The Rover-Landers of BC

Hello all, in an attempt to squeeze more "power" out of my 2.25L in my 1966 LR series 2a I was thinking of installing an 8.1 cylinder head. However I should first make sure I don't have one already. Can anyone tell which one I have from the picture?//uploads.tapatalk-cdn.com/2016073 ... c999e4.jpg


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Sometimes they are stamped on top. It is a newer head as the older ones had a deeper thermostat housing. Why not just skim the head you have?

Mike

I was think of shaving it down, just want to make sure I don't already have an 8.1 already.


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Hello from Brisbane.

Probably a bit late for a response, but in case not the answer to your original question is as follows:

DETERMINING COMPRESSION RATIO OF A 2.25L PETROL LAND ROVER ENGINE:

There are multiple head castings used on the 2.25L engine over the years. The two standard compression ratios used by Rover were 7:1 and 8:1.

The easiest way to determine a head's compression ratio is to look at the top surface between the valve cover and the carburettor. You will see a head bolt located there. On some heads there is a flat rectangular boss under the head bolt that extends towards the carburettor to the edge of the head.

If the head does not have this boss it is an early 7:1 compression head. If the head has the boss it is a later casting that came in both 7:1 and 8:1 versions, depending upon the country that the car was originally sold in.

If the boss has no stamping on the top or a big 7 it is a 7:1 head and was probably originally sold outside the United States. If the head has a large 8 stamped on the top (this could look like two '0's) then it is an 8:1 head.

I believe that skimming an 8:1 head thinking that it might be 7:1 can create problems when it comes to refitting it.

Cheers,

Neil