Identifying Longchamp Cylinder Heads

the hand stamped number is likely DeTomaso if the engine is original to the car, does it correspond to the VIN?

the clock, even experts can't agree on what it means

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

and the cylinder head casting date code, am i reading 5M9 correctly?

The true head casting is actually on the underside, reach out to other Longchamp owners to compare engine VIN (location, font, style)

EDIT *******  upon reflection and closer examination, you may have a 1972 LTD motor short VIN 2P*10541 with 1975 or 1985 heads. ******

I found a single reference to DT engine VIN. so will need another to confirm OE. Check your intake

The DT OE stamp should match your VIN plate

The last production 351C engines (both 2V and 4V versions) were assembled in the US circa June 1974. 351C engines with 4V cylinder heads were never assembled in Australia. Australian heads do not have a "2" or a "4" cast in their corners.

4-dot cylinder heads were cast in the US for M code engines manufactured from July 1970 through June 1971 (D1AE head castings), and Q code engines manufactured from July 1971 through June 1974 (D1ZE and D3ZE head castings). However there was an extra run of D1AE-GA head castings produced for the NASCAR teams in about the time frame of 1975/1976, the same time frame in which the first batch of Australian sourced NASCAR blocks were also manufactured. A 4-dot head with a December 1975 casting date would almost certainly be one of those D1AE-GA castings, having 66cc quench combustion chambers.

Heads from this batch of castings were not installed on any production engine, thus these heads were added to this short block after the fact; no doubt the short block was originally equipped with open chamber heads.

Many thanks. It's a 1975 Longchamp. I'll chack if the  block is D1AE-GA . what's the difference between these heads and regular production ones?

D1AE-GA is the casting number of the heads, not the block. The casting number of the block is most likely D2AE-CA.

There are no differences between these heads and the earlier versions cast from July 1970 through June 1971. They were machined for adjustable valve train (studs & guide plates, plus spring cups) the same as production Boss 351 heads.

denisc posted:

The true head casting is actually on the underside, reach out to other Longchamp owners to compare engine VIN (location, font, style)

 

 

EDIT *******  upon reflection and closer examination, you may have a 1972 LTD motor short VIN 2P*10541 with 1975 or 1985 heads. ******

I found a single reference to DT engine VIN. so will need another to confirm OE. Check your intake

The DT OE stamp should match your VIN plate

 

 

 

Thanks Denis, the engine stamp numbers and letters "CMD 074" is from my 1973 Deauville. Longchamp has 351/1057

George P posted:

D1AE-GA is the casting number of the heads, not the block. The casting number of the block is most likely D2AE-CA.

There are no differences between these heads and the earlier versions cast from July 1970 through June 1971. They were machined for adjustable valve train (studs & guide plates, plus spring cups) the same as production Boss 351 heads.

George P posted:

D1AE-GA is the casting number of the heads, not the block. The casting number of the block is most likely D2AE-CA.

There are no differences between these heads and the earlier versions cast from July 1970 through June 1971. They were machined for adjustable valve train (studs & guide plates, plus spring cups) the same as production Boss 351 heads.

Indeed is D2AE-CA. what does this tell us about the engine?

D2AE-CA

D = the decade made "70's"
2 = year produced
A = Full size Ford 
E = engine part

also seen in your picture

1G9

1= 1971

G= July

9= 9th day of month,

therefore block was cast 9/jul/1971

denisc posted:

D2AE-CA

D = the decade made "70's"
2 = year produced
A = Full size Ford 
E = engine part

also seen in your picture

1G9

1= 1971

G= July

9= 9th day of month,

therefore block was cast 9/jul/1971

 

thank you all!