Since he has a 360 and is planning on swapping cranks to a 390 crank, a 0.040 overbore should give him MORE than 390 cid. Should be about 398.

You must be thinking it's a 352. Right?

 

Guys, 360s suck. All of them. Yes, some of them run well, and they are durable, but the only good thing about them is that they are so easy to convert into a 390 or a 410. The problem is penny-pinching and lazyness at Ford. The factory wasn't able to provide enough engines in the 350ish size range. So Ford did what was quick and easy. They had thousands of leftover 352 cranks and rods..... and lots of leftover flattop pistons from the 390 4V that wasn't being produced in large numbers anymore.....so viola! 352 crank and rods into 390 blocks, and we have an instant 360. The problem is that the assembled height is too low, the piston is about an eigth of an inch below deck at top dead center. This means you have no quench action. To have good quench, you need to be between .030 and .060 clearance. The only way to achieve this in a 360 is with a custom piston. With a 390, there are lots of pistons available to easily get the needed quench. Ford didn't limit their piston nonsense to the 360. When Ford wanted lower compression in its 390 truck engine, they reached into the leftover parts bin again. The production of the Mercury 410 stopped after '68. And then what to do, what to do, with the molds for the 1.65 tall, 4.050 bore, dish top piston the 410 used to use ? How about we drop them into the 390 ?! Why how about that ! We now have a 7.9 to 1 compression truck engine. The better way to go would have been to design a new 390 piston, maybe with a bigger dish or something, that had decent quench and low enough compression for a pickup, and the new at that time unleaded fuel. The 390 pickup truck engine suffers from the same problem of not enough assembled height. Unfortunately, 9 out of 10 390s that get rebuilt, car or truck, get replacement pistons that repeat Fords unquenched mistake. It is that way too open quench that makes the 360 and 390 truck engine ping so easily and get poor mileage. Guys that have the too open quench problem just don't realize just how much more power and mileage they could be getting. DinosaurFan, on work's old cast off 'puter

 

Sorry, my mis-read. Yes a 360 has the 4.05 bore. Fore some reason was thinking 352.

 

Cool post. :)

Hey, lets keep that information over here on the FE forum tho ok?

All those other guys don't need to know that stuff ...keep 'em green with envy they don't have FE's! :)

Alvin in AZ
ps- i know what to do when i rebuild my FE again :)

 

how yall doing i have a 390 just got it and went out playing all of a sudin i had no oil pressure and when i poped the hood i have oil spraing from the side of my head in between #1 spark plug and #2 exhaust port above the exhaust manafold any one know of any thing?

 

There was a '361XD' 4bbl., which was a heavy duty version of the 360 used in F-600 and larger trucks up until 1978. Also, a good many U-Haul F-350's had the old 330 FT up until '78 as well.

 

yea i have found a 361 xd at a junk yard would it be worth changing out for the 390?

 

To each his/her own. My '75 F-250 Ranger SC came w/ a 360-4V, NP435 and a D60, from the #'s on it. It will be bored .030 and stroked w/ a 390 crank and other parts. It was running quite strong until my EX son-in-law ran it out of oil. I'd like to keep the original block for matching #'s if possible. My wife thinks it's goofy to make a "small" racing motor in a farm truck. It's also a camp rig and I want more power to pull the passes with a full load. The 4.10 open will get changed to a higher LSD too.

 

So tell me what numbers are for a 4 barrel on a 360? Since the factory never produced one, this should be interesting. FYI, torque is pulling power, horsepower is top speed, so unless you are gonna run the pass in first or second gear, big horsepower is not what you want. Also the higher ratio/lower number rear gears hurts towing power as torque is multiplied by gearing, horsepower is not. That's why the factory used 4.10 rears in work truck.