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The official club for enthusiasts of the

1970 & 1971 Oldsmobile Cutlass Supreme SX


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Terry Divelbliss
Club President

Alan Reedy
Senior Tech Advisor
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Bob Peters
Founding President


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Olds Rants & Raves

Cutlass Supreme with 455
Author Last Post
Here are the pics - 70 Olds Cutlass 455 - found the original 350HC (L74) that would have come originally with car - so I have the best of both.

Terry- working on pics-couple of question s
-was the HC350 -QN- only available in 1970? can i still be a member if i have a clone?Did a ll 70 cutlasses have the bolt hole for the front fender support?- The neat thing with this car is it was 891 of 68000 produced-hope the pics help-will follow shortly-Ted
Hi Ted, can you post or email me a pic of your car? I have a handful of '70 Supremes in the "registry files" that have 455s but are not SXes. Owners at the time of sale (Ebay, traderonline, etc.) claimed that they were original #s matching 455 cars, but who knows. Maybe yours is one of the gold ones I have and i can I can take one off the list. Thanks -

Just wanted to let you know my conclusion. I've determined the car is a 1970 Olds Cutlass Supreme that was ordered with the L74 engine package - it came with a 350 HC V8 4bbl that had dual exhaust and was ordered with options that were also available on the SX. At some point in the car's history - earlier I suspect - a period 455 replaced the 350 and voila a SX clone was born. The car's frame and running gear's in great shape and it runs and drives perfectly. Based on this, I'm going to start to restore a car I wish I had in high school.

If anyone needs codes the were available on the Cutlas on 1970, let me know because I have the original build sheet from the Freemont plant.

thanks bob ill keep you posted on my reasearch

ted bowles
All Cutlass SX cars were build with a 455. You could get a Cutlass Supreme with a 350 and just about every option found on an SX. It seems like you have a very nice car that was cloned into an SX.

Bob Peters
SX455 Club President
Joined to find out whether my Cutlass Supremem was a SX. Wanted to share. Found original build sheet under gas tank. Car originally came with L74 (350 4bbl) with a whole lot of options..

Were certain options exclusive to the SX only? ie A31 - power windows? N30 - delux steering wheel

The motor it has in it now - does not match the car - but the block unit number -39X1224A8 tells me it"s a 455 built in 1969 in Kansas City. The block date and the head date are built within 4 days of each other in November of that year. Has factory dual exhaust and OC69TH400 transmission. Car was built Aug 9 1969.

Is this car a cloned SX or an Olds Cutlass Supreme with a 455-400 transmission with some options?

Your feedback is appreciated. Thanks Ted   PS vin # is 342570Z100891 2 door hard top one color - was gold
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