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Saw this on Facebook and noticed the reply. Is it true that no 455 4 spd Supremes were available in '70 or '71? Is that because the SX was available in '70 and '71, but then they dropped them for '72 and thus the 4 spd was available with a 455 Supreme in '72?
Which is to say it could still have matching VIN derivative numbers located on the transmission and the engine block plates (both could have been donors from the same car with matching VIN derivatives); however, those VIN derivative numbers will not match the VIN number located on the windshield dash plaque of the advertised vehicle.
I guess the point of my question is why weren't 4 spd 455s available in the Supreme for '70-'71, but they were for '72? Were 4 spd 455s only available in the SX for '70-'71, but not the Supreme?
From the 1972 Power Teams page. Keep in mind that for the 1972 model year, the only way to get a 442 convertible with a 455 and four speed was to order a Cutlass Supreme convertible with the W29 option and the appropriate drivetrain. Had the 455/4spd not been available in the Supreme that year, it would not have been possible to get a big block manual trans 442 convertible. Lesser Supremes benefited from this fluke as a result.
I guess the point of my question is why weren't 4 spd 455s available in the Supreme for '70-'71, but they were for '72? Were 4 spd 455s only available in the SX for '70-'71, but not the Supreme?
The SX came with a T400 only, no manuals. Only way to get a manual trans in a Supreme for 70-71 was to get the 350 motor. Cant say why GM did it this way, but would bet that Olds wanted people to buy the 442 if they wanted a 455 4Speed.
The Supreme was supposed to be the Luxury Gentleman's cruiser
The SX came with a T400 only, no manuals. Only way to get a manual trans in a Supreme for 70-71 was to get the 350 motor. Cant say why GM did it this way, but would bet that Olds wanted people to buy the 442 if they wanted a 455 4Speed.
The Supreme was supposed to be the Luxury Gentleman's cruiser
But you could get a 455 4 spd Supreme in '72...interesting. Maybe it had to do with the detuning for '72?
My Dad married a woman that was best friends with someone that had 71 SX ragtop. I wonder where that car went. It was Aspen green white top and interior. I owned a 70 SX. Absolutely one of my favorite cars. 2.56 posi and a 455? Loved that car.
Last edited by no1oldsfan; Jun 24, 2023 at 11:42 PM.
Emissions control was tightening and carmakers were beginning to have to certify emissions in each engine and transmission combination they offered (this contributed to that corporate engine nonsense in the later 1970s, but that's another story).
Insurance companies were running performance cars thru the wringer and raping their owners with premiums and surcharges. If a car's VIN indicated a performance series, ie 442's 4400, its owner was automatically deemed high risk and punished. This led to Rallye 350s and other cars like them, since their VIN didn't indicate a performance series. Insurers got wise and that (and emissions certification requirements) resulted in the car's engine being identified in its VIN starting 1972.
The NHTSA was flexing its muscles by then too. Can you say ugly bumpers?
It wasn't so much that carmakers didn't want to build appealing and high-performing cars, but with those players in the game and colluding it's not surprising that decently styled and performing automobiles were vanishing by late 70s.
Correct me if I'm wrong, but if a 350 4 speed Supreme was available in '72, what was the VIN designator since the 455 4 speed carried the "V" or "X?" Was it the same for the 350 4 speed?
Correct me if I'm wrong, but if a 350 4 speed Supreme was available in '72, what was the VIN designator since the 455 4 speed carried the "V" or "X?" Was it the same for the 350 4 speed?
The VIN designators for the 350 did not change for the trans. It didn't for the W30 either, which was an "X" for both AT and MT, despite the different cams and tuning.
The VIN designators for the 350 did not change for the trans. It didn't for the W30 either, which was an "X" for both AT and MT, despite the different cams and tuning.
So the 350 4 spd and the 455 4 spd both carried the V and X designator (respective of the W-30 option?)
So the 350 4 spd and the 455 4 spd both carried the V and X designator (respective of the W-30 option?)
Huh? No. Let's try this again. Here are all the engine codes used in the fifth position of the VIN for the 1972 model year:
H = 350 2bbl single exhaust 160 HP any trans RPO L32 (A-body) and L33 (full size)
J = 350 2bbl dual exhaust 170 HP any trans RPO L32+N10 (A-body)
K = 350 4bbl single exhaust 180 HP any trans RPO L34 (A-body) and L35 (full size)
M = 350 4bbl dual exhaust 200 HP any trans RPO L34+N10 (A-body)
T = 455 4bbl single exhaust 225 HP AT only RPO L74 (full size) Note: also available with dual exhaust as L74+N10
U = 455 4bbl dual exhaust 250 HP AT only RPO L75 (A-body) and L78 (Toro)
V = 455 4bbl dual exhaust 270 HP MT only RPO L76 (A-body)
X = 455 4bbl dual exhaust 300 HP any trans RPO L77 (A-body)
Last edited by joe_padavano; Jul 23, 2023 at 06:50 PM.
Huh? No. Let's try this again. Here are all the engine codes used in the fifth position of the VIN for the 1972 model year:
H = 350 2bbl single exhaust 160 HP any trans RPO L32 (A-body) and L33 (full size)
J = 350 2bbl dual exhaust 170 HP any trans RPO L32+N10 (A-body)
K = 350 4bbl single exhaust 180 HP any trans RPO L34 (A-body) and L35 (full size)
M = 350 4bbl dual exhaust 200 HP any trans RPO L34+N10 (A-body)
T = 455 4bbl single exhaust 225 HP AT only RPO L74 (full size) Note: also available with dual exhaust as L74+N10
U = 455 4bbl dual exhaust 250 HP AT only RPO L75 (A-body) and L78 (Toro)
V = 455 4bbl dual exhaust 270 HP MT only RPO L76 (A-body)
X = 455 4bbl dual exhaust 300 HP any trans RPO L77 (A-body)
Thanks Joe...IOW, the only engine that carried the separate designator for the transmission was the 455 whereas the 350 did not, correct?
Huh? No. Let's try this again. Here are all the engine codes used in the fifth position of the VIN for the 1972 model year:
H = 350 2bbl single exhaust 160 HP any trans RPO L32 (A-body) and L33 (full size)
J = 350 2bbl dual exhaust 170 HP any trans RPO L32+N10 (A-body)
K = 350 4bbl single exhaust 180 HP any trans RPO L34 (A-body) and L35 (full size)
M = 350 4bbl dual exhaust 200 HP any trans RPO L34+N10 (A-body)
U = 455 4bbl dual exhaust 250 HP AT only RPO L75 (A-body) and L78 (Toro)
V = 455 4bbl dual exhaust 270 HP MT only RPO L76 (A-body)
X = 455 4bbl dual exhaust 300 HP any trans RPO L77 (A-body)
Quoting 1972 SPECS, W29 was available with "any engine," could you choose any of these engines with the 442 package in 72?
Quoting 1972 SPECS, W29 was available with "any engine," could you choose any of these engines with the 442 package in 72?
Any engine that was available for use in the A-body platform could be used in a W-29 442 equipped car. In 72, the W-29 442 package was an appearance and handling package. So you could have a 350 2bbl all the way up to the W-30 X code 455
To the original question- as mentioned no 4-speed SX's, ever... I always thought that the reason was if you wanted a big block four speed you had to get a 442. I believe they only made about 900 4 speed Supremes in 1970 overall- demand was very low. I have owned two 1970 4-speed Supremes and have one I owned 30 years ago back again (gone 1996-2020).
Factory 4-speed car, added the big block and SX badges (give me a break on that it was 25 years ago-Ha) In retrospect I would have left the 350 4bbl in it and kept the vinyl roof and original color.
Burgundy mist and a 4 speed Supreme?! That'd be a sweet car there, fasteddy. When I was in high school, down the street, there was a lady, probably in her early 30's that had two Supreme's. She daily drove a saddle bronze (I think that's the color name) 72, and the other was a 70, aspen green, pearl interior and white vinyl top 4 speed. It was a beautiful car. She babied the heck out of it. I offered to buy it at least a half dozen times before I started to realize she absolutely loves her Olds and was probably not going to part with it. It was the only 4 speed Supreme that I had ever seen, and to this day, I have yet to see another in person. I kept in touch with her and when I'd see her out and about I'd stop by and chat with her. She ended up moving out of state sometime around 2006 and she took both Supremes with her. If she still lived here, I probably would still be bugging her to sell that 70 to me. SSI wheels, anti-spin rear, dual exhaust, pdb in front, no a/c, buckets, console...such a cool car. I would have liked to own that one.
Interesting,
So what was the code for a 72 4spd G A 2.07" 1.685" 455 ?
I've read only the stick non AC obviously but that's hotter than the auto heads. W45/46 .
Is that true...
Reminds of another it can't be from '69
Quick erase the internet
Last edited by LOUCKES'6487; Nov 19, 2023 at 03:03 PM.
ST W30 cam is hotter than the AT also gets the biggest exhaust valve too with 4spd. 409759cam vs smaller 691cam shared in L77 code and L75.
L75 , L77 same 691 cam.
That implies two L77 , only one W30 with big valves in and out?
W30 759 cam being L77X with 4spd heads GA 2.07/1.685". So HP at 300 can't be accurate for more than one configuration. Which brings up the blueprint hand fitted motors as well.
I just read here..
"Ga 409100 [same number as G head] 80cc 2.000, 2.072" 1.625, 1.685"1972 455's, including W-30. Valves almost universally 2.000 and 1.625", even 442's had small intakes, if auto trans models. Even the Toronados were relegated to small intake valves this year. Only 442's with W-30 or MT had the larger 2.072" intakes. No way to tell valve size without measuring a valve. Strange combinations of exhaust valve sizes and angles, depending on application. Weird combination of valve sizes and seat angles that no other heads matched. This might make finding valves more fun, should you need them. Exhaust valve with a unique 1.685" diameter and 30 degree face. All Ga heads use valve rotators on all valves, therefore have all deep spring seats. Hard exhaust seats."
Last edited by LOUCKES'6487; Nov 19, 2023 at 10:31 PM.