I'm slowly getting an accurate picture of the engine in my 74 F100.

It is a 390 with a Performer intake and cam. I'm trying to get the info in Engine Analyzer and there are no sample intakes for FE motors.

How long are the intake runners, approximately, on an FE? The same program shows 4.5 inches for a Performer intake for a small block. Going by that I'd think the FE would be more like 8 inches, but rough estimates with a tape measure shows around 13 inches.

 

Besides the intake and cam and I assume a carb, any other mods?

You know it's a 390 because:

a) you've measure the stroke
b) you were told by the previous owner it's a 390
c) it had a 390 sticker on the air cleaner

I can't find anything about runner length with a 10 min search.

Intake talk with links to books on Ford manifolds and engine building:

https://www.ford-trucks.com/forums/1...paro-book.html

What are you trying to figure out?

 

Previous owner wants to be a gearhead, but he is really, really NOT a car guy. It had a 360 when he bought it but slung a rod. He got a buddy of his that builds hotrods for a living to build a 390 to put in its place.

As it was when I got it, Ford 390 .060 over, Edel 650, Performer 390 intake, Performer Plus camshaft, C8AE-H heads, 1 3/4ish Hooker Supercomps, full dual 2.5, some sort of Flowmaster muffler, but no Flowmaster drone.

I can't get a definite answer on the condition of the heads and what compression ratio he had it built with. He tells me it had the big 427 heads that had been worked on it, which as I understand the intake valve won't open with the smaller bore FE motors, those were milled, ran hot and cracked. He said the heads on it now were untouched, then later told me that I'd love them, they'd been ported.

The engine was built for a blower, but he milled the heads for high compression, but it has super low compression pistons in it so he could put a blower on it, but it has to run 93 octane to keep pinging down... the stories don't add up. The only thing he has been consistent on was the 360 threw a rod and he replaced it with a 390 that his buddy built. I'm fairly confident it is a 390 as the torque is leaps and bounds more than a Chevy 350.

I know he's not BS'ing me about the truck, he really doesn't know. He practically gave me the truck.

I've got Engine Analyzer 3.9, pretty accurate if you put in the correct information. One variable that I don't have is the intake runner length. The difference between a 5 inch intake runner and a 12 inch is about +25lbs of torque and -20hp.

 

I don't know FE heads but if you google "c8ae-h heads" you will find multiple hits here and get the specs. Combustion chambers were 68-71 cc, valves 2.02/1.55.

https://www.ford-trucks.com/forums/9...ead-specs.html

From what I find, these heads are very similar to the D2TE heads as found on the last of the FE motors in pickups. With a sunken piston, compression would be in the 8s.

Unless he put forged "blower pistons" in it, I would not trust the stock cast pistons to hold up to a supercharger.

Overall it sounds like an ok combination of parts if it was otherwise assembled properly.

ymmv, stand by for other probably more informed opinions.

 

You are correct on the casting, I got them in the wrong order.

I've got no intention of going with a blower or anything. Just trying to find out what I've got.

 

Maybe someone will do the desktop dyno for you.

My WAG:

Stock horsepower was around 200 net, give or take. I can't find anything "official" to post a link to. Torque in the mid 300s +/-.

You really can't add the claimed power increase for each component and get anything better than a WAG, so:

Headers are probably worth 20-30 horse, the cam about the same, manifold and carb a bit less. So that brings you into the mid to high 200s for horsepower and probably bumps your torque closer to 400s.

Read the reply number 6 by Barry R here and remember he's probably got 9ish or better compression and aftermarket heads:

390

 

I've got my own dyno program that is pretty accurate given the correct information. I've got just about everything but the intake runner length. If the runner is 7 inches then I have 400lbs at 3500 and 292hp at 4000. If the runners are 13 inches, which is my rough estimate, then it is 426lbs @3000 and 270ish @4000. It feels more like the long runner combo.

 

Figure the difference there being the short runner would be a single plane vs. the longer a dual plane.

Dual plane better for low end torque, single better for top end horsepower.

I think you are pretty close with your estimates.

 

Thanks.

I'm very familiar with small blocks, the FE are a different beast entirely. Even more different than sbf vs sbc. I'm a little disappointed in the Edelbrock FE intake. The sbf performer intake is a sizable upgrade over stock. The FE intake is just weight savings over the stock 4bbl.

 

I saw something in HRM about comparing an FE to a SBC, especially a 390 to a 383 stroker SBC. Of course, since I have neither and no plans, I didn't read much further. You could compare those just for S & G, as the bore and stroke are close, the cubes are close, what about ports, valve sizes, cam, etc? Simply an exercise I suppose.....

"The FE intake is just weight savings over the stock 4bbl."

May be, but FE intakes were reasonably good, and FE heads reasonably good also. Exhaust manifolds--now that's where the FE places close to the top for "worst ever".

 

The FE heads are pretty decent, but the intake could use some work. Compared to the stock parts on the small blocks these are some well breathing engines. Ford engineers are strange lot, and that is coming from a Ford guy. I guess theFE and small block parts were probably developed by entirely different groups.

You'd think those guys would accidentally learn something from the other designs though.

 

One enduring mystery is why so many bell patterns? AFAIK, no Ford bell pattern is "inadequate" so why redesign things dozens of times.....

 

No kidding.

There are at least 5 different V8 bellhousings. They must love to reinvent the wheel every decade or so.

 

If your Performer ports looked anything like mine do yourself a favor and square them up . Mine were a casting mess