Where on the head are the numbers stamped for ID'ing?
Will
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The casting # is on the bottom of one of the intake runners. You can't see it without removing the head & flipping it over.
If the head has a plain 4 in the corner, its a 1970 (D0AE). If it has a 4 & a "dot" its a 1971 or later (D1AE, D1ZE, D2ZE, D3ZE).
-G
If the head has a plain 4 in the corner, its a 1970 (D0AE). If it has a 4 & a "dot" its a 1971 or later (D1AE, D1ZE, D2ZE, D3ZE).
-G
So, if you have a 73 engine and want to obtain the early horsepower claims and the higher compression of the earlier engines ( 1970-71 ), can it be done to the later head? In other words, what exactly changed with the later engines and how can it be reversed without looking for a set of early heads? Are the valve sizes and ports the same?
quote:Originally posted by Cowboy from Hell:
The casting # is on the bottom of one of the intake runners. You can't see it without removing the head & flipping it over.
If the head has a plain 4 in the corner, its a 1970 (D0AE). If it has a 4 & a "dot" its a 1971 or later (D1AE, D1ZE, D2ZE, D3ZE).
-G
If you have the intake off you can use a mirror to see the code letters.
Mike
If the engine is 100% stock there's plenty of "other" ways to determine what you got. The cast iron intake manifold makes it a slam dunk because D1ZE heads were used in conjunction with D1ZE intake manifolds, D2ZE heads with D2ZE intake manifolds, D3ZE heads with D3ZE intake manifolds.
D0AE intake manifold used in conjunction with a head that has a 4 in the corner means you have D0AE heads. D0AE intake and heads that have a 4 'dot" in the corner makes them D1AE heads.
Only cobra jets had dual point distributors, single point distributor means you have an M code motor, M code motors had heads with closed combustion chambers.
D0AE heads have the smallest closed chamber style combustion chambers, nominally 62.8cc, and of course the big valves.
D1AE heads have nominally 66.1cc closed chamber style combustion chambers & big valves.
D1ZE & D2ZE heads have nominal 75.4cc open chamber style combustion chambers and big valves.
D3ZE heads have nominal 78.4cc open chamber style combustion chambers and the smaller 2V valves.
Reworking D3ZE heads seems a complete waste of time to me because D1ZE & D2ZE heads are cheap enough to obtain on eBay. The best heads are the D0AE heads & the D1AE heads aren't too far behind. These are the closed chamber heads, they sell for more money.
Ford's 1970 & 1971 351C compression ratio figures are in error. Either the sales department miscalculated the compression ratio, or they were intentionally misleading people. The actual compression ratios are:
1970 4V = 10.0:1
1971 4V = 9.7:1
1971 cobra jet = 8.8:1
1972 cobra jet = 8.8:1
1973 cobra jet = 8.0:1
D0AE intake manifold used in conjunction with a head that has a 4 in the corner means you have D0AE heads. D0AE intake and heads that have a 4 'dot" in the corner makes them D1AE heads.
Only cobra jets had dual point distributors, single point distributor means you have an M code motor, M code motors had heads with closed combustion chambers.
D0AE heads have the smallest closed chamber style combustion chambers, nominally 62.8cc, and of course the big valves.
D1AE heads have nominally 66.1cc closed chamber style combustion chambers & big valves.
D1ZE & D2ZE heads have nominal 75.4cc open chamber style combustion chambers and big valves.
D3ZE heads have nominal 78.4cc open chamber style combustion chambers and the smaller 2V valves.
Reworking D3ZE heads seems a complete waste of time to me because D1ZE & D2ZE heads are cheap enough to obtain on eBay. The best heads are the D0AE heads & the D1AE heads aren't too far behind. These are the closed chamber heads, they sell for more money.
Ford's 1970 & 1971 351C compression ratio figures are in error. Either the sales department miscalculated the compression ratio, or they were intentionally misleading people. The actual compression ratios are:
1970 4V = 10.0:1
1971 4V = 9.7:1
1971 cobra jet = 8.8:1
1972 cobra jet = 8.8:1
1973 cobra jet = 8.0:1
Ok, so what I am getting from Cowboy's response is that the best solution is to get some D0 or D1 heads and use them on a later motor ( if you have a later car ). Will the stock 03 or 04 exhaust manifolds match up? Are there any deck height issues?
Sorry, what I meant to say was 73 or 74, not 03 or 04.
quote:Will the stock 73 or 74 exhaust manifolds match up?
Yes.
quote:Are there any deck height issues?
No.
Ford iron (standard production) Cleveland heads and blocks are all interchange compatible.
Cuginflyer, the difference in the early (closed-chamber) heads is in the way the combustion chambers were machined. There are two cast-iron 'eyebrows' that overhang each chamber and cause the piston to approach very close to them at TDC. This not only increases compression ratio, it squirts two streams of fuel-air mixture out into the middle of the chamber, creating high turbulence just as the spark plug fires. This turbulence reduces the octane requirement of fuel needed to run knock-free. The result is a good 50-60 bhp increase over the later 'open-chamber' heads, on 91-octane gas. Adding domed pistons to open chamber heads will increase the compression but not the turbulence of the closed chamber type. The result is, open chamber heads in almost any combination of parts will not produce the power of a set of closed chamber heads, and if they do, it will be on 106-or higher-octane fuel. Advise not wasting time trying to improve open chamber 351-C heads, which will be most U.S castings after 1971.
Other factors to consider are- being machined for an adjustable valvetrain rather than hydraulic lifters and sheet-steel rocker arms so one can use mechanical or roller cams, and the use of smaller intake & exhaust valves such as in the '2V'- heads use. So- called 'Aussie' closed-chamber cylinder heads were made with the high compression of the U.S. closed combustion chamber '71 4V heads but with the smaller ports and valves of 2V heads. "Smaller" valves are relative, incidently- 2V valves are still larger than the biggest valves useable in a modified 350 Chev cylinder head. The result for 2V closed chamber Aussie heads is much more midrange power and better drive-ability than is possible with the huge "4V" valves in any head.
Other factors to consider are- being machined for an adjustable valvetrain rather than hydraulic lifters and sheet-steel rocker arms so one can use mechanical or roller cams, and the use of smaller intake & exhaust valves such as in the '2V'- heads use. So- called 'Aussie' closed-chamber cylinder heads were made with the high compression of the U.S. closed combustion chamber '71 4V heads but with the smaller ports and valves of 2V heads. "Smaller" valves are relative, incidently- 2V valves are still larger than the biggest valves useable in a modified 350 Chev cylinder head. The result for 2V closed chamber Aussie heads is much more midrange power and better drive-ability than is possible with the huge "4V" valves in any head.
thanks to Bosswrench and Tp 2511 - this is great information. I have not yet purchased a Pantera and have been struggling with which year to pursue. I like some of the assembly improvements of the later cars, but prefer the styling and definetly the engine specs of the earlier car. Now, with your help, I know that I can bolt on the combo I want in a later car to get the great performance that made the Cleveland a great motor ( Bosswrench's description of the design reminds me of the "May" or "Fireball" head design used when Jaguar redesigned the heads of their V12 back in the early 80's - Same principle.). I used to watch well built Clevelands walk away from Chev powered sprint cars when I was younger. Thanks for all your help. I may need a little more help as I get farther into this. I'm impressed with your detailed knowledge.