The 352/390/410/410/428 got two types of heads in 1966-67. The type you have on your car will determine which header you want.

First off, I recommend FPA (www.fordpowertrain.com) because they have the best fitting, highest quality header for ya. They're not cheap, but they're still a value. The Tri-Y design seems to work as well today as it did for Shelby 35 years ago.

I run Hookers, but they crowd the engine bay a bit more, and they only fit some of the 390GT heads from 1966-67 and no 390GT heads from 1968.

Basically, if the head casting is the emissions-era C6AE-J, C6AE-U, C7AE-A, C8AE-H, or D2TE-AA, then you wanna run FPA's GT-type header. If it's the C6AE-R head, you'll wanna run the CJ-type of header.

It may sound confusing to hear that the C6AE-R head can deal with either the GT or the CJ type of Mustang header, but it works best with the CJ type.

I've gotta get a NICE digital camera so I can take some comparative photos of the exhaust ports on the head, but for now I'll just say that Ford repositioned the exhaust runner on "emissions era" FE heads so they mismatch pre-emissions heads (and also C6AE-R and CJ heads) by about 5/16". The mismatch causes more than porr flow, it also causes gasket leaks due to the poor gasket crush by the header's weld bead.

I don't presently have time to find a link to an old post which bertter describes this issue, but you might try searching this forum for the keyword "C6AE-R" or "reversion" to find some more info.

Shoe.

Maybe yes/no nice answer huh? From whit I remember of the stock log mansfolds on a 64 Ford any other manafold that would bolt up will be a improvement. I think as long as bolt patterm is compatable and there is room between the head and A-arm will fit you will have to custom make exhaust pipes.

The truck manifolds have larger outlets and are angled differently than the car manifolds. You might be able to get the driver's side to work but I doubt the passenger side.

They should be worth about $500.00 each. Put them on E-Bay if you want top dollar.

Royce Peterson
68 Cougar GTE 427 XR-7 (two of them)
68 Cougar XR-7 428 CJ Ram Air

Most of the "cobra" labeled intakes were Shelby units made into the early 80's and not original Shelby 60's pieces. Buyer beware. Still cool. Just not old.

Are they Tunnel-Port or Tunnel Wedge intakes?

Tunnel Port intakes have the pushrod running straight through the intake runner and will only fit Tunnel Port heads. Tunnel wedge intakes have the pushrods running through the manifold just to the side of the port.

Tunnel Port intakes sell as high as $1500 mint and tunnel wedge sell at $500-750 (2005)

Need to consider deck height, gasket volume, piston, combustion chamber, overbore and valve depth to calculate compresson ratio. Anything less is an excersize in futility.

Ford officially rated the D2TE-AA heads the same as the C8AE-H heads of '68-'71. I forget the exact decimal places, but it was 68.1-71.x the best I can recall.

One thing to note is it seems Ford may have occasionally sampled the C8AE-H heads for chamber volume because of the 10.5:1 engines of the period, but some folks seem to have found the chamber volume of the D2TE-AA heads can step outside the factory specs. This may be due to the very low compression of the truck motors - a "cc" here or there wouldn't do much to affect engine operation, so the actual production line "cc" spec may have gone unmeassured in the truck-only years of the FE.

JMO,
Shoe.

In your case (1965 and earlier), the stock heads will breathe better than CJ heads.

The 428CJ got the same intake runners, exhaust runners, and valve bowls as your heads, but the CJ also got restrictive Thermactor emissions bosses cast into the roof of the exhaust runner. Assuming you install CJ-sized valves in your stock heads, the CJ would have to have the emissions bosses ground out to flow equivalently. Note that CJ heads are cast for the common FE valve sizes but are throat dressed at the factory to fit CJ-sized valves.

The reason the 428CJ is such a hot engine is it got an MR-style intake manifold, and those suckers flow like crazy. It also got satisfactorily designed unibody exhaust manifolds, which is something the 390 unibody cars did not get.

If you are looking for some extra zip from your full-sized Ford, then you should focus on the intake manifold, cam, lifters, and valve springs. An Edelbrock RPM intake would suit you well (even with the port mismatch), and the cam kit will finish it off.

Headers are kind of a radical upgrade, but they'll buy you lots of HP once the intake and cam is in.

The tranny should be able to handle what you give it. It's not as sturdy as a C-6 (and not nearly as fun to work on), but it's a tough tranny. You might find that it'll need fresh clutch plates (a standard rebuild kit) if you start pumping extra horsies through it.

I have heard some claims that the FMX tranny will fall apart with any kind of abuse, but I'm learning these are apparently incorrect statements. One thing I do know about your tranny is that since it's design is based on a 2-speed Fordomatic that got an extra gear grafted on, that it's a rather complicated tranny to "learn" on, as far as doing a clutch-replacement. I've never had any problems taking them apart, but I still can't figure how to get them together again. I'm sure my difficulty is partly because I mainly take FMXs apart to claim the cool-looking mainshaft and I don't actually attempt to reassemble them because I only use a C-6 or toploader in my cars. Still, the C-6 is much easier for the first-timer.

Shoe.

I've been throwing around the same questions because I've recently acquired a 65 390 to drop into my 66 Fairlane. So, if the port design doesn't make as much difference as the intake/exhaust design, I've had the performer rpm on a chevy 350 in a 51 Merc (Blasphemy I know, but I didn't put it in, I bought it whole) and it really ran great with A holley 600 vaccuum seccondary. Would the same Intake/carb be sufficient for the 390 or would I have to go to a bigger carb? Also, the Motor came out of a full size merc , so do the stock manifolds breathe well enough, will they fit into the fairlaine without too much trouble (I'm doing a custom dual exhoust anyway) or should I not screw around and just throw a set of headers into it since it's out anyway? Also, any cam preferences? Thanks for the help.
Eric

n/m

Ford stopped listing horsepower for the FE truck engines around 1972, and compression was no longer listed about 1973 or so.

The 360 is always a couple tenths lower in compression than the 390 truck, and 390 truck engines started out around 8.5:1 (foggy memory) (360 around 7.8:1?) in 1968 and bumped their way down in compression as the years passed. I suspect the 360 ended up around 7.4:1 in 1973-76 and the 390 ended up around 7.8:1 the same time. The cam never changed on the 360/390 truck engines their entire run from 1968-76.

I posted some stuff on this in an FE forum maybe a half year back when I first learned the details, but can't remember this stuff very well and can't quite remember where I posted it. If I remember where they are, I'll post a link.

Shoe.