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8 replies

I'm on a learning curve, need a few answers.

M maraudermikeMember
I bought this 1974 L about 3.5 years ago. When I purchased the car the stamping on the engine block matched the body serial number, so my guess was to take it at face value that this is the original engine. It is a 4v 4 bolt main engine. As I have been doing mechanical updates I ended up pulling the heads to replace the valves and valve guide, it was at this point I discovered that these were D0AE heads with adjustable rockers. By the book a 1974 Pantera would have been an "Q" code engine however I'm wondering if it still should be considered a "Q" code? Also were these heads considered a "Boss" head?
The other thing I encountered was that the exhaust headers that were on the car were to small of an opening, more like for a 2v head, which created an exhaust leak as soon as it burned through the exhaust manifold gasket. Purchased a set of PIM 4v exhaust manifolds which fit up as you would expect. Do I remember reading that a 2v engine was sold in the Aussie Pantera at one point? I don't have a use for the headers and would like for someone else to get the benefit if there is a need.

Any info would be greatly appreciated.

Thanks!
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rockyrockyMember
I think it's more likely that someone swapped in early heads, and had the pedestals machined down for adjustable rockers.

From one of George's posts.

quote:
351C Cylinder Head Casting Numbers
for cylinder heads manufactured in the US

1970 351C 2V (H code): D0AE (small ports, small valves, open combustion chambers, 76 cc)

1971 - 1974 351C 2V (H code): D1AE (small ports, small valves, open combustion chambers, 78.4 cc)

1970 351C 4V (M code): D0AE (large ports, large valves, closed combustion chambers, 62.8cc)

1971 351C 4V (M code): D1AE (large ports, large valves, closed combustion chambers, 66.1cc)


That's pretty easy to do. I am pretty sure the DOAE heads are early.
bosswrenchbosswrenchMember
The Aussies kept the Cleveland engine in production there until March of 1982, and among the mix built was a '302 Cleveland' installed in some of Ford/Australia's not-exported cars. This was a 2V head with a high compression closed combustion chamber, mechanical valvetrain and small intake/exhaust valves & passages for street use. Possible that your '73-74 block got a pair of these bolt-on iron heads at one point. They used to be quite popular until the flood of aluminum heads arrived- cheaper, 60 lbs/pr lighter & with better ports.

In the Pantera world, 'matching numbers' is interesting but means little to most. More important is how it runs.
George PGeorge PAdmin.
Your comments regarding the exhaust leak lead me to believe the heads have the large 4V sized exhaust ports, so I would assume the heads are D0AE 4V heads with smaller volume (63cc) quench combustion chambers, machined for adjustable valve train (studs & guide plates). A head swap is very common. The heads should have a 4 cast into the corners, without a dot. Beginning 1971 a dot was added, the 1971 - 1974 4V heads had a "4 dot" in the corner.

The engine in your 1974 Pantera was originally equipped with D3ZE 4V heads with 78cc open combustion chambers. It should also have dished pistons. Are the pistons flat tops or dished? The 4 bolt block's casting number (near the starter motor) should be D2AE-CA. An engine with D0AE heads and dished pistons is what lead me to designing the 110 LSA Cobra Jet cam which I promote in my Q code engine thread.

I can't explain why somebody would install 2V headers with a huge port mis-match. Must have got a good price?

Once De Tomaso ran out of US manufactured 351C 4V engines, the factory began using Australian made 351C engines which did indeed have smaller "2V" sized exhaust ports. There was no "2V or 4V" nomenclature amongst the Australian made engines, they all had the smaller/lower port and smaller valve cylinder heads. The heads designed for the Australian 302C had smaller 58cc quench combustion chambers, whereas the 351C heads had about 75cc open combustion chambers.

The Boss 351 was manufactured in 1971, the block had a D1AE casting number, with 4 bolt mains. The pistons were forged with small pop-up domes. It had a very thick crankshaft damper, fully bonded to the hub. The heads were D1AE castings (66cc combustion chambers), machined for studs and guide plates. Dynamic compression was around 7.6:1. The valve spring seats were machined for cups, the valve springs were slightly stronger than other 4V valve springs, and the valves utilized single groove locks. A similar engine was manufactured in 1972, the differences were use of a 4 bolt D2AE-CA block, forged flat top pistons, and open chamber D1ZE 4V head castings (75cc combustion chambers).
M maraudermikeMember
quote:
Originally posted by George P:
Your comments regarding the exhaust leak lead me to believe the heads have the large 4V sized exhaust ports, so I would assume the heads are D0AE 4V heads with smaller volume (63cc) quench combustion chambers, machined for adjustable valve train (studs & guide plates). A head swap is very common. The heads should have a 4 cast into the corners, without a dot. Beginning 1971 a dot was added, the 1971 - 1974 4V heads had a "4 dot" in the corner.

The engine in your 1974 Pantera was originally equipped with D3ZE 4V heads with 78cc open combustion chambers. It should also have dished pistons. Are the pistons flat tops or dished? The 4 bolt block's casting number (near the starter motor) should be D2AE-CA. An engine with D0AE heads and dished pistons is what lead me to designing the 110 LSA Cobra Jet cam which I promote in my Q code engine thread.

I can't explain why somebody would install 2V headers with a huge port mis-match. Must have got a good price?

Once De Tomaso ran out of US manufactured 351C 4V engines, the factory began using Australian made 351C engines which did indeed have smaller "2V" sized exhaust ports. There was no "2V or 4V" nomenclature amongst the Australian made engines, they all had the smaller/lower port and smaller valve cylinder heads. The heads designed for the Australian 302C had smaller 58cc quench combustion chambers, whereas the 351C heads had about 75cc open combustion chambers.

The Boss 351 was manufactured in 1971, the block had a D1AE casting number, with 4 bolt mains. The pistons were forged with small pop-up domes. It had a very thick crankshaft damper, fully bonded to the hub. The heads were D1AE castings (66cc combustion chambers), machined for studs and guide plates. Dynamic compression was around 7.6:1. The valve spring seats were machined for cups, the valve springs were slightly stronger than other 4V valve springs, and the valves utilized single groove locks. A similar engine was manufactured in 1972, the differences were use of a 4 bolt D2AE-CA block, forged flat top pistons, and open chamber D1ZE 4V head castings (75cc combustion chambers).


George, the description you provided of the heads fits to a T. They apparently did a very good job when they were converted as you can't see any indication that I recall of that when I changed the rocker studs. It does have guide plates.

The engine is indeed a 4 bolt main D2AE-CA block. The pistons are eye brow cut. While I haven't had the block apart the connecting rods are a D0AE number on the rod caps.
George PGeorge PAdmin.
Your description of the pistons leads me to assume they are not dished. It seems they are flat tops with dual intake valve reliefs. If so, then it is safe to assume the pistons have also been replaced.

Dual valve reliefs would indicate the pistons have close to OEM pin height (1.650"), and are probably either cast pistons or TRW forged pistons.

While the engine is apart this far be sure to replace the nuts on the connecting rod bolts, and make sure the valves have been replaced (no multi-groove style valves or intake valves having the Ford oval on the valve head). The final precaution is to replace the crankshaft damper with the Power Bond "Race Performance" damper #PB1082SS.
M maraudermikeMember
George,
Thanks for this info. In the event I ever get into a short block rebuild do you have a suggestion for which piston to go with if not using these pistons? My thoughts with this car are that is a street car, I personally have no desire for any serious track time.

quote:
Originally posted by George P:
Your description of the pistons leads me to assume they are not dished. It seems they are flat tops with dual intake valve reliefs. If so, then it is safe to assume the pistons have also been replaced.

Dual valve reliefs would indicate the pistons have close to OEM pin height (1.650"), and are probably either cast pistons or TRW forged pistons.

While the engine is apart this far be sure to replace the nuts on the connecting rod bolts, and make sure the valves have been replaced (no multi-groove style valves or intake valves having the Ford oval on the valve head). The final precaution is to replace the crankshaft damper with the Power Bond "Race Performance" damper #PB1082SS.

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