My engine searches is over. I entered an agreement to trade some early '80s Ford truck parts for "Steve's Beast" (an id name for a FTE member-supporter) used 360 engine. The engine runs but is in need to be rebuilt. The engine can be rebuilt as a 360, 390 or somewhere above 400. Anything above 400 is truly to much for the truck, I and my wallet (fuel consumption/prices). So I am totally open to rebuild it as a 360 or 390.

About the recipient truck, currently has a 330 HD, is a regular cab 1979 F350 one ton dually. Truck has a steel 15' long x 8' wide flatbed. Truck is on-road transportation. Empty most of the times. Not driven in winter. Cruise-nights, car shows and parts hauler.

Pics of the truck can be seen via the link in my signature. I'd appreciate your opinions or if anyone has been in a similiar cross-road.

Tyl

 

Just my preference - I build the 360 into a stout 390. The difference is the rotating assembly (crank, rods, pistons ). I'd get a 390 crank/rods and 360 pistons. The 360 pistons are a bit higher and will give the 390 higher comp. ratio. A header will add a few more HP. There are a few other things I'd add like an RV cam and a "plastic" 1" carb spacer if you've got a 4bbl carb. Less $$ - noticeable boost in power. I'd also bore it 0.030 to clean the bore and a slight more HP. The FE/FT blocks will go to 0.060 but that is a bit Xtreme.

 

Since they make roller cam gear for the FE and since a 360 will get better gas mileage than a 390, how about a roller cam 360? That ought to give you better gas mileage than a 390 but with low-end grunt like the 390.

 

The 360 will get better MPG only if compression and combustion chambering is brought up to 390 specs or better. 360s have low compression and the piston does not come all the way up in the bore. 390s usually have higher compression and the piston is all the way up in the bore.

Since either engine will be a gashog roller or not, use the 390 parts and enjoy the power.

 

definetly go the 390 route, 360 pistons are the same as 4v 390, crank has extra .280 stroke for more torque, 360's are hard on gas, pistons are over .100 away from the deck so there is no quench, 390's have a better connecting rod as well, don't try to use the 360 rod with the 390 crank, the pistons will hit the head

 

Usually, I won't engage in an argument like this, but this time I can't resist.

It's just flat wrong to say that a 360 won't get better gas mileage than a 390. I'm a little surprised that you would attempt to make this claim. Pumping losses alone will improve gas mileage, let alone the reduced friction of a shorter stroke.

If the pistons are zero-decked, and if compression is held as high as is practical using low octane fuel, part throttle torque will be better with a smaller engine. If the OP used the typical D4 heads, and maximizes quench/squish, the 360 would be an outstanding engine.

A roller cam increases the breadth of the torque band, especially if the LSA is 112 or more.

Considering the high price of gas, it makes sense to consider efficiency when rebuilding. Instead of 'investing' in a 390 crank, investigate a roller cam setup.

 

Put the ol NUhaul under the knife and put a real 390 engine in there. Let it spend the twilight of it's live it's life kicking up it's heels after the life struggle of that crappy engine that was stuffed in.

Paul, you are talking about building an engine not comparing an original 360 to a 390. The 360 was the last FE engine in the series. It was an early attempt to deal with the emissions that the government was forcing on the auto industry. The 360 at best is a de-tuned 390, using a 390 block with a 352 rotating assembly. The 390 got it's rep because it was a good combo design. It always got better gas mileage than the rest of the FEs. The 360s were gas hogs, as was the M that replaced it in 77.

Full grown big strapping men still go goo goo over a 427, but a 460 can make much more power. The modified 351Ws used in NASCAR are making 900hp NA. Times change, things get better, but a 360 was nor is a better engine than a 390. IMHO

John

 

The 390, with it's slightly longer stroke than the 360, increases the power output especially at low RPMs, by a larger factor than the extra cubes would indicate.

The slightly longer stroke increases the acceleration of the piston at the top of the intake stroke. This helps pull air/fuel in especially at low RPMs. At least, theoretically.

And, the longer stroke does more in terms of leverage compared to the 360. A 360 bored out enough to make another 30 cubes without changing the stroke wouldn't put out the torque of a 390.

Not a huge difference, but it's there.

So, when it comes to MPGs, you MIGHT see a VERY SMALL decrease in MPGs comparing a 360 to a 390. Everything being equal - compression especially, as well as the cam.

You also might see the 360 gets WORSE MPGs than the 390, because of the shorter stroke having to push harder to keep the truck moving at highway speeds.

 

The 360 is indeed hamperd by low compression. I'm replacing the 160,000 mile 360 in my 76 F150 2wd, but rather than going the 390 route I have a fresh 352 to install. With a mild cam, 600 4bbl, headders, and respectable compression I think it should work well, not as powerfull as a 390 but OK for what my needs are.

 

Comparing a 360 to a 390 in a truck is the same as doing a 302 to a 351W. The larger engine will get as good, if not better mileage due to it not having to be "worked" as hard to accellerate the truck. Fewer cubic inches doesn't always equate to more miles per gallon. My 95 E150 van with a 351W/E4OD/3.55 rear got as good mileage as a freinds 93 E150 with a 302/AOD/3.08 rear. But the 95 would run rings around the 93.

 

Hey guys;

I just cannot resist just this once.

I've watched this "what engine do I build, or what parts do I install" argument for 45 years. Now I'm talking FE pieces and parts here, and every one of these come down to "how much fuel will I save". And this is where the train comes off the track IMHO.

Here is my theory and as Russ and some of the other older heads know, it is just ramblings of an old man. But pay attention cause their might be just a grain of truth involved.

It does not have a damned thing to do with saving gas now does it? Cause you will never in your lifetime save enough gas to PAY for the parts you will install in ANY FE engine ever built. It just doesn't work that way. FEs do not get mileage, they get gallons to the mile.

So here are the real issues if you will be honest with yourself first.

What are the real reasons you want to build or add parts?

In every truck or car or bike I've ever built or helped build, (see Scouders build) I want it to look good, sound MEAN do flame burnouts just looking at it, and make my guts rumble when I sit in it and hammer the throttle. I mean by the time I get from the Frontier cafe to the radio station I have to get out and take a dump it is so bad and so cool.
When I go down the street I want to look cool and sound like the Devils come to town and all the girls look at this and the guys, EAT YOUR FU@#%#&#ng HEARTS OUT.

nOW HAVING SAID THAT.

Build your truck to do what you want it to do in the end, no holds barred. Don't scrimp cause if you do, you are going to keep building and changing and starting over until you do what I said in the first place. Why do you think these guys hang around this forum in the first place, they are still chasing the rainbow and building and getting ideas from one another about how to build it bigger and better. (BIGGER AND BETTER)
You are trying to decide between a 360 and a 390 tells me you already answered your own question, build a 511.

Just kidding but not so far off either.

Make it do what you want it to do in the end, MAKE POWER, look good and be the funnest truck you ever had. Forget about this MPG crap if you are running an FE because as I said in the first part you will not get better then 15 or 16 MPG no matter what you build and why keep chasing the rainbow. Build it and enjoy it and forget the mileage savings which are the real myth.

Last but not least with every youngster that has asked the same question you did, who was for any reason convinced to build the 360, THEY HATED THAT SUCKER and eventually went back and built bigger and better.

Merry Christmas all.

UncleFudd

 

I LIKE your way of thinking! you are exactly right, but where does it end? I thought 528 would be enuff, o-noooo! now with 22lbs of boost I can't keep the rest of the drivetrain together, melting trannies, so what am I doing? more cubes, figured while it was all out I would drop in my 648 and try the turbo on it, we'll see!

 

i agree that if the pistons are zero decked thermal efficency will increase, but still won't equal that of a similar 390, as is, a 360 is comparable to the chrysler big blocks of the era , ever driven a 400 pentastar powered anything? with 4.10 gears those things were sooooooooooo hard on gas they alone could have caused the fuel shortages of the 70's

 

build a 410, it will be even better!

 

My thoughts exactly, if you want to save gas, by a Japanese 4 banger. My theory has always been: my toys get what they deserve regardless the price or the time it takes to save up for the parts. We all have a wallet to worry about. So, it'll take a little while longer to get what you want, but at least you'll have what you want.
I've got a daily driver which is Japanese and supercharger(so not as boring as you'd think) but doesn't cost a fortune to run, and that's its purpose. All my toys on the other hand I never worried about the cost, time, or gas. Cause they're toys and toys are meant to be fun, fun costs money.
So build whatever you want, draw the line where in your book it needs to be drawn, but don't build under your minimum, you'll regret it and it'll cost you more in the end.

Madmike33