Howdy fokes I'm just dreaming and doing some research. I got a 73 ford F250 it's got a warmed over 390 build I made for it now. But I've been dreaming of doing a real proper 427 for it now that aluminum aftermarket blocks are more of a thing for FEs 2 things I can't seem to find anything about.
1) how to make these engines make reliable efficient power. 427s were never designed for gas milage and i dont want to change that I just don't want to have a 50 gallon gas tank to make it to town. some of the newer screw type blower/intercoolers look like their real efficient problem is how to make it work.This will be a daily (I'm hoping) so figured I'd jump for fuel injection. Try and keep it in the double digit potential for gas mileage.
2) how do fokes making 700+ hp do for standard transmissions. I have a 3 speed top loader which are supposed to be pretty tough....but not boosted 427 hp tough. Unless running thinner (stock) size tires act like the weak link saveing the transmission which I'm ok with this won't be a 1/4 mile racer just a fun *** old truck. Thanks for reading this fokes looking forward to some good advice.

 

You have a couple of questions here. I have had numerous 427 and 428 engines. We now have a 511 ci. aluminum pond block. If you want a 700 plus hp FE, then you will be at 12:1 or better compression. 110 to 116 octane fuel. Not realistic as a street driver. Our C6 transmission is highly modified for our engine. Your axles will need to be 35 spline or better to live with 700 plus hp. The heavier the vehicle the more carnage you have as you get to these hp levels. Forget good fuel mileage even with fuel injection. Sorry for the negative response, but I have " been there, done that".
A good alternative project is a stroked 390ci into a 445ci. 530 usable hp is possible for a lot less money. 12 mpg is possible. Unless you have an extra 25k to spend, I would go with the 445ci.
JMHO

 

Honestly after you invest 15k in the engine you won't want to daily drive it. At that point they are fun powerhouses but not reliable in that HP for more than 25k miles as I have found.

 

Since you're considering aftermarket blocks, might consider a cast iron. The aluminums do okay but cost more and can be a little more difficult to build. Some of the aftermarkets blocks can be bored to 4.440" and stroked to 4.375 for well over 500 cubes. A common displacement is 482 because 4.25 stroke fits easily and 4.25 bore leaves you plenty of meat left in the bores. The trick is being at the right place and time to get your hands on a block. Some of the newer aftermarket aluminum heads come out of the box making good power and do better with massaging.

Sounds like you're considering a blower which I can't help with. But if you stay with N/A and 482 cubes I'd think 550 hp can be had reliable out to 100,000 miles....for around $15-16K. Understand, this will come with 600 or so honest to goodness lb/ft at a daily driver rpm range so you will feel it even during mild launches. Depending on your gears I believe you can get 11-12 mpg on the freeway though a heavy foot quickly drops the mpg. For reliability the main thing is get with an experience builder. Even if you want to do the assemble yourself, having the experience to consult on parts combinations will be a big help.

Lot of guys go with a TKO tranny to handle the power. I currently have a NP435 and am considering adding a gear vendor overdrive to my F250. I sometimes tow 10K lbs. My FE is just north of 500 hp and 600 lb ft. If you plan to have locking differentials and drop the hammer a lot might go with beefier axles as was already recommended.

 

Changing the subject a little bit, I consider any FE a toy not a daily work horse. If you want a pickup to pull a trailer or fifth wheel then buy a newer F250 or F350 Power Stroke Diesel. Our 2012 F250 PSD gets 22 mpg average empty and 13.8 mpg pulling our 5th wheel along with 400 hp and 800 torque. Even our 511 ci. FE only has 713 ft.lbs. torque.

 

That is an interesting theoretical debate. There are times when I think if I could buy my '65 F250 brand new today with the motor it has now I might do it. I think I'd want a bigger fuel tank, an overdrive and maybe power disk brakes on the front. I actually prefer some of the features on this truck over today's brand new trucks. My current "new" truck is a 2002 diesel. I like it a lot but if something happened to it I might find a crew cab from the '70s or '80's to drop my FE into for pulling our fiver with the family. This motor pulls very nicely with authority, can diagnose and fix fuel or ignition issues on the side of the road, etc. I guess if I had a business that relied on a truck and kept me too busy to do my own wrenching then I'd lean toward a brand new truck. For my situation, I'm very happy with my FE and would drive it across the US, up to Alaska, and back again.

Diesel has it on fuel economy though I'm not so sure on overall costs. Price of admission, maintenance, and eventual repairs is pretty steep on a modern diesel.

I have considered losing the fiver and getting a Class C but that's a whole 'nother story.

 

Yohon, I've looked back at your earlier posts and at the type of towing and hauling you have planned. A 390 turned into a 445 would be plenty. A 427 stroker would just be added fun. :-) In fact, done right it would have as much or more torque where you'd want it than all factory built pickup truck engines except for the current 6.7 diesel.

For towing/hauling probably want your torque peak around 3000 rpms. If going with a stroker motor you about have to consult someone with lots of FE experience to help choose a cam to get the torque peak at the right rpm.

 

Not sure how you figured this. I've got a 99 SD F250 with a 330,000 mile 7.3 backed by a 6 speed and 3.73 rear and it's been turned up for the past 5 years (and more by the PO) It gets 19 mpg, pulls anything you can hook to the bumper. Want to pass another vehicle ? Just mash the gas and wait a second or two for the turbo to spool up, then you're off ! Don't even need to downshift outta 6th. I bought it with 256K on the clock 6 years ago and so far have only changed the fuel pumps and water pump. I paid $5000 for this truck. Spent $1500 on the pumps since then. I change the oil once a year regardless of mileage put on it. It still runs like new. You'll never get that out of an FE.

 

The diesel mentioned was a 6.7. I'm thinking it'd take quite a few miles ...over 100,000... for the OP to justify the cost of going that route. I expect a properly built FE to go 100,000 miles and maybe 150,000 before needing a refresh. There are benefits to the simplicity of the FE and it will make enough power for a pickup. Don't get me wrong, I really, really like my 2002 diesel but for the way I use it the economics don't strongly favor it. Also power-wise, my FE will beat my stock tuned diesel.

There's a place for diesel, though I really don't think it's a good fit for the OP's scenario. I agreed with Maxtor I'd go new diesel if the job required it. The OP was asking about building a reliable FE and what gear boxes to put behind it.

 

700 hp and reliability in an FE for 300,000 miles just ain't gonna happen. The 7.3 may not make 700 hp, but the torque output where it's needed is twice what an FE will do. And the OP is talking about older trucks. He'd be better off transplanting a 7.3 into his truck.

 

The 7.3 diesel is a very good engine, although Ford hit a home run with the 6.7
I am not sure what a good used 2011 F250 or F350 with the 6.7 would cost, but I am sure the smiles would make up for any extra costs. The torque is unbelievable. I know the 2019's are at 900 plus, ft. lbs. torque, but 800 is plenty.
All I was pointing out is that for a daily hauler pickup, you are hard pressed to beat the 6.7 which again has more power and better fuel economy than our beloved FE's
We all have favorites, mine is the 1972-74 F250. with a 428 or 445. Again this would "for me" be a toy, not a work truck. Add to that the comfort, of the newer trucks, and it is a win, win, situation. Power, mpg, comfort, style, Ford got it right again.

 

My FE peaks at over 500 hp and over 600 lb ft. The dyno operator pulled the motor down to 2500rpm and made over 580 lb ft. To me, that's where it's needed in a gasser. That'd be a good 7.3 to make over 1100 lb ft...and able to live a long life.

I didn't see anyone else (including the OP) mention a mileage requirement...I kinda doubt 300,000 miles is necessary. I also kinda doubt the OP is going to use a '73 pickup for regularly towing modern diesel truck type loads.

I really didn't expect this thread to turn into a gas vs diesel debate. The OP asks about building an FE in the FE forum and is told to get a diesel ?

 

The 7.3 makes it's torque below 2500. My 7.3's cruising rpm is that at 70-75. He was pointed towards the diesels because of the power figures he was quoting. I quoted 300K as an example of how long they last vs an FE.

 

Just at a glance the prices for these are still way up there for what I would pay for a used truck that old. But that's me. Also hard to finance an 8-10 year old vehicle in that price range, which is more than most people would have laying around to pay cash for one. I'm with you though on a FE pickup being more of a toy than a daily driver. Loved my old 70 F100 with its GT390 I had in the 80's. I also think the OP would do better stroking that FE to a 445.

 

Boy thanks for the quick and through response guys. That was what I needed to hear. I don't need a 800hp fire spewing ford. I just want the oltruck I grew up on. I still like the idea of a new 427 block. Just the fact I can make one all aluminum appeals to me plus the oiling set up and cross bolted mains don't hurt either. The blower and all that got dreamed up to "save gas". A naturally asperated stroker would put me at 500 pretty easy even on a conservative tune and pump gas. Which in all honesty is more then the rest of the truck could handle. I got my dad's old 24v Cummins for long hauls and stupid amounts of power (more boost more fuel&#128520. What would y'all recommend for stroke and bore on a N/a set up like that though? Longest stroke with narrow bores? Or should I step up bore and stroke together? Thanks again fokes