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To answer your question, as received 40+ years ago, the Pantera's 351-C had iron 4V heads with very large ports and valves. 2V cylinder heads have smaller valves and intake & exhaust ports than 4-V heads. This will affect which intake manifold and exhaust headers that will fit the new heads.
Having said that, be aware that ALL original 1970-design iron heads had too-big intakes and poorly designed exhausts compared to all current aluminum heads available. You'll get more power, better driveability and slightly better mileage from any modern heads, and a single person can remove and install an aluminum head on an engine while it's in the car. Each aluminum head will be some 30 lbs LIGHTER than an original cast iron head, which makes quite a difference in muscle-strain when you're working on your engine by yourself.
But make no mistake- it is NOT a matter of simply removing your iron heads and bolting on a pair of aluminum ones; most of the parts from your iron heads will not fit, and those few that do fit are not recommended for re-use. Consult with a Ford Cleveland shop or a Pantera parts vendor for details if you're not intimately familiar with these engines.
Originally posted by 72pantera:
I know that the early Pantera's, like my 72 has 4V, however some of the later 70's models came out with the 2V, (most shipped to Australia had the 2V heads). That being said, I have heard of some people running 2V intakes on 4V heads with good results.

I'm not sure if the original Ford iron 2v manifold with physically cover the casting of the iron 4v port. I certainly understand that there is a big mismatch, but that's not what I'm refering to.

For instance, you cannot take an original Ford version of the 4v intake and install it on the Ford A,B, and C aluminum Motorsport heads.

The head itself is cast shorter on the bottom side of the port and will have a 1/2" gaping hole.

You could fill the bottom of the 4v port with epoxy or weld it up, but you need to do something with it.

The original Ford iron heads 2v vs 4v have the same bolt pattern but the primary location of the 2v port is located to the bottom of the 4v port. In this case the top of the ports do not align.

As Bosswrench mentions, if you are talking about any of the aluminum heads EXCEPT the original aluminum versions of the 4V heads cast back in 1968 for racing, you need to stay with the manifold designed for that head by the manufacturer.

In a couple of cases, the manifolds are by Edelbrock for certain aftermarket heads.

To new comers to the Cleveland series, this could all be very confusing for sure.

Generally speaking though, if you use a CHI 3v head, you use a CHI 3v intake, a Ford Motorsport (which arenow 30 year old designs) you use the Motorsport intake, Edelbrock heads, Edelbrock intake, etc.

Some are close enough that they can interchange but usually require some sort of port matching.

Some like the CHI are so close to the Ford Motorsport that if I didn't know better, would think that some of the Aussie's lifted that design...oh wait, improved it maybe what I mean? Wink
Originally posted by DAVID KAHN:
I wish to purcase complete aluminum heads and the ad says 2v intake and 4v ports. Is this correct for the pantera?

Only one aftermarket (aluminum) cylinder head has full size 4V ports ... the CHI 4V cylinder head. The intake ports of the CHI 3V heads, the high port AFD heads and the Scott Cook heads are all actually stuffed 4V ports. The ports are a bit narrower and the floors of the ports are filled so the ports are less tall. CHI also cheats a bit and raises the ports higher than the stock 4V height.

The closest thing to a 4V size intake port amongst the racing heads sold by Ford was the intake port of the SVO M-6049-A3 cylinder head, which was a stuffed 4V port that was also raised. As Doug mentioned, since the CHI 3V intake port is also slightly raised, it aligns relatively well with the intake port of the SVO "A3" cylinder head.

Several 2V intake manifolds have extra "flange" material around the mounting flange allowing them to seal up against the larger intake port of the 4V cylinder head. The Edelbrock RPM Air Gap is one such manifold.

Notice however, that the floor of a stuffed 4V port is filled-in, where as a 2V manifold aligns with the floor of a 4V intake port. This would create quite a mis-match and would require some grinding to align things. Unless of course the alloy head in question is the CHI 4V cylinder head.

So the question remains which heads and which intake manifold are being referred to?

I'd like to mention that Scott Cook sells a dual plane manifold designed for stuffed 4V ports, its a well engineered manifold. His stuffed 4V cylinder heads, designed by Darin Morgan of Rehr Morrison Racing Engines, are the best of the standard 4V port height aluminum cylinder heads. The heads and manifold combined constitute a thoroughly modern and powerful induction system. Its hard to beat the performance of an iron 4V cylinder head, yet the Scott Cook induction system offers the potential of an additional 70 bolt-on horsepower with no other changes to the motor.

If a single plane manifold is more to your liking, two Australian based manufacturers, Terry Parker and TFC, sell high rise single plane manifolds designed specifically for stuffed 4V ports.



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Like David i am also confused about the available heads today. I am spoiled with the low end tork my 351 windsor has, i would like the same for the Pantera. The more i read the 2v gives th best low end and the 3v is in the middle with the 4v strictly for high end. Does anyone have a good recipe for a stock or even stroked cleveland that will produce around 500hp and 480 torque?
The things that will most skew the powerband of a motor towards low-rpm are:

  • Small ports
  • Small valves
  • High turbulence combustion chambers
  • Low overlap camshafts
  • Short intake duration
  • Advanced camshaft timing (early intake valve closing)
  • Dual plane intake manifolds (carburetor)
  • Smaller (650 cfm) carburetors
  • Long runner intake manifolds (fuel injection)

However, based upon many decades of personal experience I strongly disagree that 4V cylinder heads are strictly for high rpm operation. 351C 4V motors were factory equipment in Torinos & Montegos that weighed 4000 pounds or more, equipped with automatic transmissions, low stall torque converters, and 3.00:1 rear axle gearing. In other words 4V cylinder heads are quite capable of providing good low rpm power, however when hot-rodding a 351C 4V one must understand the difference between a motor with 4V heads and other motors, and make intelligent choices based on those differences.

There are many paths to making 500 horsepower with a 351C, with horsepower peaking in the range of 6000 to 6500 rpm. Dual plane or single plane intake manifolds, 750 cfm carburetors, free flowing exhaust systems (special attention paid to the mufflers), 10.0:1 compression ratio, and cams that lift the valves in the range of 0.570" to 0.620".

Cowboy from Hell, you wrote like this:

Several 2V intake manifolds have extra "flange" material around the mounting flange allowing them to seal up against the larger intake port of the 4V cylinder head. The Edelbrock RPM Air Gap is one such manifold.

Can you tell anything more about that? How does that combination really affect? I´m asking as I have been looking and thinking about that RPM Air Gap manifold. I like the look and the RPM area of it, I just don´t know how that combination works in a real world.
Originally posted by Richard S:
Like David i am also confused about the available heads today. I am spoiled with the low end tork my 351 windsor has, i would like the same for the Pantera. The more i read the 2v gives th best low end and the 3v is in the middle with the 4v strictly for high end. Does anyone have a good recipe for a stock or even stroked cleveland that will produce around 500hp and 480 torque?

Yes. The Ford Motorsport heads are a great street or track combination.

My preference is for the A3 on a 357 because I like the top end. The stuffed lower portion adds crispness to the bottom end. These really are the ones that work the best on a stroker Cleveland for sure.

Many will tell you that the C302 head is the one to use. That may be so BUT the ones that really kick ass are the ones that have been fully race ported. Ironically when you look at the finished port, they wind up usually resembling something around or in between the A3 or a worked B351 head. They can be as tall as a 4v iron head but narrower.

I have also seen a couple of sets ported that resemble a A3 stock port.

Dan Jones seems to have a preference to the A3 as well. It needs very little attention new out of the box (if you could find a set of those).

Dan Jones will tell you that the performance of the three vary with the porter. Theoretically though out of the box, the C3 is too small for a 351 (great for a Boss 302 though and out of the box the port is very similar to a 351w iron head), the B351 is about right (needing minor cleanup under the valves), and the A3 is still a little too big UNLESS you use what we used to refer as a street/track cam grind.

I tried a set of B351's on my 357 and found them to be restrictive, so I would say best dyno results do not make the most fun engine at all. In fact they seem to conflict with the actual resulting engine.

I think the phrase, "you can't drive a dyno" applies often.

The favorites of many now are the CHI 3v heads. However the CHI heads that really work well have been ported also and again start to resemble ports that are in the B351 and A3 head port dimensions.

The Edelebrock heads are not the way to go OUT OF THE BOX if you ask me.

I also think that there is no way a 351w performs with a 351c. As Grandpa Pence states, the dog 351c's are the low compression, station wagon cammed versions.

It all depends on how you drive your Pantera as well. If you just want to bop around town looking cool with your designer sunglasses and Gucci loafers on just about anything will run fine. In most if not all cases everyone is referring to gains from 5,000 to 8,000 rpms with these head, cam, header, induction systems.

Your 351w will be all done by 5,000rpm. Even so, you are still doing 120 in 5th gear at that. Most people aren't even going to have the opportunity or driving skills necessary to use the capabilities of what these combinations will produce.

A canted valve Cleveland head engine will always make more power then the Windsor head. Probably around 50hp more.

Look at the numbers on the ported 2v iron heads. first off, they are done by .500" lift. You really aren't going to be able to make 500hp with them. They will make a really nice strong 400hp combination though.

400hp is nothing to laugh at. That's a healthy engine but the aluminum heads give you at least 70 more and maybe as much as 150 more with the correct combination of cam and exhaust.

You are limited though with stock type headers in a Pantera. They are too short to make really good power.

This is all mostly building an "ultimate Cleveland" engine and as such to run with "Mad Dog" and frankly even though I can, I won't because in plain English (with all due respect Dennis) he's nuts, but it's nice to know that (theoretically), you can. Big Grin

Also as GP states, the 4v iron head can work very well with the right combinations, flowing numbers on the bench of around 330cfm, but be aware that those tend to be "Trans-Am" type engines with big camshafts, i.e./ valve lifts over .600" and real duration's around 250@ .050. I like that but admittedly with the exhausts available the car WILL sound like a 5.7 liter loosly muffled Harley.

I'm ok with that but there are those that have noticed I have anti-social tendencies and some have mumbled things about the Anti-Christ. I don't know why they look at me though, even though it is behind my back?

I really blame Cosby though. In his bit, "200 mph", he said he lived 2 miles away from work and needed a car that could go 200mph? I guess I was at a very impressionable age? Roll Eyes

...and you don't need fancy aluminum heads to make over 500 hp. This is a .030 over 351c (357) with 4v iron heads. Look at the dyno numbers.

What's wrong with 551hp?
Last edited by panteradoug
so, trying to put all the info together. If i stroke it to 393 so i can get above the 5800 red line. Use 3v heads and a decent cam lifting above .570 with compression 10.1. I should be around 500hp. All the different heads do not line up with other after market intakes like the RPM airgap by edlebrok. Does the single plan help any at low end?
Take a look at this. See if it answers any of your questions.

You could rebuild what you have presuming it is a 4v iron head closed chamber engine, with new valve train components and someone who knows how to make the iron heads flow well like McLain, that is easily a 7000 rpm engine and 500hp, even as just a plain jane.

The bottom end in a 4 bolt D2AE-CA block, crank and rods were run in Nascar and Pro-Stock back in the day. They aren't wimpy components.

You will need a really good balancer like the Boss/HO unit and you need to do something with the exhaust system in the car.

Wilkinson claims to have fixed the restrictive stock Pantera muffler problem with his repros but keep in mind that even the "european GTS Pantea" headers are showing short comings in dyno testing.

This really explains the prevelance of 180 headers in Panteras lately.

Back in the days when Shelby was running 289 race Cobras and 289 GT40's in the same races, it was thought that the "bundle of snakes" headers on the 40's were worth around 100hp under race conditions.

DJ has got "Mad Dogs" old 180's for testing but to my knowledge hasn't got around to them yet.

That test I'm waiting for since my headers were out of that same group build with the high port flanges for the A3 heads.

I won't predict what they are doing back there but as the driver I can definitely say...sumtin' goin' on back there wit um?
Last edited by panteradoug
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