
I am buying a 79 Chevy 4x4 to beat on so now I'm going to keep the bronco for something nice and put the hard top back on

[Gilligan]

I built an FT hybrid that is in a '74 F-250. I kept the FT block and crank and used 390 pistons in it in pace of the 4-ring industrial pistons. The pickup 360/390 flywheel required a LOT of weight added (welded) to it to bring the balance in spec and IIRC, the crank had to be machined to accept the 'small FE' flywheel. I also had to machine my own pilot bearing out of oilite bronze..there are no 'off the shelf' oens that fit the large-bore FT crank with the small pilot bore diameter.

Water pumps are getting hard to find for the FTs..and so are the engine gasket sets..and both are pricey when you do find 'em. Note also that if plan on keeping the FT heads, then you have to keep the FT intake..the FTs have an exry large exhaust cross-over that is not same as FEs. Me, I slapped a spare set of 428 heads and a cast iron 428 intake on with 'em and called it good..but of course lost those fancy stellite FT valves in doing so.

Were I to do one again (the last one I built was at least 10-11 years ago and more FT parts were still available over the counter then) , I would simply have the steel FT crank snout and flywheel end re-machined to fit an FE and go from there.

Oh..and the FE dizzy won't fit an FT either...but I made a Duraspark one for mine using the FT original and the plate and stuff from an FE dizzy.

[buffs 78 ford]

Thanks for the info, thinking twice now about it. I have a crank thats got the 390 part numbers on it but with it in the block the stroke is 3.89 I have no clue unless some one had it offset ground. It had a set of c6ae rods and 360 flat top pistons in it. The engine was wicked. The pistons came to the top of the deck on tdc my other 390 only came about less than a 1/4 inch from the top. by the math the engine was about 399 cid. That one may go back together

[Gilligan]

Thanks for the info, thinking twice now about it. I have a crank thats got the 390 part numbers on it but with it in the block the stroke is 3.89 I have no clue unless some one had it offset ground. It had a set of c6ae rods and 360 flat top pistons in it. The engine was wicked. The pistons came to the top of the deck on tdc my other 390 only came about less than a 1/4 inch from the top. by the math the engine was about 399 cid. That one may go back together


Put a mike on the journal of that 3.89 crank. That would be well within the realm of possiblity for an offset grind on a 3.78 390 crank..the journal OD will tell the rest of the story.

[buffs 78 ford]

who came up with using 360 pistons in a 390 I know there the same bore but the piston pin hight is just abit different.

[RTM]

Dont know how I ended up posting this same question in both threads. I will have extra 390 parts. I have 4 heads 2 car 2 truck 1 car intake 1 truck intake with egr set up. balancers, 4x4 oil pan dont know what there worth but they will be for sale. I also have a 351 windsor, a 95 5 speed and transfer case I will not be using

What's the 5 speed out of?

[buffs 78 ford]

94 f 150 4x4 tranfercase is for the bolt on drive shaft not a slip yoke

[buffs 78 ford]

Got the 391 in a trade and forgot about a 1978 2 wheel drive that a friend gave me. Yea parts truck. Bought a 90 model festiva off a guy that broke down the other day at the dealership 100 bucks traded it for the 391.