Still trying to determine my engine

[Hemikiller]

What is the better head to have for a Cleveland, the open chamber or closed chamber? The stamping number on my head is D1AE-GA and the dates codes are 0F17 and 0G24. My heads have the 4 on the corners but no dot on one side and doses have dot on the other side?

The D1AE-GA heads are 71 model year closed chamber. They are 67cc nominal chamber volume, vs the 70 D0AE-x heads which were 63cc nominal. 0F17 is June 17, 1970, so that's a very very early 71 head. Having no dot is seen only on 71 heads in the first month or so of production.

D2AE-CA is the basic 72-74 351C block casting number. It was used on the 71 351CJ, and all 71-74 351C engines. It can be machined for 2 or 4 bolt mains.

"Better" is a subjective term, which depends on what you're looking for. The CC heads are the desirable head for most 351C guys, as most equate compression with power. OC heads produce great power too, and may flow better than a CC head due to less valve shrouding. The CC head has excellent "quench" if the short block is built properly, and can run quite a bit of compression on regular pump fuel.

FWIW, you have stock Ford valves. Unless you are doing a stock rebuild, those go in the trash. The keepers and retainers as well. Replace them with a quality single groove stainless valve, keeper and retainer setup. Springs need to match your cam. If you want to take advantage of the closed chamber's quench qualities, buy a piston from RaceTec/AutoTec with the proper compression height to attain at or near zero deck height. The pistons are more expensive, but are lighter and better designed than the now $450 L2379F TRW forged slugs, which will save on machining and balancing costs.

 

[tpj71mach]

Here is a picture of the engine before I sent it to machine shop I can't quite make out the date code on the tag for the engine. I think it might say 2F4, maybe?

 

[tpj71mach]

The D1AE-GA heads are 71 model year closed chamber. They are 67cc nominal chamber volume, vs the 70 D0AE-x heads which were 63cc nominal. 0F17 is June 17, 1970, so that's a very very early 71 head. Having no dot is only seen on 71 heads this early.

D2AE-CA is the basic 72-74 351C block casting number. It was used on the 71 351CJ, and all 71-74 351C engines. It can be machined for 2 or 4 bolt mains.

"Better" is a subjective term, which depends on what you're looking for. The CC heads are the desirable head for most 351C guys, as most equate compression with power. OC heads produce great power too, and may flow better than a CC head due to less valve shrouding. The CC head has excellent "quench" if the short block is built properly, and can run quite a bit of compression on regular pump fuel.

Thank you so much for all that great information! I am learning slowly but surely.

 

[Hemikiller]

Some great reading at this link.

https://pantera.infopop.cc/topic/sticky-3-351c-basics-and-performance-tuning
Due to industry backlog, I would start the process of getting your camshaft and lifters secured. Flat tappet lifters have many issues right now, to the point I can't recommend using them. Talk to a cam company such as Schneider, Bullet, Lykins Motorsports or Howards for a recommendation on your engine. Stay away from the "rumpy-thumpy" cams like the Comp Cams Thumper and Howards Rattler series, they are literally the opposite of what a 351C will want.

 

[Stanglover]

Those are closed chamber heads, the same as I have on my Mach. Supposed 10.7:1 comp ratio according to Ford. Date codes are June (F) and July(G) 1970. I'd think they are very early GA heads. Previous 1970 heads were (N) heads and supposed to be 11:1 comp ratio, slightly higher.
Date code on your block should be just above the casting number. Here's a pic of mine.
Q, is it a 2 bolt or 4 bolt main? (or did I miss that ?)

 

[tpj71mach]

Some great reading at this link.

https://pantera.infopop.cc/topic/sticky-3-351c-basics-and-performance-tuning
Due to industry backlog, I would start the process of getting your camshaft and lifters secured. Flat tappet lifters have many issues right now, to the point I can't recommend using them. Talk to a cam company such as Schneider, Bullet, Lykins Motorsports or Howards for a recommendation on your engine. Stay away from the "rumpy-thumpy" cams like the Comp Cams Thumper and Howards Rattler series, they are literally the opposite of what a 351C will

Thanks for the information, that link has a lot for me to learn from about these engines.

 

[tpj71mach]

Those are closed chamber heads, the same as I have on my Mach. Supposed 10.7:1 comp ratio according to Ford. Date codes are June (F) and July(G) 1970. I'd think they are very early GA heads. Previous 1970 heads were (N) heads and supposed to be 11:1 comp ratio, slightly higher.
Date code on your block should be just above the casting number. Here's a pic of mine.
Q, is it a 2 bolt or 4 bolt main? (or did I miss that ?)

Thanks, for tie info, I honestly don't know if it is 2 or 4 bolt mains yet. I called my machine shop but they went home for the weekend already. I will call Monday and find out.

 

[DaveMT]

Pardon my ignorance, (I have just came over to Mustang after restoring a few Camaro's and Chevelles) but are these heads open chamber or closed chamber?

View attachment 63228

Those look like they are the later 66.1cc closed chamber heads.\ according to the D1AE-GA casting number. Those were the same head castings that were used on the 1971 Boss 351 motor except that the Boss 351 heads were modified with adjustable rocker arms, etc. for use with the mechanical cam and lifter arrangement on R-code motor.

 

[batwrangler]

Just below the driver's side cylinder head on the rear of the block. Use a mirror if the engine is still in the car.

The date code on your cylinder head (OM4) is Dec 4th, 1970 so you may have closed chamber heads.

 

[batwrangler]

My says 2L2C can you tell me what this means?

 

[Stanglover]

My says 2L2C can you tell me what this means?

I think if you look again that will be 2L20, 1972 November 20th

 

[Hemikiller]

MustangTek has a good rundown of the Ford date codes

http://www.mustangtek.com/FordDateDecoding.html

 

[batwrangler]

I think if you look again that will be 2L20, 1972 November 20th

looks to me clearly a "C" zoom in on it

 

[Stanglover]

looks to me clearly a "C" zoom in on it

Hmm, where exactly is that located? It's not a head number, but probably a part date code and shift. C would be third shift.
Head numbers are located between the valves, so you need to pull the valve cover to see them. Here's a fuzzy pic of one of mine, which is 0M1, i.e. 1970 Dec 1st.
To know hat heads exactly you have, then it gets tricky as the intake has to be pulled to see them and even then, you need a mirror and camera. Here's pics of mine, which are located under the intake runner on two of them, D1AE-GA

 

[batwrangler]

OK I just found these both (pic above) and this one found on driver rear block back side just below head

 

[Hemikiller]

looks to me clearly a "C" zoom in on it

That's not a casting date, it's a stamped date code for a variety of machining/assembly operations. There will be another on the pan rail by the oil pump.

 

[batwrangler]

Ok so its not a serial number wright ,,,and i dont know were the pan rail or the oil pump are ,,The car is still up on the lift so i can look at it anytime

 

[Hemikiller]

The stamping on the back of the block below the head is the Federally mandated partial VIN number. First number is hard to read, but it looks like a 3.

3H531664

3 - 1973 model year
H - Lorain, OH assembly plant
531664 - 31,664th Mercury serialized

Lorain built the intermediate Torino/Ranchero/Montego platform in 1973, so the engine would have came out of a Montego

 

[batwrangler]

My vin is Q and the last 6 numbers are different

 

[batwrangler]

it is a 3,,so does this mean i don't have a numbers matching motor ? ok i reread your other post motor came from another car ,,,Thanks This is great news at least now i know thanks again