Oil gallery mods - can too many extra holes causes an issue
Turbo Mini Forums

I have seen under piston oil jets and alignment of holes etc regarding adding oil or more oil to essential places.

My question is, have people had to restrict oil (say to the rockers) or elsewhere because all the extra squirters etc could impact on volume? OR

have people increased diameters of oil gallery parts to improve volume to an area ?

Example cam bearing feed mod plus under piston jets plus increase the diameter of a gallery from 1/4in to 5/16 or increasing size of oil pump 'impellor" --- pressure to some parts suffer????

just thinking it is a fixed volume .. ?

not really needed,

in comparison to a modern engine the oilways are pretty large,

the rockers are (should) already be restricted, as the groove in the cam chain end journel and bearing gves a pulsed feed, if its fed full time the whole rocker box can fill up!

the BMW oil jets we use over here have a pressure valve in the bolt set to about 30-40 psi, so they wont steal oil at low revs,

turbo's dont use much oil,

the only thing I can think of that might cause an issue is oil fed camshaft lobes, but I'm not sure how these are fed, certainly there is a restrictor in the centre main gallery to the cam so it shouldnt be a problem.

most people just stuff in a metro turbo oil pump and thats that.

Keep in mind when revving you are usually dumping a load over the relief valve.

If something is worth doing, it's worth doing half of.

Edited by Sprocket on 8th Aug, 2014.

if you can release oil pressure other than just dumping it to the sump with out costing hp then its a good idea imo

after all you dont need to pump more oil than you can use aside from a small buffer to cater for down the track when the oil clearances grow a little..

thanks for responses people and the new dictionary term for the day. What about these drilled/holed cams feeding the lifters and flanks of cam... same deal, better directed use of the slippery stuff or possibly starve a cam bearing? one pretty well regarded engine builder on the landspeed racer site , blocked up the extra camshaft drillings, in their full on modded NA midget?

well,

cam bearings aren't really worn much normally, unless there's been crap through them and they're scored, for the size of the journels theres not much weight on those bearings.

not sure how much of a difference those drilled cams make, I guess they help make sure theres a clean oil film on the lobe rather than the crap thrown up by the gearbox, I would guess a baffle plate makes as much difference.

also a fair bit of lube will come off the crank from the bearings, that should be clean.

thanks Joe,
Looks like Lots of ' new and improved' products seem to come out without knowing for sure if there is any measurable gain..... in this case it is almost impossible to measure/ against all the other variables ... so not necessarily snake oil but just hard to prove.... Cheers Darryl