More MG Skunk Works secrets revealed

[Bret]

Question about your rockers: are they the ones that have been available on ebay and did you have to do any mods to them. I have a set of them and a loud tick which I suspect might be a worn rocker arm and was considering replacing them.

Actually I did get the roller rockers (1.5:1) on ebay. No modifications just slip them on in place of the regular rocker. But I did replace the old rocker shaft and when I have the head off to make way for the alloy head I’ll make sure to check that the exhaust valve doesn’t hit the block at full lift. Theres suppose to be a bore cutout to accommodate the exhaust valve. But if there isn’t I’ll have to figure out my clearance.

Another thing to check is if the valve springs are binding at full lift. Peter Burguess’ book “How to Power Tune MGB 4-Cylinder Engines” recommends that a 10thou clearance between each coil of the spring at full lift. The good news is my alloy head has a nice set of heavy duty double springs. But I’m going to check them just the same.