Aluminum vs, Cast Iron Block

[82ACAUTOCRAFT]

The Rover V8 is actually quite unreliable and it is similar to the FE in a smaller package. It's why I brought the subject in this thread. The early Buick blocks did not suffer from early failures as the Rover do because of the block casting process and bore size. GM dropped the aluminum version because of cost and started producing the engine in cast iron in Buick's and Oldsmobile's in the mid 60's. The Rover block is sand cast and the bores have grown bigger over the years making the walls too thin. The Rover engine suffered from main bearing failure and Sleeve failure. (Mainly in 4.0 and 4.6 liters Range Rovers where this engine works very hard and engine temperature has to be kept high for emission requirements). In the 90's, Rover introduced a cross bolted design much like the FE 427 and solved the main bearing problem. However, the sleeve failure remained and is due to the walls behind the sleeve being too thin and cracking and the sleeve moving down and letting coolant in the cylinder. When this happens, mechanics not familiar with the Rover V8 think the head gasket has blown when in fact it is much more serious and the block is in fact dead. Some aftermarket British companies now cast their own block with flanged sleeves to prevent this from happening again. One even makes a big bore Siamese design which works quite well. Having owned a couple of Range Rovers and a Morgan Plus Eight, I am all too familiar with this engine. Ironically, head gasket failures on Rover V8 are rare.