Another feature that was incorporated during the design is the new 35cc combustion chamber shape. Factory Rover cylinder heads feature a D shaped combustion chamber. The new TA Rover head features a Heart shaped combustion chamber as found on all high performance cylinder heads. This results in better combustion and a decrease in the possibility of detonation, due to the more compact chamber, which increases performance.
The chamber and deck thickness are also increased to at least 5/8" or thicker. This makes the heads stronger so they can handle more power without flexing and cracking, a potential problem on high horsepower or forced induction engines.
The valve cover rail has also been raised to make way for additional material which gives you the ability to raise the intake ports to make it a tall port head. A raised runner provides a more direct flow to the valve resulting in additional CFM over the standard port head, approximately 10-15 CFM on average.
Accessory bolt hole patterns for both the 14 and 10 bolt Rover heads have also been incorporated so that the heads fit the early 14 bolt and the later 10 bolt Rover blocks. While this cylinder head was designed for the Rover V8, it will also bolt on to Buick 300/340 blocks with minor modifications.
The stock Rover exhaust should bolt right up, but as the exhaust ports have been raised 3/4" there may be some fitment issues on some cars. In addition to the Rover valve cover bolt pattern, the 350 Buick valve cover bolt pattern has been incorporated on these heads allowing the use of 350 Buick valve covers for better clearance with roller rockers or for those looking to use these heads on a Buick 300/340.
These heads will require new rocker arms, the stock rocker arm setup is not compatible with these heads. There are two options shaft mounted roller rockers or Chevy style pedestal mount roller rockers.