Now I am not try to start a fight but I was driving my '75 F100 4X4 360 fe the other day and am quite impressed with the torque that this engine produces . My question is are all 360s like this ( mine is bone stock 2bbl egr, and stock single exhaust. I am running a NP435 with 3.50 axel gears and it dosnt take much to light the tires up (235/75/r15) in second and third gears. Any way I just cant see why I would spend the money to make this engine into a 390 . In other words my engine has been rebuilt (new rings bearings and gaskets I was lucky in that it did not need any machine shop work ) My truck has awsome lowend torque ,lacks topend . I want a truck motor not a race car motor so it seems to me that the 360 is the best truck "FE" . Thats my opinon and I was wondering if any felt the same . I am NOT saying that the 390 is a pos but I dont see any reason to rework the 360 . I mean why is it that the Ford Motor Co didnt put the 390 in 4X4 trucks but the 360 is ? I did a desk top dyno comparison ( I know that dyno 2000 has its limitations ) and the 360 had a lower max rpm torque than the 390 and also its max torqe was higher but the torque curve of the 360 was alot flatter than the 390's My point is in a Truck why the 390? Is the flatter torque curve the reson ford put it into the 4X4 ? Any other opinions welcome
Jon
'75 F100 4X4 5.9
'89 F150 4X4 4.9

 

The 390 is flat out more torquier than the 360. It makes more low end power. It will not out rev the 360 in stock form. The 390 rods are touger but that doesn't really matter since you would have to get real stupid to kick the rods out the side on either in stock form. My 360 would light the tires up too but it still can't compare. If you are happy with the power you are getting from your 360 then keep it. No reason to drink more gas if you don't need or want the extra torque. Here is a comparison I did of the two. Keep in mind these are souped up but the relationship is still the same.

 

Well I suppose that if I had to send my engine out to have it bored over , I guess that the extra cost for the 390 crank rods and pisons may be worth the power gain ....but i and still wondering wy ford chose to put the 360 in 4x4 trucks why not the 390 ....I would think that the 4x4 could see more abuse , overloading and offroad use so why not put a bigg engine into it?
I worked at a shop that had a '75 F350 wreaker it was stock with a 4bbl NP435 4 speed and 4.10 axel gears . this truck would pull just about anything . Well one day comming back from Hartford the engine threw a rod ! We ordered a new engine and come to find out it was a 360! This was found out by the vin number and by us pulling the heads off and measuring ....3.5 stroke I though it was strang that it had a 4bbl it was a fo mo co intake and carb (dealer installed) a longstory short the 360 seems to be quit the work horse whereas the 68 mec with a 300 horse 390 that I worked on and road tested was a dog ...off the line but once you got it rollin you had second gear till 85 mph .....I really think that the engineeers at ford were not stupid in their choce of powerplant placement . Maybe the 360 is put into heavier vehicles(trucks) because it does revout faster then the 390 ?
Jon
'75 F100 4X4 5.9
'89 F150 4X4 4.9

 

Well my opinion on the matter, which may be a dead wrong fact, is that the 360's were put in the 4X4's to keep from breaking things. All the moving parts would last a little longer without the 390's torque trouncing them to death everyday. I doubt the 300 horse 390 was tuned correctly. It all depends on the build. 360's never came with a 4bbl even in factory crates. Not sure about the one you got. I said the 360 would rev faster but that would be at higher rpms. The engine with more torque will rev faster under load off the line. Keep in mind different gear ratios will mask or unveil an engines power.

 

As I said the intake and carb were dealer installed on the wreaker..... the Merc well it had 70,000,and had just been tuned up plus wires rotor cap points condencer fuel oil air filters with lower axel gears then the wreaker ....i disagree about the fact that the 390 may break the 4x4 parts C6s and NP435s will take quit a beating these compents are the same that were put behind a 2wd....I agree with the axel ratios limmiting an engines power 'feel" but this still doesnt point to the reason why ford chose the 360 over the 390 in 4X4s. This is a interesting topic
Jon
'75 F100 4X4 5.9
'89 F150 4X4 4.9

 

Like I said I may be wrong. You would have to agree to the fact that more torque would lessen the life of the drivetrain but if it would be enough to matter is doubtful. I just can see no other reason. The parts in the 4X4 vehicles are stout enough. There is no question there. I dunno.

 

I agree that more torque will indeed break things the more i think about this the more i tend to agree with you ....MAYBE ford thought that due to the truck being a 4X4 it my see more axel breaking abuse.........or possably the extra torque and horsepower just were not needed due to transfercase low ranges.... Maybe we will never know i'd like to find some old 73-76 sales brochers . I think i'll email ford mo co and see if they can help out
Jon
'75 F100 4X4 5.9
'89 F150 4X4 4.9

 

The 4x4 splines are half the size of a 2wd's splines,
My 360 did a pretty good job of puttin' slack in the
4x4's driveline, I getting a 390 in it for spring time muddin'.
I think a 390 would be too hard on stuff in the low range.
think how much power would be applied to the axles...

390=400ftlbs torque X 6.5 (1st gear ratio np435 I think..)

=2600ftlbs torque x 4.10 gears= 10 400ftlbs

and a low range probaly puts that number up to 20 000+ftlbs torque, now thats creepy!!!