1968 383 engine stampings

[smithchargers]

The engine in question is the original engine for a 1968 Plymouth roadrunner. It has the faint stamping on the bell housing area of the engine that match the last eight digits of the vin to the car. The stampings pictured are on the bottom of the engine block near the bell housing of the transmission. Can anyone shed light on what these numbers correlate to exactly.

 

[1KoolBee]

P=Premium fuel, T=Trenton plant . H=Hp? Numbers should match vin. Normally stamped at top of bell housing.

 

[smithchargers]

P=Premium fuel, T=Trenton plant . H=Hp? Numbers should match vin. Normally stamped at top of bell housing.

The numbers do match the vin on the top side of the bellhousing area like I described. The picture shown is on the very bottom of the engine near the back of the oil pan

 

[1KoolBee]

Do at least some of the numbers (Julian Date?) line up with assembly date stamped in front of right head?

 

[smithchargers]

There is no stampings left on the pad below the distributor as it appears that the block has been decked. Are you that the long numbers pictured are Julian numbers?

 

[1KoolBee]

Not sure, just my guess is that part of those are assembly date and maybe shift. I’ll check one of my decoding books when I get home

 

[R/T Boy 67]

2422 is the 10,000 day calendar date Mar. 15th 1968.

 

[smithchargers]

The casting date of the block is 2/27/68 and the car was built 3/19/68 so that lines up

 

[rickseeman]

In the numbers I have "H" means standard 4-bbl

 

[rickseeman]

Maybe it has air conditioning

 

[rickseeman]

What I'm trying to say is if it had a/c then maybe that "H" means standard 4-bbl because they were a hair lower hp where as with no air would have been stamped HP because of 335 hp? I'm no expert. I don't even know if a/c was an option on a 68 RR.

 

[oldkimmer]

Was it not that Plymouth had 330 hp and Dodge had 335 hp? Or am I thinking wrong? Kim

 

[RemCharger]

Was it not that Plymouth had 330 hp and Dodge had 335 hp? Or am I thinking wrong? Kim

The SB and the RR had 335hp unless you got A/C, then 330hp

 

[Chi Town Runner]

P= Premium Fuel
T = Trenton plant
383 = 383ci
H = 383ci 4bbl V-8
2422 = 15 March 68
1775 = ?????

Just my .02c

 

[Chi Town Runner]

I sent you a PM

 

[R/T Boy 67]

1775 is a daily sequential number.

 

[1KoolBee]

P= Premium Fuel
T = Trenton plant
383 = 383ci
H = 383ci 4bbl V-8
2422 = 15 March 68
1775 = ?????

Just my .02c

1775 = sequence in that production run, in other words, 1775th engine in that production run. FYI, my Bee has air and the 330 horse motor. No “H” in the production number stampings, so I’m sticking by the H=HP . The stamping in front of the right head would have had HP instead of just H.

 

[Chi Town Runner]

In 68 model, if 5th digit of the VIN was "H" it was for 383 ci, engine, whether it was 330 HP or 335 HP
Your correct that if it was 335 HP there would be an HP stamp on the block after assembly of the engine
And in 68 the only vehicles that got the 335 HP engine were Road Runners and Super Bees.
There was nothing different in a bare block 383 engine as cast,

When the 383 blocks were cast, the foundry did not know if that 383 ci engine was going to be 330 hp or 335 hp and that's when the "PT" numbers were stamped'