1970 Pontiac GTO 455 HO

Muscle car powered by Pontiac 455 HO V8.

1970 Pontiac GTO 6.6 front view photographed by Vauxford; exact-year GTO exterior context for the 455 HO page.

Engine 455 cu in Pontiac L75/HO V8

Rating 360 hp and 500 lb-ft in GTO references

Known production 4,146 GTO 455 HO cars reported in GTO production tables

Character Long-stroke torque alternative to the higher-revving Ram Air 400 cars

Authentication focus PHS paperwork, engine stamp/casting/date codes, transmission, axle, and Ram Air inlet evidence

Story

1970 Pontiac GTO 455 HO

The 1970 Pontiac GTO 455 HO is the torque-heavy GTO that arrived after GM relaxed the intermediate-car displacement ceiling. It was not a Judge-only story and it was not the later round-port 1971-1972 455 HO. For 1970, the GTO 455 HO was a D-port Pontiac 455 with the kind of low-speed pull that made the car easier to launch and live with than the peaky Ram Air 400 combinations.

Pontiac-era and enthusiast production references separate the 455 HO from the Ram Air III and Ram Air IV branches. The New Hampshire GTO Club production table reports 40,149 total 1970 GTOs and 4,146 with the 455 HO. Over-Drive's 1970 Pontiac mid-size fact sheet summarizes the 455 HO as a new long-stroke option rated at 360 horsepower and 500 lb-ft of torque, and the period road-test material explains why the 455 car felt different: it traded top-end theater for easier torque.

The important caveat is documentation. A 1970 GTO 455 HO claim should not rest on a fender badge, a restoration photo, or a sales listing alone. PHS paperwork, engine unit and block stamping evidence, casting and date-code alignment, transmission, axle, Ram Air inlet evidence when present, and body/trim records are the difference between a real 455 HO record and a nice GTO with a swapped engine.

This page treats paint, interior, brakes, suspension, axle, and appearance details as factory-availability records unless a specific car's paperwork proves more. The gallery uses exact-year 1970 GTO media and clearly labeled Judge or road-test context only where it helps explain the shared GTO body, Ram Air, Rally II, and trim story without turning the photo into proof of a particular 455 HO car.

**1970 Pontiac GTO 6.6 rear view photographed by Vauxford; used for rear trim and GTO identification context.**Vauxford via Wikimedia Commons · CC BY-SA 4.0

Price history

Values

Nominal dollars from original price sheets, auction archives, and approved value references.

Original Price

A verified original price is not yet available for this car.

Market Observations

Price guide value $37,500

Jul 1, 2026 · Hagerty Price Guide · Current guide point
1970 Pontiac GTO two-door hardtop with the 455-cid/360-hp four-barrel engine in #3 Good condition, before transmission or air-conditioning adjustments. · unknown · good July 2026 exact-configuration guide observation. Hagerty displays separate adjustments for four-speed, factory air conditioning, and automatic transmission, so this unadjusted row is not a transaction or a universal value for every 455 HO GTO.
1970 Pontiac GTO hardtop 455/360-hp value
Auction sale $61,000

Jul 17, 2025 · Bring a Trailer
PHS-documented 455 HO four-speed convertible 242670P163636 with a WA-code engine plus aftermarket induction, exhaust, gauges, spoiler, and Judge-style stripes. · modified · good Bring a Trailer records the completed sale, exact VIN, date, amount, 455 HO/four-speed identity, PHS documentation, refurbishment, and modifications. Modified prevents the result from being treated as a stock-presentation benchmark.
1970 Pontiac GTO 455 HO 4-Speed, lot 200789
Auction sale $68,500

Apr 10, 2024 · Bring a Trailer
PHS- and build-sheet-documented L75 455 HO automatic hardtop 242370Z126243 after refurbishment, with a YC-code engine and Y96 Firm Ride suspension. · restored · excellent Bring a Trailer records the no-reserve completed sale, exact VIN, date, amount, L75/automatic configuration, PHS and build-sheet documentation, refurbishment, and engine-code claim. Excellent reflects the disclosed presentation, not an independent inspection.
1970 Pontiac GTO Hardtop 455, lot 142716
Auction sale $75,500

May 25, 2022 · Bring a Trailer
PHS-documented 455 HO automatic convertible 242670B118793 with an overhauled matching-stamp engine, prior bodywork, and visible finish and top flaws. · restored · good Bring a Trailer records the completed sale, exact VIN, date, amount, 455/automatic configuration, PHS and build-sheet documentation, engine-stamping claim, refurbishment history, and disclosed flaws. Good is conservative because prior bodywork, paint flaws, and a torn top were disclosed.
1970 Pontiac GTO Convertible 455, lot 74348
Auction sale $92,000

Aug 14, 2021 · Bring a Trailer
PHS-documented 455 HO automatic convertible 242670B115098 after a body-off refurbishment, with receipts and refurbishment photos. · restored · excellent Bring a Trailer records the completed sale, exact VIN, date, amount, 455/automatic configuration, PHS documentation, body-off refurbishment, and true-mileage-unknown disclosure. Excellent reflects the disclosed presentation, not an independent inspection.
1970 Pontiac GTO Convertible 455, lot 53134
Auction sale $98,500

Oct 9, 2020 · Bring a Trailer
Factory 455 HO four-speed convertible 242670P124739 after a multi-year refurbishment, with a factory build sheet and matching-engine claim. · restored · excellent Bring a Trailer records the completed sale, exact VIN, date, amount, factory 455/four-speed path, refurbishment, engine-stamping claim, build sheet, and condition details. Excellent reflects the disclosed presentation, not an independent inspection.
1970 Pontiac GTO Convertible 455 4-Speed, lot 37599

Values move with paperwork, originality, options, condition, venue, and body style. High bids and guide values are labeled separately from completed sales.

Reference records

Options, Colors & Components

Source-backed details for trim, chassis, production, and authenticity.

Transmission

Factory transmission 4-speed manual context
Factory transmission Turbo Hydra-Matic automatic context; individual cars require PHS/build-sheet verification, and period road tests used both manual and automatic examples

Options

L75 455 HO V8 optional · performance · The 455 HO was the big-cube GTO option for 1970 and is recorded separately from Ram Air III/IV 400 engines.
T42 Ram Air hood inlet optional · performance · Functional Ram Air inlet context appears in period discussion; horsepower rating did not become a separate 455 Ram Air engine record.
G80/G92 context Safe-T-Track / performance axle context optional · chassis · Exact axle ratio and code should be verified against PHS paperwork and axle stamping for a specific car.
Rally II Pontiac Rally II wheels optional · appearance · Rally II wheel context is common in period and media examples but remains car-specific for judging.
VOE Vacuum Operated Exhaust optional · performance · Short-lived 1970 GTO option; page records it as period context, not as standard 455 HO equipment.

Paint

**Cropped front-end detail from approved Vauxford 1970 GTO Commons media.**Vauxford via Wikimedia Commons · CC BY-SA 4.0

10 Polar White factory · solid
14 Palladium Silver factory · metallic
19 Starlight Black factory · solid
25 Bermuda Blue factory · metallic
26 Lucerne Blue factory · metallic
28 Atoll Blue factory · metallic
34 Mint Turquoise factory · metallic
45 Palomino Copper factory · metallic
47 Verdoro Green factory · metallic
48 Pepper Green factory · metallic
58 Granada Gold factory · metallic
75 Cardinal Red factory · solid

Production

**1970 Pontiac GTO photographed by dave_7; used as front-end and body context.**dave_7 via Wikimedia Commons · CC BY 2.0

1970 Pontiac GTO total production total · 40,149 · reported
1970 Pontiac GTO 455 HO by engine · 4,146 · reported
1970 Pontiac GTO convertible total by body · 3,615 · reported
1970 Pontiac GTO VOE option context by option · 233 · reported

Authenticity

**1970 Pontiac GTO photographed by Greg Gjerdingen; exact-year GTO show-field context.**Greg Gjerdingen via Wikimedia Commons · CC BY-SA 2.0

PHS documentation PHS/build documentation should show 455 HO/L75-related engine option and matching drivetrain/options for the claimed car. · PHS invoice, build sheet where available, window sticker or document file. · fraud detection
Engine identity 1970 455 HO is a D-port Pontiac 455 HO/L75 context, not the 1971-1972 round-port 455 HO or the later SD-455. · Engine block code, casting number, date code, cylinder-head casting, and PHS paperwork. · numbers matching
Transmission and axle alignment Transmission and axle records should align with PHS paperwork and physical stamp/date evidence. · Transmission case stamping, axle tube stamp/tag, PHS paperwork, and build sheet where available. · date correctness
Ram Air and Judge separation Ram Air inlet and Judge trim are option/package evidence, not proof that every 455 HO GTO had those parts. · PHS option list, hood hardware, cable/knob evidence, decals/stripe/spoiler evidence, and body trim inspection. · trim correctness

Still Researching

interior Interior records are supported at option/layout level, but exact upholstery codes, trim combinations, and console/gauge combinations are not normalized for every 455 HO body/transmission path.
authenticity markers The page records the major documentation risks, but exact engine block codes, head/carb/distributor numbers, transmission tags, axle codes, and date-code rules need a Pontiac parts/service-manual pass.

Codes & names