What kind of engine does a Pontiac 421 HO have?
First offered as an option in 1963, the 421 HO came in a 4-barrel engine of 320 hp (239 kW) and one Tri-Power H-O version with a hotter cam and efficient iron exhaust manifolds and rated at 370 hp (276 kW). Pontiac offered this to the public as a streetable version of the 421 SD.
What was the horsepower of a 1964 Pontiac GTO?
These same heads were also used on the 1964 GTO 389 tri-power engines. By 1965 and 1966 the same combinations would be rated at 338 hp (252 kW) for the 4bbl and the two Tri-Power versions would be rated at 356 hp (265 kW) and the H-O version at 376 hp (280 kW).
How big is the connecting rod on a Pontiac V8?
Effectively, Pontiac’s V8s were all small blocks, sharing the same connecting rod length 6.625 in (168.3 mm) (except for the later short deck 301 and 265 produced in the late ’70s and early ’80s before Pontiac adopted universal GM engines).
What kind of engine did Pontiac have in 1955?
The 1955-up Pontiac V8 that finally reached the public was an overhead valve engine with cast iron cylinder heads and block and wedge-shaped combustion chambers. An innovative design feature was mounting the rocker arms on ball pivots on studs set into the cylinder head, rather than using a separate rocker shaft.
First offered as an option in 1963, the 421 HO came in a 4-barrel engine of 320 hp (239 kW) and one Tri-Power H-O version with a hotter cam and efficient iron exhaust manifolds and rated at 370 hp (276 kW). Pontiac offered this to the public as a streetable version of the 421 SD.
What kind of engine did the Pontiac 428 have?
The 400-cid Pontiac V8 that bowed in 1967 Pontiacs was a bored-out version of the 389 and a new 428 was a bored-out 421. The extra cubes were added to mask the fact that Tri-Power options were no longer offered.
What kind of engine does a Pontiac 389 have?
It was a de-stroked version of the 389 with a four-barrel carburetor and 260 hp. Pontiac continued with Tri-Power options for both the 389 and 421. Two 421 H.O. V8s produced 353 and 370 hp, but the hottest options of all were the 390-, 405- and 410-hp versions of the 421 Super-Duty V8.
These same heads were also used on the 1964 GTO 389 tri-power engines. By 1965 and 1966 the same combinations would be rated at 338 hp (252 kW) for the 4bbl and the two Tri-Power versions would be rated at 356 hp (265 kW) and the H-O version at 376 hp (280 kW).