engine and drivetrain 121 head what cars?

[Livio]

don"t scream at me folks this topic might have been posted before

My car is a 72 2002 but it has the 121 head, from doing my search I should not have that head unless it was swapped by previous owner.

any block numbers or casting I could look for to verify if the engine has been swapped or just the head.

Livio

[Scott Sislane]

121 Cylinder head:

8.5:1 CR U.S. "Spec" piston on 1968-1972 2002's

42.3 mm pin-to-deck, flat top

9.0:1 CR U.S. "Spec" piston used on '72 US-model 2002tii's

9.3:1 CR European 2002TI (twin-carb model)

42.1 pin-to-deck, 5.2mm dome

10:1 CR Early euro-spec 2002tii

42.5 mm pin-to-deck, 4.4 mm dome

E12 Head:

6.9:1 CR Factory "Turbo" pistons (used on 1974 2002 Turbo)

42.0 mm pin-to-deck, 3.7mm dish

8.1:1 CR flat-topped piston (much like the 8.5:1 CR used on the

121 heads) used on '75 US-model 2002's, also on most

US-model 3-liter cars of the era. (keep in mind that

the 2-liter 4-cylinder with the E12 head and 3-liter

6-cylinder cars can interchange pistons)

8.3:1 CR U.S. "Spec" piston on mid 1972-1974 cars

9.0:1 CR U.S. tii pistons

9.5:1 CR European tii pistons

E21 2.0 Head:

8.3:1 CR flat-topped pistons (used on 49-state '76 2002's,

US 2-liter 320i's)

9.3:1 CR domed pistons (used on european 4-cylinder 320i's

[Napes]

I have read, and it's been stated on this blog before, that the 49-state '76 2002's with automatic trannies had a higher CR that the manual equiped cars to compensate for running 3 gears (in the auto) vs: 4 in the manuals.

Do you have any info on this? If the CR was higher was it done with different pistons in that the '76 automatics still had the same E21 head?

Liked the info you posted on the various heads. Thanks.

Bob Napier

[Mike Self]

the 1 bbl Solex was ditched in favor of the two barrel, in late 1972. Most 72s orginally had the 1 Barrel setup, but many have been converted to a two barrel manifold with a Weber 32/36 or 38/38.

RealOEM or a factory parts book will give you the actual changeover VIN.

cheers

mike

[Scott Sislane]

Bob, I just pulled those details from this page:

http://www.bimmers.com/02/faq/engine.html

Scott

[Bill_Riblett]

the 1 bbl Solex was ditched in favor of the two barrel, in late 1972. Most 72s orginally had the 1 Barrel setup, but many have been converted to a two barrel manifold with a Weber 32/36 or 38/38.

RealOEM or a factory parts book will give you the actual changeover VIN.

cheers

mike

The change to E12 heads was at 258 3465 for 4 speeds and 253 2752 for automatics according to the factory parts books.

For US 2002tiis, I'm confused as BMW shows 3 different VINs!

276 1944

276 2014

276 2372

[jgerock]

The tii engine I have # 2762332 has a 121 head - assuming it is the original.

[c.d.iesel]

WHAT IS THE MOTOR NUMBER STAMPED ON THE BLOCK?

(IT'S NEXT TO THE STARTER MOTOR/TIMING INSPECTION HOLE?)

THAT NUMBER SHOULD MATCH THE NUMBER ON

YOUR STEERING COLUMN,

AND ON THE PASSENGER SIDE INNER FENDER

[TobyB]

many '72's had 121 heads...

t

[c.d.iesel]

......." I should not have that head

unless it was swapped by previous owner

any block numbers or casting I could look

for to verify if the engine has been

swapped or just the head................."?

we don't know the block serial # yet? -

and when we do?

then we'll know what head should be with that block?

Livio ? are you there ?

can you respond ??

[Livio]

engine number is 2640793 my vin is 2579308