I just bought a 360 engine core. It was rebuilt about 20k miles ago. And a refreshed top end; new seats, guides, and seals but old valves, springs, retainers and keepers.

I'm looking to refresh the bottom end and add a 390 crank and rods. What vehicles might I find a 390 crank in and if all of the FE motors are cast with 352, how will I know if a motor is likely to have the correct crank?

I also bought Barry Rabotnick and Steve Christ's books.

Keeping in mind that I'm not trying to spend a fortune and not looking to build high performance racer, what else should I consider updating?

Thanks,
Joel

 

Get yourself a dowel rod and start measuring strokes.

 

Its there a list of vehicles somewhere, that are likely to have a 390 engine, and are there markings on the block that would distinguish the 390 from a 352, 360, etc?

 

There is no way to determine FE engine sizes by numbers cast on engine blocks or by looking at them, as all pretty much look the same.

Thru circa 1971, 352 is cast onto the block, but this is a foundry mark only, as all FE's were cast as 352's. So, it could be a 352, or who knows.

You will need a 390 used after 1964, as 1961/64's were only installed in cars, have a different engine block bolt pattern for the front rubber insulators.

1958/64 FE engines have rounded valve covers without holes in them for smog valve/oil cap. There's an oil fill tube on the right (passenger) side of the engine.

1965/76 FE engines have pent roof shaped valve covers with holes in them for oil cap/smog valve.

The list of vehicles that came with 390's is mind boggling, too extensive to list. Plus, other FE engines were also available in these same vehicles.

 

I have a running 390 FE. But I have no idea where ya live. Must have missed it.

 

start looking for cars- the 360 never came in cars, so if you find a FE, it'll either be a 352 or a 390.

but yeah- as everyone else has said...there's absolutely no way to tell from looking at it.

 

Arctic y Block, I'm in Northern California. I an told that the bottom end should run just fine, but it's a 360, which I read wasn't a very good engine; a low compression, gas hog, if I remember correctly. I was told if I just changed out the crank and rods it would be a very good engine...

NumberDummy, I was hoping you would comment. I was also hoping you would have better news for me... But I am thankful for your input.

I guess I could use the heads from the new motor and use bottom end of the motor in my truck, using the crank from the 360 if the 352 in my truck needs it... But having such so fresh 390 / 360 (still has nice hone marks, and looks pretty clean) seems a shame not to use it.

 

the 360 is a perfectly good truck engine- just 30 cubes smaller than the 390.

 

Better heads, headers and after market intake alone will make a 360 squall.

 

So, Rustywheel, in your opinion, do I use the new engine to repair the 352; put the 360 with the refreshed heads together and call it a day; or look for a 390 crank and rods to create a 390?

If the option was your to make, what would you do for a daily driver.

 

I thats also an option I hadn't thought about. But out seems that aftermarket, intake, carb, better heads and headers would cost a pretty penny... I'm guessing, but I thinking, bang for the buck...

 

Think of an engine as a big air compressor because it is kinda only backwards. So the more air in and out with the least restriction will produce the fastest and cheapest horses.

 

Unless you have a '65 F100/F250 4X4 or '66 F250 4X4.

How is the bore and pistons in the 352? If it were me, I would give the 3.5" stroke crank and matching rods to someone in need.

The 390 crank and rods would work in the 352 block using stock 352 pistons and they would work in a 360 block using stock 360 pistons.

I would be tempted to make a 380 out of a 390 crank and 352 block. That should be the best combination for gas mileage.

Unless you have a turbo though, there is no replacement for displacement.

 

I like the idea of the 380, the problem is, and I probably didn't make it clear up above, is I don't have a 390 crank. Unless there is one in the 360 block...

I have a question about the dowel rod.

I'm guessing, the dowel rod suggestion would be to pull a plug and stick a dowel down the plug hole and measure how far down to Bottom dead center... So, how far would the dowel go down on a 390 compared to a 352... Or maybe I'm over thinking the dowel rod suggestion.

Please explain if you have a minute.

Thanks,
Joel

 

360 and 352 have a 3.50 inch stroke, so the dowel or wire will move about that much, depending on how straight you can keep it.

The 390 has a 3.784 stroke, so look for just over 3 3/4" of movement.

http://www.clubfte.com/users/ratsmoker/FAQ.html

Car 390s became almost the "standard" engine in '66 (in full size cars--Galaxie and Mercury full size) with the advent of the "Regular Fuel" 390 2v. The last year of the 352 was '67. So from '68 on, mostly you'll find 390s in cars. (427s and 428s were rare and more prone to being blowed up....) Some in Mustangs, Cougars, Fairlanes and Comets, but again the blow up/wrecked rule applies to those vs. the more conservatively owned and driven full size 4 door sedans and wagons.

In pickups, mostly you'll find 360s starting in '68. No 390s in 4x4s, but tons of FE motors up until the end of '74. So, measure away.....