gbohr

I have a converted diesel that I get to start over on because my wife caught the car on fire (long, painful story). Something I've noticed is GM, Ford, and Chrysler are making use of oil squirters to cool down the pistons in their hi-performance engines. They obviously see a benefit that outweighs the additional cost. Has anybody tried doing this on an Olds? Any comments? Is this a terrific observation? Am I a flaming idiot?

I live in an area where 91 octane qualifies as premium (Tulsa, OK) and was thinking this would help against pinging, keep the engine running cooler, etc.

Olds64

The oil circuit inside an Oldsmobile engine is designed from the factory. The only way I know of to modify the flow of oil in an Oldsmobile engine is to put restrictors in the oil galley leading to the heads. Unless you are racing and doing a hi dollar performance build there's no reason to even consider this.

VC455

One way the piston is cooled by transferring heat through the rings. For our Olds engines, that is a major cooling route; windage (oil splash) is another source of cooling. Modern engines have much thinner rings and better windage control; high performance modern engines therefore need another method of keeping the piston cool. That is why they use squirters.

If your Olds engine makes above 1.2 hp/cubic inch and you have thin rings and excellent windage control, you could consider oil squirters. You would need to engineer this feature so that you don't overload the cylinder wall with oil. You must balance the extra oil use versus pump capacity so that you don't starve bearings and other essential destinations for the oil. You would also need to design and add an auxiliary oil cooler.

And after that work, your octane requirement may not go down much--piston temperature doesn't usually get hot enough to change the detonation threshold by much.

I've not heard that car or boat racers use squirters in Olds engines. If it raised power and increased durability, you would think they would have done it.

Faced with detonation, most would reduce compression, cut timing, buy fuel with higher octane, or switch to higher-alcohol fuel (it cools the intake air more than straight gasoline).

But I don't want to dissuade you completely; your proposal sounds like a really cool science project.

cutlassefi

Or just use a thermal barrier coating on the piston tops.
However on your avg carbureted street performance build, most of this would be a waste of time anyway.(Except the Heads).

Duh

Olds designed engines with it. It's a small groove in the rod at the rod cap interface on the rod side. Factory bearings had a small notch at the parting line in the bearings that lined up with the groove.

cutlassefi

Battenrunner

rustyroger

Many small British engines had a small hole in the connecting rod, which lined up with a hole in the top rod bearing to send oil to the pistons, Jaguar XK engines had an oil supply to the small end (wrist pin) journal as Battenrunner describes. Others relied on oil leaving the big end journals getting thrown up the bores. Renault light truck turbo diesel engines had nozzles pointing up the bores sending oil to the pistons.
Having said this, if your engine left the factory without any of the above, you haven't modified it and don't habitually drive with the pedal to the metal, leave well alone.

Roger.