# 66 engine code question



## alanderson (Sep 8, 2014)

I purchased a 66 lemans that looks to be 100% original/numbers matching,however i'm coming with an engine code on the right side under the head that shows a # 20123 with the letters XS underneath the #'s-i can't find that code for that year,car also has a Gto hood and grill,but the 237 vin#,can anybody clarify?


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## Roger that (Feb 6, 2010)

The 237 series is the Pontiac LeMans, should not have the GTO hood or grille. The XS code was used on many engines throughout the years. That code was used in 1966 as a 389 tri-pwr with RAM air. That engine would not come with the LeMans. The code XS was also used on other various years with the 400 cid engine and the 350 cid as well.

The 20123 is the engine unit number. If you have the protect-o-plate for the car that number will be located on the plate and shows the engine unit number and engine code that was born to your car.

You need to find some more numbers on your engine such as the casting codes which could be on the rear of the engine near the distributor or later years was found on the rear passenger side of the block below the head. A date code would be needed as well which is also on the distributor pad.


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## alanderson (Sep 8, 2014)

I'll check for more codes tonight.Are you talking about the cowl tag with a engine code on it?As far as the carb...it is a holley,on a manifold i have not seen,its all open underneath it with a sort of sheet metal pan a couple inches under it.


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## Roger that (Feb 6, 2010)

No, the protect-o-plate was given to the original owner and was to be attached to the back of the Owner's protection plan booklet. The plate(s) changed throughout the years but here is one for the 1965 model year.

Holley was not a factory Pontiac carb.


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