The Pontiac 428 cubic inch engine was used only from 1967-69. It was one of the largest engines Pontiac produced, but it was used more to power big cars such as the Bonneville, and not as much for performance cars such as the Firebird.

What is a 428 Pontiac engine?

The 428 was Pontiacs top engine for 3 short years- 1967-9. The bore is the same as the 400 at 4.12". The stroke is 4", the main journals are 3.25". The 428 has remained one of the favorite Pontiac engines for racers and hot rodders and, are always one of the most sought after for a build up.

How do I know if I have a 428 Pontiac?

On 1968–69 428 blocks you will find “428” stamped between the freeze plugs. On blocks produced in 1970 and after, you will find 350, 400, or 455 stamped towards the left side of the front of the block.

Did GM make a 428?

Intended for full-size cars, Pontiac's 428 has plenty of muscle car history, even if it took some aftermarket wrenching to make it so. GM had an internal policy that limited mid-size cars to engines no larger than 330 cubic inches.

What was the most powerful Pontiac engine?

The most powerful version of Pontiac's 400 to ever reach production was the Ram Air IV. With its improved cylinder heads and their round exhaust ports, they're easy to spot.

1969 Pontiac GTO 428 Performance Engine By Proformance Unlimited

24 related questions found

How much horsepower does a Pontiac 428 have?

The 428 was rated with 260 horsepower at 4,600 rpm, and that could be boosted to 270 with some factory modifications. The engine had 472 foot-pounds of torque, or pulling power, at 3,200 rpm.

Did Pontiac make a Hemi engine?

This was a project started by Pontiac with the end goal of building a Pontiac 427 Hemi. Surprisingly, Mopar actually agreed and sent over several of the engineers that designed both the 392 and 426 Hemi. ... The goal of making a Pontiac Hemi succeeded but was never produced.

Did Pontiac make a 400 small block?

The basic 400 continued through the 1978 model year, and the 428 grew into the 455 for 1970 when a 0.21-inch increase in stroke was added to its crankshaft. The 455 went away after 1976, and Pontiac went to work developing an entirely new small-displacement V8 whose total design was aimed at maximizing fuel economy.

Did Pontiac make a 350 big block?

But it's been over 20 years since GM produced traditional Pontiac V-8s, and the supply of desirable big-inch blocks is drying up. Yet the orphan 350--produced from 1968-1979--is still fairly common, precisely because no one wants them. Pontiac's 350 shares the same external dimensions with its larger brothers.

Are Pontiac 670 heads good?

670 heads are one of the most effective heads for making power--they're excellent heads. That said, they are the last of the closed chamber, early style heads with the big valves. They were designed for 100 octane fuel, cheaply and readily available in the '60's.

Are 62 Pontiac heads any good?

These heads actually make very good platforms for a good performing 400, since the compression is moderate enough for modern pump gas. The heads can be ported, upgraded with some nice stainless valves, and given a good 3- or 4-angle valve job to produce pretty respectable flow and performance.

Are 16 Pontiac heads any good?

The #16 head is a good head to use use to build power with if it is the round port or the large valve screw in studs. Otherwise a boat anchor would be just as good. As far as the 670 heads they are a closed chamber head from 67. I've always like them.

What is the biggest Pontiac engine?

The 455-cu.in. V-8 debuted in 1970 and was the largest displacement Pontiac engine ever built for the street.

Did Pontiac make a 426 engine?

Pontiac increased the 421's bore to 4.12 inches, which produced 426.5 ci when combined with the 4-inch-stroke crank. To maintain its own identity in a market filled with the 426 Hemi and 427 Chevy, Pontiac's was billed as a “428.”

What is a 427 engine?

The 427 engine is a variation of the Chevrolet Mark IV big-block engine family and can appear outwardly similar to other engines in the Mark IV family such as the 396 and 402. The surest way to identify a 427 engine is to decode the engine casting number located on the engine block.

What years did Pontiac make the 421 engine?

The 421 SD became factory installed in 1962 and in 1963 a street version became available from the factory with a dual four-barrel or three two-barrel Tri-Power carburetion. Modified versions of this engine were extensively used in NASCAR stock car racing and drag racing competition.

Did Pontiac use Oldsmobile engines?

The Olds 403 was used by Buick and Pontiac in addition to Oldsmobile until its discontinuation after 1979. Output was 185 hp (138 kW) and 320 lb⋅ft (430 N⋅m). Uniquely in the 1977 Toronado, the 403 engine was fitted with a crank triggered ignition system.

Which engines are considered Pontiac big blocks?

The only "big blocks" in the GM family are Chevrolet's 396/402/427/454 family which are easily identified via their massive rocker arm covers that no Buick, Olds or Pontiac 455 exhibit.

Who made the 421 engine?

Responding to Ford, Chevy, and Chrysler each topping the 400-cubic-inch mark with their own competition engines, Pontiac introduced the 421 Super Duty for 1962, though a few engines went to select drag racers late in the 1961 season.

What engines were available in a 1967 GTO?

Of the 81,722 GTOs built for '67, 13,827 were equipped with the HO engine. Underhood, a 400-cid V-8 replaced the hallowed 389. For another $263, the 1967 Pontiac GTO's HO mill could be fitted with Ram Air.

Is a 1970 Pontiac 400 a big block?

The 1970 500 cubic-inch, 8.2-litre Cadillac V8 was a big engine (indeed a rather massive engine); but alas, was not a big block. ... A Chevrolet Camaro 396 had a big block, but a Pontiac Firebird 400 did not. Buick and Oldsmobile 455s were big blocks, but a Pontiac 455 was not.

Did Pontiac make a 409?

Semco's 409CI Pontiac Was Built For The Jegs Engine Masters Challenge, And Cranked Out 561 Hp On Pump Gas. The Engine Masters Challenge was designed to bring the best efforts of veteran engine builders to the forefront with street-based limitations.

How much horsepower does a 400 Pontiac have?

The 400 pushed this number up to 360 horsepower, with the same Quadrajet single four-barrel.

What is a Pontiac 6.6 engine?

Pontiac Firebird II Trans Am 400cu 6.6L Specs

With a curb weight of 3666 lbs (1663 kgs), the Firebird II Trans Am 400cu 6.6L has a naturally-aspirated V 8 cylinder engine, Petrol motor. This engine produces a maximum power of 350 PS (345 bhp - 257 kW) at 5000 rpm and a maximum torque of 583.0 Nm (429 lb.