From: Dave Armstrong - [email protected]
Date: 11 Sep 2002
Time: 07:34:59
Remote Name: 213.122.13.77
Bruce, I'm starting to build a 3 bearing engine up for my Speedex. Popular opinion is to line bore the centre main with the block in place and to use the second main bearing stud as an extra block stud. I've read somewhere that by restricting the oil flow to the cam bearings more oil will be pushed towards the centre main. I even think that the centre camshaft bearing oil feed was blocked and a drain hole drilled down from the valve / spring chest. I was going to put an oversize oil pump on to make sure the pressure is up.
Has anybody any experience of these types of mod or will the line boring do the trick and nothing else is needed? I was thinking of bushing the cam bearings and redrilling down. What size? 1/16" or 1mm or ? I know that Austin decreased the oil jet diameter presumably to hold up the pressure and make more oil go to the centre main.
Is there any experience out there (hopefully good!!) of these mods or what's the best advice?
Thanks Dave Armstrong