Evo 8 drysump bearing clearances

Always a topic on bearing clearances. But how loose do you dare go.

2.2 motor rpm limit 10k

dry sump with auto Verdi oil pump

sequental gearbox

im happy with my main clearances at .0026” tightest and .00265 the loosest.

rod clearances with half std & half HX I get clearances of between .0027-.0028”

if I run full HX I get .00315 - .0032”

I’ll be running 15-50 oil and I’m confident the drysump can flow more than enough oil.

Question is what would you run

1000 bhp 10k rpm limit

Others will be able to advise you, but I'd add - "what oil pressure are you running"? You need it to be high enough to maintain good oil flow to the big ends against the centrifugal force/resistance at the main bearings.

I don't know what sort of oil return you have from the head, and whether it will be compromised by blowby moving against it, but you may wish to run a scavenge wafer from the head if there's a known problem - others experienced with the engine will also be better able to advise on that.

The clearances that you already have are just fine. No need to go any bigger.... Just one comment from my side ( probably you already know it but anyway) - Fluidampr or ATI damper is a MUST to extend the life of mains...