1970 Oldsmobile Cutlass Supreme
A-body · Redesigned body. New front styling. 350 and 455 available. S... · Style and substance — Oldsmobile's best-selling classic
Highly Collectible
Production & Overview
Total Production
168,907
Original MSRP
N/A
Assembly Plants
Lansing, MI · Fremont, CA · Arlington, TX
Wheelbase
112 inches
Body Styles
2-Door Hardtop · Convertible · 4-Door Hardtop
Curb Weight
3,650 lbs
Notable Packages & Production
SX Package — SX
2-3x base
uncommon
Available Engines
L34 350ci — V8
Base V8
250 hp
L75 455ci — V8
455 big block — SX option
365 hp
Buyer Checklist
⚠ Clone warning: 455 SX non-matching loses 40%. Always verify with cowl tag, engine stamp, and registry before purchase.
Decode cowl tag for SX and 455 options
Check engine suffix for 455 designation
Inspect A-body floor pans and lower quarters for rust
Verify correct Rally wheels on SX
Check for build sheet under seat
Verify correct 455 exhaust
Inspect convertible top mechanism if applicable
Check all Supreme-specific chrome trim
Road test: 455 has massive low-end torque
Verify rear axle ratio
Known Problem Areas
Floor pan rust
Lower quarter rust
455 engine oil leaks
Clone SX cars
Convertible top mechanism wear
What Drives Value
↑ Increases Value
SX 455 convertible — premium combination
SX 455 hardtop with 4-speed
Numbers-matching 455 with cowl tag
Rare color combination
↓ Decreases Value
Non-matching 455
Clone SX
Heavy rust
Missing specific trim
Restoration Overview
Difficulty
Medium
Parts Availability
Good
Driver Quality Cost
$15,000 – $30,000
Show Quality Cost
$35,000 – $70,000
Key Suppliers
Olds Central · Ground Up SS · OER
Pop Culture & Legacy
One of the best-selling American cars of 1970
The Cutlass Supreme defined Oldsmobile's blend of performance and luxury
Strong following at Oldsmobile Club of America events
Other Oldsmobile Cutlass Supreme Years