Is there an easy way to tell if you have the high or low compression 330ci? It came with a Quadrajet and a Jetaway 2pd.

Thanks,
George

 

i believe the 330 in 66 was high compression (10:25 : 1 ) on the 4 barrel intake applications...
2 barrel had a lower compression ratio (9:1)




V8 - 330 2-BBL250 @ 4800335 @ 2800 (bore x stroke) 49.63.938 x 3.385 CR 9:135
V8 - 330 4-BBL320 @ 5200360 @ 3600 (bore x stroke) 49.63.938 x 3.385 CR 10.25:135

 

im sure the heads were the same size, but the pistons are the difference,cam may be different as well i think

 

im sure the heads were the same size, but the pistons are the difference,cam may be different as well i think, by the way your avatar is creepy.

 

Lol, I'm sure the old school guys can tell you what that avatar is from. This will be a good trivia question. Circa 1971

Thanks for the info all.

 

easy way to tell?
try to run it with low octane gas .
My '67 330 high compression cutlass only likes 93 octane.

 

o ive seen clockwork orange many years ago, twisted stanley kubrick. its still creepy looking lol

 

Would you rather he replaced it with a Barney avatar?
THAT WOULD BE CREEPY HERE!!!
Jim

 

better yet run his avatar on barneys web site

 

I've felt the same way ever since I saw that avatar. It was creepy then and it still is.

 

Wow, tough crowd

 

Yea, I went to high school with a guy that looked just like your avatar. YES... he was creepy! I do remember Clockwork Orange... strange stuff for sure!

Sooo... back to the OP. There should be a W stamped on the head after the numbers. I think that's suppose to indicate a high compression 330?

 

I know it doesn't like low octane fuel so I'll look for that 'W' tomorrow.

 

HC would have an orange/red air cleaner and gas cap would say premium fuel only if the original ones are still there with car.

 

Good to know, thanks. My AC is red/orange and I think gas cap is original. I'll check tomorrow. Out of curiosity what color AC is the low compression one?

 

Low Compression would have come with a black air cleaner.

 

The low compression ones were black, and if im not mistaken they use a different, smaller housing that has a longer, thinner and more rounded snorkel.

 

To correct myself... there should be a G at the end of the stamped pad on the passenger side head.

 

Just checked the heads and they do indeed have a 'G' stamped on them. The gas cap also says 'Important Use Premium Fuel Only' I appreciate all the good information everyone. I'm happy I have the high compression engine but it just seems sluggish to me. I guess I'll have to fix that with the big block and the Tri-Carb setup

Thanks,
George

 

Now your talking!!!!!!!!!!!

 

theres also the forced induction option ...

 

So what does the W indicate? I have "W" and am curious if I have a High Compression engine

 

Page 05 of the Chassis Service Manual tells you what the engine unit numbers mean. Available free of charge at Wild About Cars:
http://wildaboutcarsonline.com/cgi-b...aldisplayed=50

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Check and make sure the transmission switch pitch function is working correctly. If it's not it can be a real dog. Engine timing is also very important. Also ensure your throttle linkage is opening the carb all the way at WOT.

 

I saw that movie when it first came out, it was weird and creepy then but compared to todays crap it's pretty mild, I have it in my DVD collection.
I always think of Clockwork when I hear Ludwig Van.

 

high compression heads for 66-67 will have a stamp starting with W, then production#, then end in G.

 

...no offense, that avatar/picture is kinda dumb! Lol get a nice picture of an olds, or a nice set of *****/butts

 

😃

 

[QUOTE=67cutlassguy;1055972]...no offense, that avatar/picture is kinda creepy Lol get a nice picture of an olds, or a nice set of *****/butts

 

If your still following this thread, the "W" on the head stamp should mean its a 330 engine followed by numbers then a "G" or "L" (low compression) hope this helps you out.

 

Yup, still following. The engine is sitting in my garage as I restore the car. It's for sale too.