Sorry to confuse the issue, on the EP car we are running a big cam in a higher rpm range. I agree you def need oil just go light wt was all. I have seen problems with heaver oils.
I talked to one of my english guys and he thought there was a either green or blue spring set they used on the race cars (I think they have colored paint spots on them?)
Also he said that there may be a float jet/seat issue and to replace them if in doubt, this was a common problem in the race cars. He has seen them stick when they heat up, also if you have bad vibration (I dont think the L series have much) will cause sticking and overflow (this was on the euro SUs so he was not sure if it applied to the jap stuff). But you def will want a set or two of custom needles.Sam makes good ones!
Good luck!