390 heads on a 352. Why not?

[p38fighter]

The 390 bore is 4.050. My 352 block is bored to 4.040. Does that .010 make a difference? Why? Is there something else that prevents the use of the 390 head on a 352?
Thanks..

[StealthSRT10]

I have 352 heads on a 390 block. I dont see why you would have any issues. since the head gaskets are the same size.

[p38fighter]

Thanks - A question is whether the ports on the 390 heads would match the intake and exhaust manifolds on the 352.What did you use for manifolds?

[StealthSRT10]

the stock ones. i believe all 352 and 390 have the same pattern bolt holes. you should just be able to eyeball it and its either the same or completely different.

[simplyconnected]

Your question is VERY valid. Ford made at least 50 different combinations of heads/intake manifolds. The changes were made over many years. Would you put valves that fit a 332 on a 427? They fit but that would be a terrible waste when a 427 is choked using 332 valve sizes. So, early FEs and later FEs are different.

Edelbrock offers aluminum heads for 390/427 but the same heads won't fit a 352. Why? Because the valves hit the cylinder walls on a 352. These heads barely fit the 390 and are better suited if the 390's bore is opened, even a little bit. If you want specifics, here's the phone number of the Edelbrock Technical Support Team: 800-416-8628.

For questions regarding heads and intakes, I usually ask to see them together instead of trying to match different combinations. - Dave

[pbf777]

Is there something else that prevents the use of the 390 head on a 352?

No!

Butt!

The Ford O.E.M. cast iron cylinder head will bolt on, with the concerns of valve clearances being not relevant as the valve diameters of 2.02" (intake) and 1.55" (exhaust) were used in both, and the valve spacing is also constant in both standard casting configurations. There is the concern for the exhaust bolt pattern as there is the eight bolt as used in the 352s' and 390s' in '58 - '77, but also the fourteen bolt pattern unique to the 390 GT casting of '67 - '69, which would not accept the O.E. cast iron exhaust manifolds from the 352 cu. in. engine. The intake bolt patterns are the same for all other than some unique castings and we won't inject the 427 cu.in. units into the conversation which are not relevant here, but there are basically two intake port dimensions, the taller port as witnessed on the 352's, 390's, 410's, etc., with the exception of the shorter height port of the "GT" casting, whether drilled for the eight or fourteen bolt exhaust pattern, but although it may not look proper the intake manifolds will interchange and function acceptably. The other possible difference depending on the specific castings selected would be the combustion chamber volume, as this may be found to be anywhere from approximately 58cc +/- (as in Squarebirds) to something in excess of 70cc + in some 390's.; this effecting the mechanical compression value.

If one wishes to use the after market cylinder heads such as the Edelbrock, these being approximately 72cc chamber volume, then one would also establish through observation that adequate clearance between valve to cylinder wall existed, as these units utilize a 2.08" (intake) and 1.66" exhaust with relocated valve positions. I would inspect this whether it was a 352 + boring or even a 390, and provide reliefs if necessary.

Scott.

[p38fighter]

The heads I'm looking at are C8AE

[pbf777]

The heads I'm looking at are C8AE

Sorry, not enough information, as the number you supplied is incomplete lacking the suffix, as in C8AE-A, H, J, R, or? But, I would guess that the casting is of the "GT" variety, and presents at the exhaust flange the additional casting bosses which may be drilled for either the eight bolt or fourteen bolt configuration pattern; the later identifying it as a true "GT" cylinder head intended application. If so, then in comparison to the '58 - '60 352 head castings, as stated previously, one will note that the intake port presentation at the flange is somewhat shorter, and of no great consequence, and the combustion chamber is approximately 10 cc greater in volume, thereby reducing the compression ratio by perhaps as much as in excess of one point. None of this precludes their ability to be implemented, but just be aware.

My recommendation would be to have a set of the proper 352 head castings of the period rebuilt, whether your originals or a replacement set. If one wants to be somewhat more "sporty", then look for the '60 - '61 352 H.P. castings (casting #'s COAE-D or -H, as I recall); unless had from the unknowing, one will pay a premium for these, but one can brag to all your friends, "hey look what I got"!

And if one does chose the "warm-it-up", "some", route, then if using the "GT" head castings, other possibilities: pick-up the '67 - '69 "S" intake manifold, or even maybe the '69 - '70 428CJ "C" suffix intake, as although not correct original units, they are FORD pieces, sorta back then period hop-up, and of cast iron, so may not be so noticeable a modification, if that should offend anyone, and should provide some potential benefit performance wise.

Scott.

[pbf777]

Would you put valves that fit a 332 on a 427? They fit but that would be a terrible waste when a 427 is choked using 332 valve sizes.
Dave

BTW, just a note:
This is exactly what Ford Motor Co. did in creating the 427 engines for the GTE Cougars in '68, and for the 427 Marine engines for the likes of Chris-Craft. In these applications Ford utilized the 390 "GT" castings (14-bolt) if only for ease of fitment in the case of the Cougars, and the 8-bolt configuration of the same for the marine applications. Although technically not "332" heads, the valve sizes are the same.

Scott.

[p38fighter]

Scott,
They are H castings. And have the 8 bolt configuration. Thanks for your continued commentary...Chris

[simplyconnected]

...If one wishes to use the after market cylinder heads such as the Edelbrock, these being approximately 72cc chamber volume, then one would also establish through observation that adequate clearance between valve to cylinder wall existed, as these units utilize a 2.08" (intake) and 1.66" exhaust with relocated valve positions. I would inspect this whether it was a 352 + boring or even a 390, and provide reliefs if necessary.

Scott.

The only reliefs possible would be to grind off some of the block! Noooo, I don't suggest anyone do that.

Instead, use a block that was made with enough bore size to accommodate Edelbrock heads. BTW, Edelbrock intake valves are 2.090" diameter in their Performer RPM Heads (60069)

Ford installed far more 390s in all their car/truck/construction/marine applications than all the other FEs combined. (Even the Mustang sported a 390.) That's why aftermarket offerings cater to the 390/427/428 crowd, the largest group of FE consumers. I see 390s on Craig's List and local swap fliers which means they are tucked away in people's garages and in engine machine shops.

[pbf777]

Scott,
They are H castings. And have the 8 bolt configuration. Thanks for your continued commentary...Chris

Yes, the -H suffix is as I described, the "GT" casting; but as machined with the 8-bolt exhaust configuration it did not appear in this application rather say anything but the Mustang or Cougar chassis.

Scott.

[StealthSRT10]

Thats true my buddy in Norman Oklahoma has a 390 2 barrel sitting taking up space that he doesn't need or plan to use on anything. i think he started to take it apart somewhat this last week. if someone needs heads or a block im sure he would let it go at a super low price. I do believe the motor was locked up. so would need a rebuild.

[pbf777]

The only reliefs possible would be to grind off some of the block! Noooo, I don't suggest anyone do that.

Instead, use a block that was made with enough bore size to accommodate Edelbrock heads. BTW, Edelbrock intake valves are 2.090" diameter in their Performer RPM Heads (60069)

Yes, you are correct, the standard intake valve for the Edelbrock head is 2.09" sorry for the typo, my bad!

As far as for the reliefs, if required, no, I guess I wouldn't suggest that just anyone would be capable either, as there are some who can't tie their own shoes, but it is an acceptable and not so uncommon a process in the construction of engines in the performance industry. Even Ford Motor Co. in their Autolite-Ford HI-PER PARTS catalog printing of the late '60's, pertaining to the "Special High Performance Parts For Ford 390, 406,427,and 428 C.I.D. Engines" and "How To Modify Your Ford Big Block Engine For Street And Strip" suggests the process to be executed by individuals of "bore chamfering to provide sufficient valve clearance", when for example intending to utilize the 427 castings on say the 406 or 428 blocks. So it is a feasible operation in general consensus, but if one is not comfortable in such, then services can be contracted.

Scott.

[simplyconnected]

...If someone needs heads or a block im sure he would let it go at a super low price. I do believe the motor was locked up. so would need a rebuild.

I buy engines with the intention of overhauling them. I want to know two things, is the block casting good and has it been previously bored. All the 'stories' about the engine's history means very little since I'm overhauling the whole engine and trans.

I like buying the complete engine and trans TOGETHER, that way I know all the parts are there. For example, I don't want the heads but I do want the rocker arm shafts, stands, bolts etc.

Oklahoma is a bit far for me (in Michigan). To keep shipping costs down I buy locally. - Dave