If anyone has read my recent threads, they will know I blew out a main cap in my '65 F100 with a 390. Well, turns out that not only did it put a hole in the oil pan, but punched the block out too..time for a new engine.
I have a spare block laying around that was the original 352 for the truck.

I'd like to see if its possible to save the 390 crank and have a machine shop bring it back to a usable condition. Id also like to try to save the rods.
So, my question is..what pistons should I be looking at for this engine? Crank and rods will be for a 390, and I'd like to make a 10.5-1 compression ratio or better.

Heads are c8ae-h fresh from the machine shop.

Right now my shopping list is as follows:
Pistons and rings
Bearings
crank ground and polished
oil pan
And all the other little things like timing set, gaskets etc..

I'm not building a million horsepower deal, as this will be on a budget, but I'd like to get the most bang for my buck, especially since I'm starting from a bare block.

Any advise from the wise?

 

Stock 390 pistons from the mid to early 60s should give you about 9.25:1; unless you are upgrading in other areas that is all the compression you need.

 

I was reading in '68 they built a 390 with a 10.5-1 ratio...I can't seem to find out what pistons were used though.

 

That is about right for some of the early performance versions; of course you were buying a more a-tuned fuel when they were in production. Even then you were supposed to fill with higher octane gas.

 

I've always filled with 91- no ethanol..it would be nice if I could get the most out of that fuel with the given cubic inches.
My mentality is, they did it 50 years ago, I should be able to do it today..with out going nuts with stroker kits and whatnot.

I'm having a hard time finding any pistons with less than a 100cc dish in them. I'm not completely on my A-game in this area, but what are the chances of finding a true flat top piston (as far as cc's are concerned) or even a dome style?

 

I would think your machine shop/engine builder's measurements of your old 352 block would dictate the size pistons you can use. Remember the stock bore on the 352 was 4.00 inches. The 360 and 390 bore was 4.05 - 50 thousandths over stock 352. Some blocks can tolerate that much overbore, some can't. It may have been overbored already - you didn't say or don't know. There was a 401 horse 390 offered by the factory in '61 and '62, but it had solid lifters, 11:1 compression, three deuces, special heads, special exhaust manifolds. There was also a 360 horse 352 in 1960. Good luck finding those parts at affordable prices. Remember, when those engines were available, so was 100 octane leaded gas for cheap. Your engine builder can massage your compression ratio to whatever you want, just remember that what passes for gasoline today would have been called cow **** back in the 60s. Good luck with whatever you do.

 

My 416 is around 9.3:1. I have the timing at 12* and it will detonate if I don't run 91 octane.

 

I appreciate the input..all good stuff.

Speaking of overbore Supersabre, I've always been curious what dictates the amount of bore these old blocks can take. Whats stopping me from boring it out to a 428 for example? Just curiousity at this point. Eagle specialty products sells a stroker kit that requires a 4.160 bore, but displaces 462CI.
One can always dream..

 

Nominal or advertised 9.5 "Regular Fuel" 390 2bbl used a slight dish with valve reliefs.

10.5 used a flat top with valve reliefs. Piston to deck was .015 or so for both. Specs on '60s motors here:

FE Series Engine Specification Chart

Page 43 or so shows the 390. You will be looking at a compression height of 1.76. They also show pistons with a 1.66 compression height. Those are actually 410 car motor pistons, which yielded 10.5 on top of the long stroke of the 410. In a 390, they end up down the hole with low compression for pickups motors.

https://www.uempistons.com/catalogs/...te_catalog.pdf

 

The first thing that might stop you is trying to find a piston larger than 0.060" and your example would need a 0.160". I'd be curious what the extra weight of that larger piston would do to the rotating assembly.

Second, Ford recommends no more than 0.060". To go beyond that would require sonic checking to be safe. A too thin cylinder will lead to an engine running hot, possibly very hot.

 

O YES,,, the good ol days when fuel was fuel. Remember Conoco gas stations with their 'dial an octane' wheel on the pump. Big silver **** - just turn it to the octane you wanted. They all went up to 100 octane but some of them, at least some of them in Albuquerque, had 120 octane. Hotrod heaven. You can only get good fuel like that at your local small airports. At least in large quantity. AND you will PAY.

 

understand what your, saying..makes sense in my head.
However, what seperates a 352 block from a 428 block? I thought all the blocks were pretty much the same.

 

Why don't you just drop in a 460? I have one in mine; it bolts right in using 70s motor mounts and would be a whole lot cheaper than messing around with a FE block. Getting the right piston, rod and crank setup can be problematic.

 

The blocks are pretty much the same only the 428 was designed with the bigger bore and piston. You can bore out the 352 0.0130" but you will not find any pistons for it in that oversize. Now if you went 0.160" over, a bigger risk, you can find a set in that size. Forged of course and around $100 each.

As Old Rusty said if you really want power for less bucks then put the 460 in. One can build the Ford FE like I did taking a 360 to a 390 which is easy. Can you take a 352 to a 428? Possibly, but as most FE guys know the Ford engine isn't cheap when it comes to that sort of thing. You can do it but is your budget large enough?

Funny thing to me is every one wants more horse power out of their Slick. Then I look at my truck with it's older designed suspension, manual steering and manual brakes and go you gotta be nuts. I'm not taking this thing to the track for a 1/4 mile run and on the street if I got going fast then everybody in front of me better look out. So I opted for torque and the ability to cruise between 45-65 in style...

 

Ha ha ha I was waiting to see if anyone else would mention what "real" high octane was - not to mention it was leaded fuel. In the 60's, engines were built with 10:1 and even up to 11.25:1 compression in some 396 and 427 chevy engines if I recall correctly. It wasn't an issue with he fuel that was around then. My Dad had a bone stock 71 Mach1 351C with 10.25:1 (last of the power era) and by 1978 / 79, we couldn't get 102 Octane fuel for it. We had to back off the timing on it to stop the run-on and pinging. Todays HP engines are all top end, lower compression engines. Superchargers, Turbochargers, etc. You just don't get that Big Block stomp on it G-force pushed back in the seat power anymore. If you wish to drive the truck on the street without a lot of headache, stay away from the higher compression...my $.02