Reference Details
- Common issue
- The 754-car all-Pontiac 421 HO figure is misreported as Grand Prix production, or a Tri-Power conversion is called an original HO. · 1965 Pontiac Grand Prix
- Confidence
- documented · 1965 Pontiac Grand Prix
- Correct value
- A 421 HO claim requires the individual Pontiac billing record and matching high-output equipment · 1965 Pontiac Grand Prix
- Where to check
- PHS invoice, engine code and date, heads, cam, induction, exhaust and cooling equipment · 1965 Pontiac Grand Prix
- Common issue
- A standard 421 or added Tri-Power is represented as an original 376-hp 421 HO. · 1966 Pontiac Grand Prix
- Confidence
- documented · 1966 Pontiac Grand Prix
- Correct value
- A 421 HO claim requires the car's billing history and matching high-output components · 1966 Pontiac Grand Prix
- Where to check
- PHS invoice, engine code and date, cam, induction, exhaust, cooling and ignition equipment · 1966 Pontiac Grand Prix