When the production requirement was dropped, Pontiac halted the planned 250-unit run to cut warranty costs. Although it was a spectacular performer, the high-strung engine was too fragile for street use. The motor used a shaved 400 block fitted with a radical tunnel port intake to create a short-stroke, 303-cubic-inch engine that redlined at 8,000 RPM. The pinnacle of the Trans Am lineup was to be the new Ram Air V, developed to meet the Trans American Racing Series’ 5-liter, 305-cubic-inch engine homologation requirements. Unlike most contemporary performance engines, it managed to produce power without sacrificing reliability or low-end torque, making it perfect for street use while still being competitive on the track. Introduced in the middle of the 1968 model year, the engine was available in the GTO, Judge, Firebird and Trans Am through 1970. When Hot Rod magazine tested a Ram Air IV-equipped Trans Am, it did the quarter mile in 14.1 seconds, breaking 100 miles per hour in the process. Flow was further improved with an aluminum intake manifold, which also shaved 15 pounds off the completed block, giving the engine power throughout the rev range. 520 inch lift with 308 degree by 320 degree duration, a huge jump from the III’s 288 degree by 302 degree duration. Round port heads improved flow while the engine’s unique cam profile provided. The factory rated the Ram Air IV at 345 horsepower, just 10 more hp than the Ram Air III, but a look at the spec sheet tells a different story. Engine on the 1969 Pontiac Firebird Ram Air IV However, circumstances related to Pontiac’s involvement in the series lead to the most powerful version, the Ram Air IV, being one of the rarest muscle cars ever produced. In 1969, Pontiac introduced the Trans Am, a race-bred version of the Firebird that used the “race on Sunday, sell on Monday” approach by competing in the Trans American Racing Series. These heads will also require special intake manifolds.Ģ.11 Intake Valve, Screwed Stud, Auto TransĢ.1969 Pontiac Firebird Ram Air IV – Power and Performance The Ram Air IV also has a taller intake port and the Ram Air V has Round Intake ports. Make sure to use the correct intake manifold. From 1972 up Pontiac also changed the head’s exhaust crossover. From 1967 to 1979 Pontiac engines used the same pushrods, Rocker arm, and valve covers. However, they are harder to find and like the 1967 heads, they have a closed combustion chamber.Įxcluding the Ram Air IV and Ram Air V heads. The 19 Super Duty engines would work well also. Then the best option would be to choose a high output Pontiac heads produced from 1967 on. There are aftermarket heads available but, If you don’t want to use aftermarket heads. Looking for a performance head for your Pontiac? These heads flow better producing more power than the heads produced pre-1967. The high output heads produced by Pontiac after 1967 used bigger intake and exhaust valves and a 14-degree valve angle. Pontiac heads produced PRE 1968 used a closed combustion chamber design while heads produced from 1968 on used an open chamber. Except for some special heads the bolt pattern, the bore spacing, and deck heights are the same. All Pontiac V8 cylinder heads from 1955 to 1976 are essentially interchangeable. Pontiac used different valves and combustion chamber size for their V8s to change compression ratios, fuel economy, and horsepower output. Over the years Pontiac v8 Cylinder heads came in many specifications. Ram Air III Pontiac Heads Pontiac V8 Cylinder Heads.
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