4g63 piston oilers, block or not?

[KnightEngines]

Got a new trade customer that specialises in mitsi evo track cars, I've built plenty of Evo 4G63's in the past & with good pistons etc I usually plug the piston oilers on wet sump E85 engines.

My reasoning is that with good forged pistons the squirters are not required & that oil could be better used in the bearings rather than increasing windage & aeration in the crankcase.

Am I wrong to do this? - haven't had a problem in the past, but do not want failures with this customer!

[cjperformance]

Tony , not that i do any 4g63 stuff at all but just in general I dont see any problem with plugging the oilers in that application provided the tune is correct. I would say that the fact you have had no problems says A- Good quality parts properly put together. And B- tuned correctly.

Im interested to hear others thoughts on this aswell.
Cheers,

[KnightEngines]

Yeah, tuner is good & I know how to set them up, but it's something in the back of my mind.

These engines will make 600-650hp (which is not at all excessive) & get beat on lap after lap.

[82c10step]

I plugged all mine over the years. No issues. Also modify the oil distribution block in the head. Try to keep more oil in the pan.

[Geoff2]

Piston oilers maybe more for piston cooling than oiling....

[cjperformance]

Piston oilers maybe more for piston cooling than oiling....

Yes thats exactly what piston oilers are for.

[jed]

I also did a lot of turbo 4g63 and and they were 600+hp. The builder/ tuner always kept the oilers.
He said they were worth HP something about cooling the piston and running more timming.

[Kevin Johnson]

Six years ago... https://www.dsmtuners.com/threads/oil-s ... ff.459718/

god not the oil squirter debate. ...

You would be surprised to know that a Top fuel drag engine runs bearings clearances not far off from some of the built 4g63's. They run around .0035-.0045" on the rods. Those motors cold see 200 psi oil pressure and 160 psi hot.

That's interesting about 160 psi in Top Fuel.

[bentvalves]

i think with a nice windage tray, and even better a nicely done crank scraper they should be left alone.

drag car, sure plug em.

circuit racer, rally, endurance.....run 'em.

[Olds455]

The only time I've heard of them being plugged is on the 7 bolt block in the mains so they don't clog up, pop out, and destroy the bearings and crank. But most people I know of recommend keeping them on the 6 bolt blocks, otherwise.

[NORSK]

Got a new trade customer that specialises in mitsi evo track cars, I've built plenty of Evo 4G63's in the past & with good pistons etc I usually plug the piston oilers on wet sump E85 engines.

My reasoning is that with good forged pistons the squirters are not required & that oil could be better used in the bearings rather than increasing windage & aeration in the crankcase.

Am I wrong to do this? - haven't had a problem in the past, but do not want failures with this customer!

I have built several wet sump engines (not Mitsubishi though) for circuit racing,both N/A and Turbo
Plugging the oil jets makes a difference in the amount of oil that goes out the breather
Never had any piston cooling issues with the jets plugged
Also with narrow skirt JE FSR like pistons,the oil jet tend to hit on the side,almost directly below the oil ring
So they have no cooling effect running these pistons,all they do is flooding the oil ring
With a full round skirt they will have a cooling effect ofcourse,but again it will produce more oil mist
On some engines there are no room for a oil jet either,depending on which type piston used

If the piston crown is really thin and for a serious turbo engine,i would have considered a ceramic top coating perhaps