Underside piston oiling

[canadian]

I have read in articles here and there that oiling the bottom of the piston can be benficial in keeping the temperatures down. So then I came across this nifty buildup here:

For What Its worth, the piston shown was CAST by a Japanese company called ART for use by Toyota in the 93-98 Twin Turbo Supra.

They have been known to produce over 800 HP in these 3 liter engines using the stock cast pistons. Notice the bathtub stopper chain traveling through a hollow "tunnel" in the dome. Oil is squirted in one of the holes and exits the other.

The Honda parts on the right are the ones I chose to use in my SVO. The mounting bolt doubles as the oil feed and favors the 2300 block layout better.

The mounting bolt also serves as a two stage flow regulator.

http://hometown.aol.com/fourced/page18.html

With the jetting installed in the block...

http://hometown.aol.com/fourced/page19.html

To me, it looks like as the piston comes down it will meet up with the jet and have the oil squirted in the hole and back out the other side of the piston. I believe that even spraying on the bottom side of the piston can help keep temps down, but I'm no engineer. Another question would be how to get the oil to the get in the first place...

Just an interesting tech thought.

 

[leroy]

I've heard of this before also. You can't argue with results.

I think ceramic coatings on the piston can help accomplish the same thing (lower piston temperatures). It seems like you would also need to run water injection with the coatings to keep them clean and prevent deposits.

One of these days, we'll see what Brian Dourty's truck will do with the coated pistons.

Jim

 

[BillC]

Starting in the 1970's, Porsche put oil squirters in all the 911s, as well as all their racing vehicles. These sprayed oil on the bottom of the pistons. Works like a champ, does a great job keeping temps down, just not a new idea.

 

[nightdiver]

I have seen an engine from a MAN 422 diesel truck that they forgot to install one of the oil injectors and the piston melted.
Its a cool thing to do but you have to upgade the volume of the oiling system and i dont mean just the pump.
I would do it with a dry sump

 

[just a 6]

Cools the piston

Cools the piston

Most turbo engine manufactors install oil squirters in there turbo blocks, like Mitsubishi, Toyota and many more including Chryslers Turbo Neon (SRT-4). I'm really supriced that PAS did not do that but i think it's because you need a oil channel in the block where the squirters are located, and i'm not sure that our 4.3 blocks have that. The next block i'm building i was going to look in to if i can install squirters on it. It's really good for keeping the piston temp down.