1966 GTO engine casting numbers...
 

My father recently acquired a 1966 GTO convertible. Car seems very original, but a few things have me scratching my head.

From what I have found online, it should have an WT or XT stamped block. It has YE stamped under the passenger side head. Kind of a bummer, the car has 83K documented miles. Maybe it puked the engine years ago and the short block was replaced with one form a passenger car? The heads are 093's, intake manifold is 9782896. The alternator is an 1100705 (37A), supposed to be a 1100704? The water pump is a 9782482, unable to see the date code. A source I found online says a 66' should have a # 9793130 water pump?

Just trying to nail down exact part numbers so when I pull it apart to replace some seals and repaint the engine - I can reinstall the proper parts. It runs well, no sludge evident inside the engine. No smoke, and no unusual noises.

Thanks in advance. :usa2:

Check out www.wallaceracing.com for the codes.
On the block behind the distributor you should find the casted code and date code for the block.

Is it a factory 4bbl or factory TriPower -
factory automatic or manual -
California sold new - or 49 state sold new -

Lots of different codes for the different applications.

A 1966 YE is a Big Car 389 4bbl with Automatic Trans.
it would have had 092 heads.

093 heads are correct for 1966 GTO 4bbl and 3x2
and 421 with 3x2.

YE code was used in many different years - need to get the date code from the block.

When I bought my 66 from a guy in Atlanta in 1990, I had him send me a photo of the back of the block near the distributor to confirm the block casting # and the build date of the block vs. the body. That check out so that's when I actually went to look at the car. Those cast dates are probably the most important number on a motor, the numbers on front (WT YC ,etc) can be restamped to what ever you want the motor to be by any unreputable machine shop.

I'll see if I can get a good look at the casting behind the distributor. Someone along the way has installed an HEI. :mad: (Yet they were so lazy that the factory coil & bracket are still there)

The car is factory 389 4bbl, 3 speed manual, manual brakes and steering, gauges w/ tach, convertible, Rally I wheels, not much else.

I use to stick my small digital camera or cellphone in and fire of a couple of shots. The flash helps to show the digits better if aint to dirty.