I bought a 1970 Cutlass years ago that was badged as an SX and I have always wondered if it truely was an SX or not. It didn't have the origonal engine, but looked like it was generaly untouched for many years and had the SX badges, a TH400 trans, a 442 bumper, a possi rear, bucket seats.

I still have the car and I put a 455 motor and 4.11 posi in it.

 

Years ago, the SX was totally under the radar and I doubt you'd have seen a clone. That crap only started in the last few years, after 442 pricing went thru the roof and some auction company or "investor" realised that hey, they didn't build many of these and we might be able to play that to our advantage.

A Supreme body with notch bumper, THM400 and SX badging that has been in your possession more than 15 years is more than likely a real SX.

 

I'm also curious about the SX designation.

Wasn't the SX a stand alone year (1970)? I've often wondered what the SX stood for, and if it was available only on the CS? I don't believe the SX was a 442, wasn't it a stand alone designation?

C'mon all you SX experts!! Help us out on this one. I don't feel like looking it up right now.

 

The SX option was only available on the Cutlass Supreme and only in 1970-71 model years. As with the W-30 package, there was no was to verify this on a particular car without the build sheet.

I will say that I saw one car that was claimed to be a 1970 SX. The car was sold by a reputable Olds "expert" and had the correct, though not numbers matching, engine and trans. While working on the car for a friend, I noticed that the frame showed evidence of the trans crossmember having been previously installed in the TH350 location. Yes, it's possible that the original TH400 had been temporarily replaced with a TH350 - I've even done this myself - but it also brings into question whether or not the car was an original SX.

 

The SX moniker wasn't an abbreviation for anything in particular, just the combo of letters chosen for the Y-79 option. There's lots of info at www.sx455.com.

You definitely need original paperwork to prove that an SX is real unless it's a 1970 W-32 with an OG trans that matches the VIN on the car. The W-32 SX was the only Supreme hardtop to use this trans, which was also shared with base 442 hardtops and ragtops that year.

Most VIN number matching 455-powered Supremes from 1970 and 1971 were likely SXes, although I have run across a few documented 455 powered '70 Supremes that were not SXes as I've scoured the web over the past 10 years or so collecting SX-specific data, pics, etc.

Terry

 

I seem to recall something about the fender seams being double folded or something. Different from the standard Cutlass. Great car. Hang on to it. Chumley

 

Iowa442, can I please get some pics and info on your car? I'm one of the co-founders of the www.SX455.com website and I'd like to be able to add your car if you don't mind. I also agree that if you bought it more than 10 years ago, it's very unlikely that it's not a real SX. Nobody was cloning these cars.
Terry

 

Rocketradier has boughtup an excellont point. A classice car dealship, In Freeport, Maine, Classic Convertibles are a red(white top and white guts) 1970 442 clone ragtop. Has a W-25 hood, wing a/c, but not hook-up, does not have teh 4 spoke 442 wheel, non match 445 motor, no E haeds , in correct air cleaner(espeially for that W-25 hood.
The long of the short of the story, is that it is an orignal 1970 SX Cutlass conv(many folks told Roger to keep it as a SX car - but NOOOOOOO, he made it an 442 clone).
Any ho he had a price this summer of $35,000, then 27,000 -m he might be $19,000.
He think just becasue it has a 442 name on it, he will get more money for it. Fat chance.

 

Just what the world needs - another red 442 clone. What a crappy job - side stripes are all wrong (at least they didn't do the wide W-30 stripes), the decklid stripes are all wrong, they left the keyhole emblem that no 442 had, and the door panels are 71 or 72 repros with woodgrain that doesn't match the dash/console burlwood. No convertibles had the rear spoiler from the factory so that will be expensive to put back to stock. At least it wasn't a numbers matching SX, but it's annoying to me nonetheless. Not all 442s had the sport steering wheel, by the way. It was an option on 442s and Cutlasses but not standard 442 equipment.

 

About 25 yeras ago, a guy that I knew who worked at a body shop bought a '70 SX convertible that someone had brought in that had met a tree *** backwards. He repaired the frame and body, changed the paint from silver to dark blue and replaced the SX tags with 442 tags. I never understood why he had to have a 442 instead of being happy with an SX.

 

Besides the notched rear bumper, trumpet exhausts and SX emblems... other clues that indicate a real SX are a front anti-sway bar, and the additional fender bracing that came on the big block cars.

 

1) This thread is over a year old

2) Every Cutlass ever make came with a front sway bar

3) Everything noted can be bolted on to a non-SX.

 

I remember when I saw TWO SXs heading towards each other in Rockville, MD in the 1980s. Memory plays funny tricks, but I think both were ragtops, one of each year. I saw them about a minute apart. What were the chances?

On the other hand, while not quite DC, DC is/was a good place to find old cars, especially in comparison to other cities in the northeast.

 

As an owner of a 1970 Cutlass SX convertible (2 barrel car) Is it the Y-79 option on the build sheet or is it the L-33 (455 engine)that designates the specific SX option code? I see it here as the last thing printed on the bottom of the last row on the right side of the build sheet. I know that this car was a continuation of the "turnpike cruiser" that was 1st built in 1967. Mine has the standard gears which are 12 bolt posi 2.56 to 1 ratio. I was told this was the standard gear unless optioned with something else. Should be good for 3000 rpm at 70 mph which makes this car great on the highway. Luckily for me I have the original window sticker, protecto plate and build sheet (car was over $5400.00 brand new from Black Cadillac-Olds in Greensboro NC) And the prvious owner lamenated both the build sheet and window sticker which was pretty smart to stop it from deteriorating. Mine was built in Linden, NJ Thanx for the info guys. Oldsdroptop

 

The Y-79 should should be the SX option. The other L-33 code sounds like it could be an engine code, but I'm not positive. Also read that early 70 SX's had the 2bbl set up but they changed to the 4bbl midway through '70. I'm wondering if a 455 was available in 70 or 71 as a non SX or 442 model?

 

The L-33 is the 455 2 barrel. I've been gathering Supreme and SX info for years and have come across a handful of '70 Supremes that were factory L-33 cars but not Y-79 SXes. I have not seen any non-SX L-31 Supremes yet, and the W-32 was only available in a Supreme if it was an SX in 1970. I will be creating a separate section for these oddities on the SX455 registry site at some point.

And yes, the L-33 455 was available in the fastback Cutlass/Cutlass S as well as wagons and big cars.

Terry

 

This bulletin should help - probably was courtesy of Terry.

 

gotta keep this thread alive

it will make your day when while dropping the tank to replace the sending unit you find this piece of paper. note last item in right column

 

I bumped this for the SX fans in the crowd. I loved my SX. 2.56 posi was so cool. I loved it.

 

Thanks

 

So if mine has the dual trumpet exhausts and an automatic transmission, the stripes on the front are faded and spot on, and has SX badging with the original 455 and the notched bumper, and automatic transmission, i have the real deal? My family friend i got mine from said the original owner is getting me a replacement title, and all the VIN numbers add up. It is a gift to replace my Delta 88. Ive been wanting a car with comfort and power that i can drive on special occasions. This is it.

 

How does the VIN add up?

 

An authentic SX?

https://www.ronstoybox.com/vdp/18085...ndorf-IA-52722

VIN 342670E115685

 

Yes - the lower right side of the build sheet shows the Y79 option. The stripes and rear spoiler are not factory correct however, and the OAI hood been added as well.

Terry

 

The stripe and wing didn’t look correct at all. Described as a 6-speed? With all of those mods, do you trust the build sheet?
Thanks Terry.

 

In a make believe world would it be ok to shoot the person that put these stripes on??? 😂🤮

Oh and the wonderful towel rack. That and the body color wheels. So much I love for 60k.

 

Whutchoo mean? That's the way I'da ordered it!😠

Heard it too many times from people who weren't around when the cars were new, and who have no clue about certain options not available in combination with other options, or not available at all.

Or worse didn't understand the market forces at work back then. See: fully optioned 1957 BelAir. Doubtful Chevrolet ever built one loaded up the way a lot of the resto crowd does. Suuure they'd have ordered a fully optioned Chevy, making $1.00 an hour. If they made enough $$$ to afford an optioned out Chevy, they probably moved up to a higher line GM car. Like an Oldsmobile!😎

 

The fender badging locations are “creative.”
And the “added” OAI hood wasn’t adjusted to fit.

 

Would be a beautiful car done right. Those side stripes. Those deck lid stripes. Towel rack that was never available on a ragtop other than a pace car. Huge issues to change to make right. Too bad.