I have a 1966 Cutlass with a 330-4BBL. The code is W21G725L. It has a red air cleaner. I would think it is a high compression engine. I understand the suffix would indicate it is low compression but the G would indicate high compression. Any ideas out there?

 

I was just looking in my reference for 1966 Cutlass/442/WMachines and I cannot find a code like what you're listing. When you say you have this code, is it on the engine stamping pad or is it part of the cowl tag. The 66 400 cu/in engine is supposed to have a prefix code of V followed by a 6 digit number.

 

... Except he said he had a 330, Allan .

The chart says there is no such code as W21G725L.

BUT, if we assume that the G is really a 6, then it's W216725L, which is a real number, and corresponds to a 1966 "Low Compression Domestic L-73 Option" 330 with a 4bbl carb. and a 9:1 compression ratio. L for "Low Compression."
Sorry, not a high compression motor (at least not when it was made).



- Eric

 

Thx Eric,
About 1/2 hour after I posted that I realized my error. I also found the info actually in my VIN decoder under the engine code section. The part about G=6 makes it work, great detective work there. That was the part that I didn't get at all.