1970 Chevrolet Chevelle SS
A-body · Peak SS production year. The LS6 454 with 450hp is considere... · The peak of GM muscle — LS6 454 is the most powerful factory muscle car ever
Highly Collectible
Production & Overview
Total Production
53,599
Original MSRP
N/A
Assembly Plants
Baltimore, MD · Kansas City, MO · Fremont, CA · Arlington, TX · Van Nuys, CA
Wheelbase
112 inches
Body Styles
Sport Coupe · Convertible
Curb Weight
3,750 lbs
Notable Packages & Production
LS6 454 — LS6
450hp 454 — highest factory muscle car horsepower ever rated
4-7x base SS
4,475
produced
COPO Chevelle — COPO
Central Office Production Order — dealer-ordered special builds
6-10x base
323
produced
Available Engines
L34 396ci — V8
Base SS big block — actually 402ci but badged 396
350 hp
L78 396ci — V8
High-performance 396 — solid lifter
375 hp
LS5 454ci — V8
454 big block — new for 1970
360 hp
LS6 454ci — V8
The king. 450hp factory rated — highest factory horsepower ever in a muscle car. Solid lifter, 11.25:1 compression. Required Muncie 4-speed or TH400.
450 hp
Buyer Checklist
⚠ Clone warning: Non-matching LS6 loses 40-60% of value. LS6 identification requires engine suffix code and date codes on heads and intake.. Always verify with cowl tag, engine stamp, and registry before purchase.
Decode cowl tag — verify SS package, engine option, and paint code
Check engine suffix code — must match VIN for numbers-matching
On LS6 — verify head casting numbers (3964291) and intake manifold
Inspect floor pans and trunk — A-body rust points
Check lower rear quarters and wheel arches for rust
Verify rally wheels are correct size for claimed engine
Inspect frame rails under front subframe
Look under rear seat for build sheet
On convertibles — check frame for rust and structural integrity
Verify Muncie M22 Rock Crusher if claimed with LS6
Known Problem Areas
Floor pan and trunk floor rust
Rear quarter panel rust at lower edge
Frame rail corrosion on northern cars
Clone LS6 — standard 454 (LS5) presented as LS6
Clone SS — base Malibus converted to SS appearance
Subframe corrosion at body mounts
What Drives Value
↑ Increases Value
LS6 454 — matching numbers with documentation
COPO Chevelle
Convertible body style
4-wheel disc brakes (JL8) — very rare
Muncie M22 Rock Crusher 4-speed
Original paint confirmed by cowl tag
↓ Decreases Value
Clone LS6 (LS5 with LS6 cosmetics)
Clone SS
Rust in frame or floor structure
Non-matching engine
Non-original paint
Restoration Overview
Difficulty
Medium
Parts Availability
Excellent — strong A-body reproduction market
Driver Quality Cost
$18,000 – $40,000
Show Quality Cost
$55,000 – $130,000
Key Suppliers
Classic Industries · Ground Up SS · Year One
Pop Culture & Legacy
Consistently ranked in top 5 most desirable American muscle cars
The LS6 is cited in virtually every muscle car power ranking as the pinnacle
Used extensively in automotive journalism to define the muscle car era
Hot Wheels and die-cast favorite
Other Chevrolet Chevelle SS Years