Say Hi to the newbie!! (that's me ...in case your wondering...)
I'm getting ready to rebuild a 390 out of a Thunderbird for my Ranger and I'm trying to gather all the info that I can before I dive headlong into the project. I'm trying to workout all the internals for the motor, but having never worked on FE's before its a bit challenging. I'm building the ranger for a weekend car/drag racer. It needs to be streetable, so I'm looking for around 450hp.
Might as well start at the bottom... My friend(who's been around FEs forever) recommended that I track down a 351 Truck crank because its a forged crank and I'll never be able to break it. I'm trying to find one but I think it would help a ton if I know where to look. Do any of you know where I can get this? Or at least which trucks I should be looking at in the junk yard? Any chance that I could find one NOS?
The only other thing I'm mostly certain about are the heads, I'm strongly leaning twards some Edelbrock performer heads, so I can run no lead gas and not worry about it(the motor is from a '62 Tbird FWIW). I'm totally up in the air on the rest.
I'd really like to get one of those Tri Power setups, but I really dont want to spend the $800+ that I've seen them go for, not for an intake anyways. There is a speed shop down the street that has an edelbrock air gap for the FEs that looks really great, and its a heck of a lot lighter than the stock manifold but I dont want to set the intake before I get the rest of the internals sorted.
Any and all help will be greatly appreciated, Thanks!

 

First, the crank you are referring to is a 391 truck crank. It would be found in the BIG trucks, like dump trucks. Second, you probably don't really have to have it if you are staying under 7000rpm. Yes, it would be stronger, but 450HP under 7000rpm doesn't require it. If it were me, I would use the stock crank and put the money in other components, like Erson rocker shafts.

For the build you are describing I think I would use the stock block with the oil mods described in the FAQ, stock crank, either stock or Eagle rods, and a set of forged pistons that will have a compression ratio suited to your cam choice. Either solid lifters, or hydraulic rollers, Ebock heads, and a performer RPM manifold with a 750 or 850 Holley or Demon carb.

450 should be easily attainable with the right cam. You will have to sacrifice slightly on the bottom end performance, but not to a great degree. Also, I would guess that 450 could happen as low as 6000rpm.

-Scouder

 

Ok here we go. Here's what should get you at least 450 hp:

1. You dont need the 391 FT crank, like Scouder said. The regular 390 crank is PLENTY strong.
2. Overbore .030" to clean up the cylinders
3. 1.76" compression height pistons, valve reliefs only no dish - 10:1 compression
4. Edelbrock heads
5. Edelbrock Performer RPM intake
6. 750cfm carb
7. Crane 349521 roller cam
8. Headers and mufflers

DD2k shows 463hp @ 6000rpm, and 471 ft-lbs @ 4500rpm.

 

That looks good to me. It would be a great street engine. It is essentially what Gtex has, but with a shorter stroke.

-Scouder

 

Thanks for your helps guys! I'll look up all this stuff once I get out of work, so thanks for all the reference material! I'll be sure to ask if I'm got more questions.


btw: Why cant I see my sig?

 

Plus the 391 steel crank has a larger snout. Either you need to use a FT timing cover which are cast iron or maching the crank snout which is around $400. As advised your nodular iron 390 crank will do fine. You can always pickup a 428 crank and get a little stroke out of it but piston deck height will require different pistons. The 390/410 stroker kits are fairly common and easy to find pistons for that will work. G.

 

Truck crank because its a forged crank and I'll never be able to break it"

Have you ever heard of ANYONE breaking a crank? Just one of those things that you might want to think about.

 

Why YES, yes I have... The motor that's in my non-Ford daily driver is known for its weaknesses and I know at least two friends that have broken cranks because they put it on the bottle(NO2). and if your thinking well that's a non-Ford so it's obviously weaker, then how's this... a friend of mine, the one who's loved FE's since the beginning, had a buddy that built one of those Cobra kit cars, and he built up a 428 to drop in it. He was continually doing 6000rpm drops and broke at least TWO stock cranks in the process. At some point he found out about the 391 crank, had it turned down and installed. From that point on he never broke the crank.

 

428 cranks have a rather long stroke to begin with. That alone weakens the crank. That, and 6000 rpm's aren't particularly good for ANY motor, let alone one with nearly a 4" stroke spinning at 6000 rpm with a shock load applied.

What particular non-ford engine was it that broke a stock crank? 350, right?

 

Its a 3.3L chrysler V6

 

It is truly uncommon to break an FE bottom end. By their nature they are a strong design. FE cranks can be broken, however, just like any other. If you plan on doing continual 6000rpm drops, like your friend, then I would advise the 391 crank, and do the necessary machining to put it in your block. Your initial post didn't really reflect that kind of usage, so the consensus was that you could save money by using a stock crank. If you are not going to be that agressive, I stand by my statement that a cast crank is more than adequate.

-Scouder

 

Well if your confident in the FE crank and so is basically everyone else, then so am I! Thanks for the info guys. I'll stick with stock.