Folks, I just picked up a 67' convertible. Trying to determine what engine block I have.

PHS states that car was originally a 326 w/2BBL /muncie 4-speed. But I believe that I have a 400 ci engine likely from GTO.

The original owner (over thirty years ago) appears to have attempted to create a 400 clone - by swapping in a 400 ci engine, hood (where they discarded original option hood tach), grill (with hockey stick) and front bumper (with arrow head emblem).

The engine code (photo attached) appears to be 677398 VT (or WT). The dilemma is that the engine code (677398 VT or WT) appears to be altered or just damaged. The Rochester QuadraJet carb (R4-4MV) #7037262 is a 4BBL for the 67' GTO 400 w/manual transmission.

Any guidance on how to confirm my hypothesis of a 67" GTO 400 ci engine block, manifold and carb being swapped in?

Is there a date code in the casting by the dis pad? Or the number of the year itself (69 and newer) Can you see a cubic inch casting number on side of the block? (71 and newer) Just a thought.
PS. What heads do you have?

You need the block casting number and the two letter code to zero it in. The casting number is on the block at the rear of the passenger side head for mid 67 and later and on the distributor pad for early 67 and older.


Block casting numbers:
http://www.teufert.net/pontiac/bloccast.htm

Two letter engine codes
http://www.teufert.net/pontiac/engcodes.htm

The number near the two letter code in your pic is the unit number which won't do you any good.

The two letter code looks like YT which shows up several times as a 400 for 68, 69, and 72. Probably not damage, just sloppy with the stamping.

A lot of good info here too:

http://wallaceracing.com/

BTW, your car was originally my car's twin. 67 vert 326 2bbl Muncie hood tach

Thanks Bob. I have determined the following:

Carb - Rochester QuadraJet (R4-4MV, #7037262) for 67" Pontiac GTO 400 ci w/4-speed
Manifold - GM #9786286 for 67' Pontiac GTO 400 ci
Heads - GM Pontiac #670 for 67' Pontiac GTO 400 ci

I am unable to see the stamps on distributor pad nor back of engine block (next to firewall) at present.

The mystery of the block remains - should the actual stamp be YT (vs. possible WT) this means block was a 67' Firebird block or a 72' GTO block (as GTOs did not have YT codes prior to 72' as best as I can tell). The net is I'll be happy if the block is either a 67' Firebird YT or 67" GTO WT - but the later year GTO YT block hp ratings are poor.

Any suggestions on how to get visibility to the stamps on distributor pad and/or back of block w/out removing engine block?

You can stick your phone in close and take a pic.

Spray it down good with some carb cleaner and compressed air. Wipe the gunk out as best you can. Then pull the distributor and you should be able to see the date code. You may need some sort of mirror to see the engine number behind the pass head.

Firebob, you are just across the Bay from Sscott. You should run over there and scope it out. Sounds like a great 'bird!

Think I deciphered the code!

The casting code on distributor pad ("F147") which represents block build of June 14, 1967 - appeared after much carb cleaner and scrubbing.

This casting code plus cowl tag confirming V8, engine code confirming 400, and carb, manifold and head stamps designating 67' Pontiac GTO 400 /4-speed completes the story. Not a true numbers matching car (relative to the he "brain" but the replacement engine is period correct and higher performance and the trans and axle are original.

The brain configuration plus the 400 hood, bumper, grill and cool options such as; muncie 4-speed, hood mounted tachometer, rally gauge cluster, ride-and-handling package, safe-t-track, shoulder belts, dual exhaust, traction bars and cocktail shakers make this an interesting car even if not true numbers matching brain - and the fact that it is true CA car with second /most recent owner having it in his barn for past 30 years makes for an interesting story.

Assume original owner swapped a period correct 67' GTO 400 ci into the car in the late 60s or early 70s but have no idea why. The car was delivered to Jim White Pontiac in Santa Monica in 67' and this dealership is no longer in business so no way to track down the original buyer /first owner.

Thanks for all the advice Guys - very helpful. I learn more every car I buy.

Sean,

Not sure you have the correct info. I always check Wallace racing and use the head code and engine code and then confirm there is a 67 Firebird with a YT code.

Here is what Wallace finds:

Year Engine HP Engine code Trans CR Cam Head Code BBL Carb No. Misc
1967 400 325 HP YT A 10.75 067 670 1-4 7027272 Block Casting # 9786133

The engine code is YT,
the engine unit no is 677398. You compare this no. the engine unit no. identified in your PHS docs.

If you have 677398 in your PHS docs you are num matching on engine at the very least..

Hope this helps.

1967 Engine Identification Codes
Code Cyl. Disp. H.P. C.R. Carb. Trans. Description Qty. Built
WI 8 400 325 10.75:1 4 BC Man. Firebird 400 Ram Air
WC 8 326 250 9.2:1 2 BC Man. Firebird 326
WH 8 326 250 9.2:1 2 BC Man. Firebird 3261
WK 8 326 285 10.5:1 4 BC Man. Firebird H.O.
WO 8 326 285 10.5:1 4 BC Man. Firebird H.O.1
WQ 8 400 325 10.75:1 4 BC Man. Firebird 400 Ram Air1
WU 8 400 325 10.75:1 4 BC Man. Firebird 4001
WZ 8 400 325 10.75:1 4 BC Man. Firebird 400
XI 8 326 250 9.2:1 2 BC Auto. Firebird 3261
XN 8 400 325 10.75:1 4 BC Auto. Firebird 400 Ram Air
XO 8 326 285 10.5:1 4 BC Auto. Firebird H.O.1
YJ 8 326 250 9.2:1 2 BC Auto. Firebird 326
YM 8 326 285 10.5:1 4 BC Auto. Firebird H.O.
YT 8 400 325 10.75:1 4 BC Auto. Firebird 400
ZD 6 230 215 10.5:1 4 BC 3-spd/Man. Firebird Sprint
ZE 6 230 215 10.5:1 4 BC Auto. Firebird Sprint
ZK 6 230 165 9.0:1 1 BC 3-spd/Man. Firebird Standard
ZN 6 230 165 9.0:1 1 BC Auto. Firebird Standard
Engine Identification

V-8: Find code stamped on the block in front of the right bank of cylinders.

6-Cylinder: Find code stamped on cylinder head contact surface of the block behind the oil filler pipe.

123456 = Production Number
WC = Engine Code
1 Air
Note: Conflicting information for following codes. One source lists them available but have not been able to confirm with other sources: ZF, ZG, ZL, ZM, ZR, ZS.

Thanks for this additional information.

The PHS confirms that car was originally 326 w/ muncie 4-speed. Engine unit code on manifest is 418020. I questioned this at first but have accepted PHS report as the bible.

The engine block, heads, manifold and carb stamps /codes all sync with 67" Pontiac GTO 400 (w/4-speed) - and thus are not #s matching car relative to the brain. The transmission and axle however are original - as well as most of the other components and options in car as best as I can tell.

In the end I am happy with this conclusion as I actually prefer the 400 /4-speed configuration over original 326 /4-speed configuration. I remain a bit perplexed on why /when engine swap occurred but doubt I'll ever know how to answer these questions.

I am taking car into mechanic this week and will try to get additional code off back of engine block near firewall to reconfirm my assumption above.