ok I'm getting confused. with all the interchangable parts on a 390 (427,428,360) what would be the best way to build my 390 to 450+ H.P.?
Could, if it would work, bore out the 390 to 429 and use a 428 crank, 429 pistons, and either 428 or 390 rods? If that will work, what cam and heads would I be able to use? I would love to use a 390 tri-power intake. If there is a better and less confusing way to build a horsepower monster please let me know. I believe I have a 390 2BC in 1 truck (1969) and a 360 2BC in my other 1969. Thanks for any help I can get. Jack

 

I'm not really familiar with the 385 series (429 and 460), so I don't know what the bore dimension is on a 429. I can tell you that the Ford spec on a '69 390 is that it will take a maximum of .060 overbore. Some blocks will actually go to .080, but have it sonic checked first. As the stock bore is 4.05", that means that your maximum bore will be around 4.11 - 4.13". It will be easier and cheaper to get pistons for a .060 over than for a .080 over, despite the fact that .080 over gives you the standard bore size of a 406 or 428. Bottom line - don't take it more than .060 over if you don't have to.

390 and 428 rods are identical, so there is no need to decide which to use.

The 428 crankshaft is a good idea. With a 390 crankshaft (3.784" stroke) and a .060 overbore, you'll have about 401 cid. Drop in a 428 crankshaft (3.98" stroke), and you're up to 422 cid. With a 428 crank, by the way, you also need to get a 428 flexplate, because the 428 crank is externally balanced by a weight welded to the plate.

The 428 crankshaft will help you generate some serious torque, but the FEs are not good breathers and they have notoriously weak valvetrains. To get to 450 horsepower and do it reliably, your best bet is to keep the compression ratio high (say, 10 or 10.5:1). If you want to avoid having to run race gas, that means using aluminum heads such as the Edelbrock units. A side benefit is that Edelbrock heads come with the "Cobra Jet" size valves, which are quite a bit larger than standard FE valves and, of course, flow much better.

Finish your engine off with a set of headers and a good aftermarket aluminum intake like the Edelbrock Performer RPM, and light it off with a good electronic ignition. With a moderately hot cam, you should have no trouble hitting 450 horsepower.

 

Karl has some good points. The FE valvetrain is ok with stock parts. Use stiffer springs, and you start pushing your luck. The exhaust ports are restrictive, but the manifolds are terrible!

If I needed a 450 horse FE, here's what I'd do:
I'd start by boring the block only as much as necessary to acheive a good ring seal. By boring as little as possible, you retain much of the cylinder wall strength, and thinner walls have been known to cause hot spots and cooling porblems in some blocks. Use your stock but machined (if necessary)cast crank, resized stock rods, ARP Wave-Loc rod bolts, mabye ARP main bolts or studs, and a good set of forged pistons. Aim for nine or nine and a half to one compression ratio. And get it all balanced. Flywheel and balancer, also.
For the heads, if you've got the dough, splurge for the Edelbrock Performer RPM heads. If you can't afford those, the next best thing(imho) are the C6AE-R heads. Look for these on 1966 352 engines. Essentially the same castings as the 428 CJ heads without the CJ valve sizes. Match the Edelbrock Performer RPM intake manifold to these heads with a good(read "not cheap")set of headers. Add to this a carb of your choice, as long as it's capable of flowing 750cfm.
Next, get on the phone to your favorite cam tech guy, and order some parts. Get a good double roller chain set, like a Cloyes Tru-Roller. You'll also need some good rocker shafts and stands. Look to Ford Power Parts for these. http://www.albanos.com/w/fpp/
Add aftermarket electronic ignition, aftermarket fuel pump and regulator(don't scrimp here), and provide for an adequate cooling system.
What you've built here is a good running engine with a strong bottom end, and a top half that'll breathe! Nothing too exotic, no fancy machining, and good for about 300-350 horse power. But wait! We need another 100 ponies! The engine described above is a perfect candidate for NOS !! Add a NOS Powershot kit for an easy 125hp gain.

Again, just my opinion...

 

So, what if I bored a 390 .060 over, bumped the compression up to about 10.5 to 1 with forged pistons, added a radical cam with about .6 inches of intake lift and about the same exhaust, ported and polished the heads and added oversized valves, upgraded the rest of the valvetrain, bolted on some good headers, and topped the engine off with a dual quad intake sporting two 800 CFM Edelbrock carbs, what kind of ponies would this hoss put out?

 

but then you lose cylinder wall strength and run the risk of hot spots and you will have to run 93 octane at the very least. That radical of a cam will make an absolute dog out of your FE for pulling and low rpm use. The motor you just described is a good high rpm engine. If I were you i would take 390fe's advice, only I would bump it up to around 10:1 compression and spring for the 428crank. Flatlander Racing now offers FE cranks on special order also. For a cam, Crane offers a cam with 216 intake/ 228 exhaust duration .533 intake/ .566 exaust lift, that may be a good cam for what you want, although for towing that may be a little long on duration. Basically what i have just described for you is what i am running in my 71 F250 4x4, but i have a Comp cams Magnum 270 which isn't a good choice for FE's, but it hauls nontheless. I use mine to tow a trailer of quads over the mountains and it does a good job, it would be better with an auto with a 2500 stall, but the 4speed is ok. I have 4.10 rear ends also.

 

I just saw that you didnt mention anything about towing. So yeah, a huge cam and high compression are great for high rpm hp and a dual quad manifold is great. Maybe not 2 800's though.

 

Yeah, 1600 CFMs might be a little much . However, if the engine I mentioned was paired up to a good C6 with the right stall converter and 4.10:1 gears, it should be awesome. I'm not all that familiar with FE's but I might be buying a truck with one in it. So, I plan on building it to be fairly high-performance. I'd rather have a 460 to work with, but, you know, can't have your cake and eat it too.

 

Or read the new Hot Rod where they build a 450 horse 390....

Also I've heard great things about the Comp Cams Magnum 270S in a F250
I run the crane cam mentioned .533/.563 and like it, but it's not a 450 horse cam

 

>Or read the new Hot Rod where they build a 450 horse 390....

The current edition of Hot Rod? I haven't seen it yet
>
>Also I've heard great things about the Comp Cams Magnum 270S
>in a F250
>I run the crane cam mentioned .533/.563 and like it, but
>it's not a 450 horse cam

 

I get Popular Hot Rodding but not Hot Rod. I would love to read that article, though. Anyone want to scan it or tell me where to find it? I plan on buying the truck I mentioned within a week or so. It's a '71 SWB 2wd half-ton with a 390 but no tranny. It had a straight drive but I would like to put a C6 with a manual/auto. valve body in it. Any advice on the transmission upgrades I should use including what brand of valve body to get? Also, will the front grill from a '67 fit the '71? I like the looks of the horizontal barred grill from the '67 better. Thanks, Jake

 

Do I have a deal for you.... I just hapen to have just what you need. I have a trans and converter on Ebay as we speak. Here are the links.Check them out.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1873749315&ssPageName= ADME:B:LC:MT:1


http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1873750291&ssPageName= ADME:B:LC:MT:1

 

That's a steal but I have to do things in steps. You know, buy the truck, wait a month and buy some pistons, wait a month and buy a cam...