Hey Guys,

I have a 70 Cutlass I've been working on for a few years, and have never been able to figure out if it is a legit SX or not, hopefully I can get some feedback

When I bought the car, the body / interior was in good shape, but under the hood looked like it had not been touched.. in many many years. Lots of rust scale etc, I'll try to attach a picture

Car has a 455, and had a 2bbl carb when I got it (which seems consistent with many 70 SX's). After removing all of the accessories to detail the engine, I was able to get a the stamp pad and clean it off (lots of rust scale)... The engine block # matches my vin number, but the engine number is stamped twice on the block, kind of offset.

The only Cutlass-vin code 70's that would have a factory 455 would be an SX... right?

Anyone heard of a double-stamped number on a block?

Of course, no build sheets with the car, none under the seats or over the tank... Car has dual exhaust w/bumper cut outs (easily added)... not the original trans so thats no help...

If these attachments work, one shows the engine before I cleaned it up + the layout, and one shows the vin stamp pad

Any thoughts would be appreaciated!

Thx - Dan

IMGP6335.jpg

EngineVin#2.jpg

IMG_7171.jpg

 

I believe the 455 2bbl was available in any Cutlass model. I remember driving a 70 Cutllass S holiday coupe with an original 455-2 many years ago.

The double stamp isn't all that unusual. Ive seen them before. Pretty sure DaveH had some recollection of the way they were stamped causing that to happen occasionally.

 

I actually have the 70s SX with a 2bbl coupe. One not is the extra fender brace that is only located on the coupe.

Here is a picture of what I'm talking about. If you take off the fender, you should be able to see the brace, if not, just check for the brace.


Of course, see if you have the side badging. You should have the SX just under the 2nd S of Cutlass. There is more information at sx455.com

 

Thanks Joffroi. The car is a convertible - do those have the braces you mention?

The car was cloned to a 442 by previous owner (its the blue car in the orig post) so no SX badges to look for. Previous owner indicated he was familiar with the car locally (as an sx badged cutlass) in michagen for about 10 years before he bought it in 2000, and as it needed paint... so he went the 442 route. He did not know if it had the original engine, that was some digging I did.

Might just be an unsolvable mystery w/o paperwork

 

Thanks Copper128. My car is a convertible.. so there were big block Cutlass drop tops in 1970 that weren't SX's? I've seen them advertised on few occasions - convert cutlass with a 455 as original engine, but I always thought that was an uninformed seller...

 

convertibles do not have the braces. This is going to be tough for you to find, I would maybe ask the president of sx455.com for help here.

 

Thanks Joffroi, I dropped him an e-mail, hopefully I'll hear back....

 

Cutlass in '70 could have the L-33 455 2bbl, Cutlass S could have the L-33, Supreme could have Y-79 (SX) 455-2bbl(which included the L-33, L-31), W-32 455-4bbl, L-33, and I believe the L-31 455...

 

Also, if you can get the inner fenders out, look to see if the holes have been filled on the fenders where the SX badge would be...this wouldn't prove either way, but could help answer your question about it's authenticity!

 

I know everyone has always said that the convertibles do not have the brace but mine does. when I got the car (28 years ago) the car had never been apart and had only had one real crappy repaint. from what I know of the car it was all original when I got it and that was back before anyone knew what they were. in '82 when I got it it was just a used car. it is an early build and was a 2 bbl car also.

 

Thanks. No braces on mine, just an empty hole....

 

Great idea... I took a look w/ a flashlight through the door jamb with the door partly open at the inside of the fenders where the SX emblem holes would have been and saw... patch panels - both sides... oh well!

 

Thanks for the info... Mine is for sure a factory L-33. What differences would there be between an L-33 convertible and an L-33 SX Convertible....? (I know, hope to hear back from SX455)

Any ideas on production #'s of non-SX 455 Cutlasses in 70? SX455 says 793 SX convertibles...

 

Got a reply back from SX455, indicating that this car is in fact an SX based on the matching VIN L-33 in a Supreme conv and build date. Thanks for the help + comments

Still curious if anyone knows production #'s for Cutlasses in '70 with the 455 (L-31 or L-33) outside of the SX - seems like these would be sought-after big blocks

 

Something does not sound right here. A VIN matching L33 simply means your car must be dated prior to March 1970 when the L33 was canceled. But the L33 was available in Cutlass Supreme Convertibles other than those with the SX option too.
So where does that conclusion come from?

And yes, I have recently obtained some more production figures on the 455 engine usage in '70, and will make those figures available when I get a chance to compile them.

 

I have been sporadically building the registry photo album for the SX455.com site since it was established, and I collected pics, info, and for sale/auction listings for years before that. I have found 2 or 3 1970 Supreme hardtops that were L-33s but not Y-79 SXes in all that time. I haven't found any ragtops so far, but they could be out there. Kurt's numbers showed that slightly more L-33 equipped convertibles were built than the reported 793 Y-79 convertibles in 1970, so it appears that there are a few non-SX ones out there. Not many though - I've been hunting these for over a decade and I haven't found a proven one yet.
Terry

 

Kurt / Terry - Thanks for the feedback

I agree I'm not totally convinced with the conclusion drawn, and responded last night to Bob @ sx455 with a clarification - what would distinguish this car as an SX versus an L-33 equipped Supreme conv

From a practical standpoint, I'm pretty sure it's an SX, as the seller I bought it from in 2007 - who was straight shooting guy almost to a fault - indicated he had been familiar with the car around town sporting SX badges over it's original paint for about 10 years before he bought it.

But it would be nice to definitively authenticate it one way or the other - I'm content with a factory big block either way - just would like to get my story straight at the local show and shine or at the gas pump

It seems to me that short of a finding a build sheet - which apparently don't show up much in Lansing cars.. or other historical info / proof, there is no way get a bulletproof conclusion. But I'll keep you posted if I learn more, and appreciate the various feedback! - Dan

 

Dan, you are being as realistic as possible. "It is what it is" and being a factory big block is certainly cool enough, regardless. And there is nothing wrong with a "probably is" being the best answer you can come up with. Sometimes the "facts" can provide enough evidence, sometime they can't. But its nice to find out everything we can.
Personally, I feel when you have a "probably is", go ahead and badge it up as such, enjoy it, and have the honest answer ready for when asked. With no apologies.

 

I mentioned it before but growing up in NJ, I knew a kid who's father had since new a 70 Cutlass conv 455-2 barrell that was not an SX. I drove in it a couple times and remember no badges and it had dual exhaust but no cutout bumper. Orange with black interior. So, I know they exist. I think the only firm rule in 70 was that a 455-4 barrell had to be an SX or a 442 but the 2 barrell could be had in a regular cutlass

 

Does the car have boxed control arms and anti-sway bar on the rear? I've heard that the SX has the same suspension as 442. ( I think I remember the sway bar on my SX some 35 years ago. ) I would prefer to have the SX over the 442 as they are rarer and less well known. Chumley

 

Boxed lower control arms and sway bar were optional, not required on the SX.
Terry

 

So could the rear sway bar be ordered without the boxed lower control arms,
or were they sold as a package deal?

 

They were engineered and installed together. Without the boxed arms, the sway bar would be useless since the walls of the open control arms would flex.

 

I think one of the more important things to know about the SX (in 1970 when it was introduced) was that what Olds was offering was a thinly veiled way to buy a 442 and dodge the higher insurance costs that came with the known high performance monikers. Buy a Cutlass Supreme, check off the Y79 (SX pkg), W32 (the same engine as the 442), and FE2 (the 442 suspension), and voila! you have a 442 without the badges and the higher insurance costs! Also some sleeper appeal there too.

Furthermore, it more than just flexing. Without boxing the arms, the arms can eventually crack then actually break making for a dangerous situation.
BL? *Never* attach a sway bar without boxed arms.

 

Was Y79 stamped on the frame anywhere on the SX's? I heard many years ago that it was, but never had it confirmed as a fact. Back in 1977 when I was in an accident with my SX, the insurance agent asked "does this have a 455"?....no! it's just a 350.

 

No, just a nasty rumor. Doesn't even make sense that it would, why in the world would it be?

 

"They were engineered and installed together. Without the boxed arms, the sway bar would be useless since the walls of the open control arms would flex."

This is good information to have, last year i came across an original rear sway bar, and installed it with my original lower control arms. It looks like I either need to go pick up the lower control arms off that car or add the boxing tabs. Does anyone know who sells just the boxing tabs?

 

Chumley - my car did not originally come with boxed rear control arms (it has them + sway bar now). Sounds like from the commentary that rear suspension doesn't define an SX either.

I asked but never got any further response from SX455 about how to distinguish an SX from a L-33 optioned Cutlass... so I'm still stuck at the "probably is" an SX as Kurt so well defined the reality of documenting these cars.... - Dan