331 or 390

Hey im going to put a 390fe in my f100 but i really want to builld a 331 stroker really really bad. im still going to run the 390fe but which sounds better to you.


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A 331 is gonna cost you twice as much and still be 60 cubic inches smaller... IMO a 331 is a bit on the small side for a pickup.

What do you have a drivetrain for?

Unless your racing in a class restricted by cubic inches there is no reason to destroke a engine for less cubic inches. the 390 will eat a 331 hands down.
Why spend more money on less cubic inches and less power?

which ever u decide to build i wouldn't build it really really bad i'd try to do it really really good

You can get more than enough power out of a 331 but i would start from a 302 block. The 390 was the red headed step child of the ford motors. They were never really known for making big numbers when it came to making horsepower, It was always a odd ball motor. I would go with the 331 or even a 347. if you do a 347 make sure you dont get the 5.4 rods, get the 5.315 rods, it takes the pin out of the oil ring

Member"Tech Inspector" just did a DynoSim build on a 390 on another website utilizing a Crower 16255 Cam,pm him about it, the figures will CHANGE your mind about FE blocks,just a hint, over 520+ foot pounds of torque! ODD BALL Motor?

The 390 was never a odd ball engine, this engine powered everything from cars to pickups to dump trucks to boats and irrigation pumps. If any of the FE's engine were ever considered odd ball it would be the lowly 332 or 410 Merc, due to short production run.

390, with a small amount of encouragement these things will pump 400 horses and 400 foot pounds all day long.

There's folks that put down the 401 horse, 3 duce, 390 of 1961/62 as being over rated. But then ask how many ever came up against one. If you weren't packing a dual quad 409 or a Ram Charger 413, you were toast.

Speed Channel did a shoot out of some of the 60's muscle cars. In the quarter the fastest in order were:
1) 454 SS Chevelle, suffered from having a 3 speed auto, would have been even faster with a 4 speed stick.

2) 428 FE block SCJ Mustang. Suffered from rear spring wrap up even with bars, would have been faster if you could plant the rear tires better than it did.

Everybody else gets in line. That's not to say the other guys were running inferior engines as there's plenty of mighty good hardware from the era, but you gotta get it hooked up to win. But between the front and back of the pack the separation is in hundredths of a second. It isn't like any of these things were in reverse compared to any other.

But the point I'm trying to get to is the FE is a plenty good place to start a build with a FoMoCo.

Bogie

Thanks Jeff, I'll just post it up here for all to see. Jeff picked the cam for this one after I went through 6 Comp grinds.
I'm retired and enjoy putting together combinations on my playtoy, DynoSim version 4.20 software. I'm no different from most of the other motorheads on this forum, having wrenched on hot rods for 50 years, doing most everything from stock rebuilds to drag race motors, front end/rear end rebuilding to clip swaps, frame swaps and engine swaps (my favorite). Anyway, I'm 67 now and can't do many of the things (physically) that I used to be able to do, so I placate myself with this playtoy and passing on stuff from my noggin to others who can use it to their advantage. Many, many knowledgeable people have helped me in the past, so I feel a responsibility to help others with what I have learned.

I have built only a couple of these FE motors in the past, so I don't have all the detail knowledge that others have, but in the end it's just another air pump and so will respond to the usual changes in my opinion.

390 block bored +0.030".
390 crank
Rods: I'll leave this to others who have more knowledge of the FE
Pistons: Speed Pro L2291F30 forged.
http://store.summitracing.com/partde...0&autoview=sku
Heads: Edelbrock 60069, 170cc intake runners, 72cc chambers, 2.09" intake, 1.66" exhaust.
http://store.summitracing.com/partde...5&autoview=sku
Static compression ratio: 9.9:1 with this piston and head.
Intake: Dual-plane, high-rise such as the Performer RPM or Weiand Stealth.
Carb: 850 CFM, double pumper if using an automatic with 3000 or better stall or using a stick shift trans. Otherwise, use a carb with vacuum secondaries.
Headers: large primaries, equal-length, long-tube. (real headers, not those cheezy shortie units).
Cam: Crower 16255 hydraulic flat tappet, 280/288 degrees advertised, 224/232 degrees @ 0.050", Intake Centerline 104 degrees ATDC, Exhaust Centerline 112 degrees BTDC, Lobe Separation Angle (Lobe Center) 108. Theoretical valve lift with stock rocker ratio, intake 0.549", exhaust 0.560". Overlap 12 degrees @ 0.050". Timing events are: Intake opens 8 degrees BTDC, closes 36 ABDC, Exhaust opens 48 BBDC, closes 4 ATDC. Dynamic compression ratio with this cam and 9.9 static compression ratio is 8.647:1.

This cam clicks off at 5600, but makes excellent torque down low, which would be great for a heavy vehicle or tall gear or both.

RPM HP TQ
2000 170 446
2500 214 449
3000 273 477
3500 337 506
4000 399 524
4500 449 524
5000 491 516
5500 505 483
6000 457 395
6500 404 326

Juggle the block deck height and gasket thickness to achieve a squish of 0.035" to 0.045". With a tight squish and optimized ignition timing, this motor should easily run on pump gas with zero detonation.

There are many who poo-poo the results of these software dyno pulls and in some cases I have to agree with them that the numbers are optimistic. The beauty of the software is that you can COMPARE different parts and how they react with each other. It's not necessarily the definitive number, but the comparison that makes the software valuable. I tried 6 different cams (before Jeff suggested the winning Crower grind), advancing and retarding them, 3 different intakes, 2 different pistons, 3 different carbs and 4 different static compression ratios to get the results shown here.

By the way, here are the numbers published by Edelbrock on these particular heads.....
0.100 88 64
0.200 153 113
0.300 195 148
0.400 233 171
0.500 265 183
0.600 270 200

I have a mild 390 in my pickup and it'll light up the rear tires with no problem. I would save the 331 for a mustang, maverick or some kind of light car