alex_cristocea

Did anybody installed oil squirters in a 2.5L engine block? I wold like to find out where to drill the holes for the squirters. I made a sketch how of how I think they should be installed but I'm not sure if it's corect. If there is anyone who know what is the correct way to install the and would like to share I would really apreciate.

Raceboy

Same here, plan to install oil squirters.

Your location seems to be ok, you plan to drill and tap the holes yourself?

alex_cristocea

No. The machine shop will do it, but since I can not find anyone who has experience here with this engines I need to make a sketch for the machine shop with what I want. The factors I have taken into consideration when I did this sketch was the piston shape ( which is mahle powerpak) and engine block ( I tried to avoid creating zones with thin material on squirt bore exit area to prevent weakening the block).

333pg333

How modified is your motor and what are your intentions? Are they totally necessary?

951and944S

Wondering, this feature is usually added when trying to lighten a piston for performance because the crown would be thinner, thus more heat.
The 968 pistons are notoriously lighter (had factory squirters), especially the Mahle at 490 grams compared to the 944T at 520. My stock KS 944S pistons at 4mm smaller bore are 540 grams, no piston cooling squirter.
It makes sense that the factory lighter piston probably has a thinner crown and may have needed the oil squirters.
It's definitely not a movement of the ring closer to combustion because all 944 family top rings are pretty low.

Personally, I wouldn't tax the oil system any more than it is if I didn't have to.

If I knew the minimum requirement of the balance shafts at XX rpms, I would plug and orifice the feed to those to limit delivery waste.

The poppet could have a side benefit though, may remove aerated oil before it makes it to the rods.

If you cool the wrist pin, you are also taking heat off the piston and there are some close to free ways to do that.

An escape notch at the upper side beam of the rod would sling 360 degree, already escaping oil from the rod bearing and make it useful.
Drilling from the scraper groove to the pin would send oil directly to the pin on the down stroke.

T

Chris White

If you do decide that these are necessary (and I don't believe they are unless its a full on track engine) then make sure that the head is located inside the oil groove in the block. The head has a flange on it so the hole is not super critical in diameter, the bearing shell will trap the oil squirter in place if it moves. With the right diameter drill bit you could do this with a hand drill (I use a milling machine - but hey, I'm like that!)
Don't fret about the aim - the piton is a moving target and the oil is spraying everywhere.

91K-Man

Hi, All , why not just drill into the main bearing housings, a .5mm hole on an angle . Do not need to make anything. Main bearings are grooved so just need to "hit" the groove. Thats what mantis does when needed.

alex_cristocea

The engine will not suffer heavy modifications. Since I'am rebuilding the engine I thought that the oil squirters will be a good upgrade ( to do while I'am in there) and also I think that a windage port will also be a good thing to do but I don't know how mutch this will weaken the 2.5 engine block. With this build I'am interested most in reliability and longevity first. I will use the car both on street and for some track days.This rebuild started as a "refresh" but after some examination I ended up keeping only the cylinder head and the oil pan from the old engine.
I don't know if they are totally necessary, probably not, after all I know there are track cars without this mods and run fine, but since they cost mostly some machine work and they were also adopted as upgrades by the factory I thought "why not?".

alex_cristocea

The new Mahle piston has the crown 1mm thiner than the original KS piston. It's also thiner than the Mahle S2 piston.

333pg333

I would say as a generalisation more cooling is better...but in your case I wouldn't bother. We had issues on a past motor with oil pressure loss. We're 95%+ sure it was due to too much oil going through the squirters being retro fitted.

951and944S

That's the new Powerpak piston...?

Are those cast or forged..?

T

951and944S

Yep, as I mentioned above, that'd be my fear of using them.

These engines definitely survive hard track duty without them.

Most of my focus is on how I can improve and gain some headroom with oiling, not ways to bleed some of it off....

Restricting supply to balance shafts and using the #3 main to get additional supply to the #2 & #3 rods seems viable on paper.

T

333pg333

Agree, yet it's interesting that they were standard in the 968 blocks so the factory definitely deemed them appropriate.