Forged pistons also expand when heated. The oil squirters would prevent premature wear on the rings and cylinder walls under extreme driving conditions (i.e. high boost for over 30 minute intervals). There are alot of people who run without squirters (even in a daily driven vehicle) but most of these people are uneducated. The only reason they run without squirters is because someone told them they don't need them (and perhaps they were trying to save a buck). If you compared two identical blocks with forged pistons, one with oil squirters, and one without any type of oil cooling, and tore them down after 30,000 miles of use, guess which block is going to be in better shape? Anyone who has ever studied physics, or any type of engineering would know that the oil squirters would indeed prove to be beneficial (despite the material of the piston!). Talk to any experienced 4G63 machinist, and they will tell you that if you plan on road racing, you want the squirters (even with forged internals).

 

I tell you what, since you think you know more than all of us that have YEARS of experience doing this and have told you they aren't necessary, I'll make you an offer:

I have over 30k miles on my current stroker motor that I daily drive and track occasionally. I'll put up $500 against yours and I'll meet you in NC at a shop of your choice. We can take the oil pan off of my car and look at the cylinders if they don't look as good if not better than an engine with twice as many miles the $500 is yours, if it does then you pay me $500. That's putting my experience against your theories.

Let me know if you want to take me up on the offer.

 

Just because you have a motor with 30k miles and no squirters does that prove they are not needed? Maybe you should call Mitsubishi and tell them they are stupid for installing squirters. They could have saved millions leaving them out. Heck dont stop there call Honda, Porsche, BMW, Ferrari, and any other manufacture you can think of. I am sure they would like to know how to save a buck too.

The answer to this question is. Yes you can leave em out. Is it benificial to leave em in? No brainer Hell yes. What TEC is not gonna take the time to prove to you is that two identical motors save squirters may actually have different knock resistance racing down the highway against the R1.

Look at the design of the evo8 piston. It has a cavity underneath the piston to hold the oil that is squirted onto it. This gives the oil more time to absorb heat before it returns to the pan. Thus controlling crown temp even better than earlier designs.

 

94AWDcoupe owns TEC.
Oil squirters are beneficial for several reason. They have only a single downside: additional cost.

 

TEC. Just because you have a running engine without squirters means NOTHING. NOTHING. N O T H I N G. Just because other people have built engines that didn't blow up without them, means NOTHING. THINK for yourself (instead of believing what others tell you), THINK about what squirters do, and what they were originally installed for. I have been building engines for years. It is so obvious (the laws of thermodynamics stands as proof) that the squirters take away heat from the piston. Maybe this will make things easier to see for you:

diameter of piston rings on a (forged or cast) piston (before startup)

|-------------------|

diameter of piston rings on same piston WITH the oil jets (after it has been brought up to the operational temperature):

|----------------------|

diameter of piston rings on same piston WITHOUT the oil jets (after it has been brought up to operational temperature):

|-------------------------|

diameter of piston rings on same piston WITH the oil jets (after it has been road raced for 30 minutes straight):

|--------------------------|

diameter of piston rings on same piston WITHOUT the oil jets (after it has been road raced for 30 minutes straight):

|------------------------------|

(This is not drawn to scale, it is just to help you comprehend what I am trying to say)

What I am trying to say is, that the piston stays cooler WITH the oil squirters and therefore the rings and piston won't expand as much as piston and rings that have no cooling. If you look above, with or without the oil jets the piston and rings start out at the same size (before startup). However once up to operational temperature (or after it has been raced for a period of time) they get larger, and the piston without cooling gets even LARGER. This is a tolerance issue. The squirters control this tolerance. It is a very very very simple concept, and this what the engineers who designed the 4G63 were thinking. Just think about how how high cylinder temperatures are in this engine! A 2.0/2.3 liter that puts down 270-600 hp? I can gaurantee that your engine would be in better shape now, had you spent the $200.00 to get the squirters installed at the machine shop (ESPECIALLY if you road race, which causes additional thermal expansion). You can keep your money. Can you provide any explanation as to WHY you think they are not needed with FORGED internals? I didn't think so.

 

I don't think he's failing to understand you, just expressing his right to disagree.

One thing that people conveniently forget is that a turbo 2.0L 4 cyl must dissipate heat at roughly double the rate of a 4.0L V8 at the same power level, simply because it possesses roughly half the surface area through which heat is transferred. That being said, a 2.0L with 500bhp is comparable to a 4.0L V8 at 1000bhp.

One forgiving proposition of drag racing is the fact that full power is applied only for a matter of seconds, followed by a prolonged cool-down period. Drag racers need not be as concerned about heat dissipation as road racers, where prolonged heat management is a priority.

Automakers implement the piston cooling oil jets as a measure to reduce the tremendous heat those small pistons must endure over the expected lifespan of the engine (150K+ miles or more). In addition to the cooling action, the jet of oil probably aids in cylinder wall lubrication (especially in a horizontally opposed engine) as well. These attributes are more important for turbo apps than normally aspirated engines, simply because greater power per unit of displacement = greater heat.

I don't know of anyone who can truly advise of the actual difference removing the oil jets may make over the long term, but I'd be far more inclined to retain them as opposed to omitting them.

 

Personally, I like squirters... but not in my motor.

I have seen more failures contributed to a faulty squirter (the check valve fails open, and you loose oil pressure to important places), than failures on a well prepped motor without them. However, most of my expereince is on higher mileage DSM, which would be more prone to some type of failure.

As a matter of fact, I have no experience on a motor that failed because the pistons were not properly "cooled" due to not having oil squirters. I have run without them in my own cars for years and years. I have never had abnormal wear to any of the important places, much of this due to the difference in design of a floating wrist pin, and rod design typically used in aftermarket forged applications.

If you are running a stock rod, stock piston motor, please squirt.

If you are running a good connecting rod and forged piston, feel free not to squirt.

If you are really freaky about this type of thing, and you know you are right about everything (like me, LOL), then do what is right for you! (That's what it's all about, right?)

Have a great day EVO M!

Mike Huml
aka... Slowboy

 

Easy enough. I have friends near by that I have built 2l motors for without squirters. I'll offer you a similar deal. We can meet in NC put your car on the dyno and proceed to add timing till it knocks and then put the other car on the dyno and add timing till it knocks, then we can see which engine (even though the 2l will have a 9:1 comp ratio) which has the higher knock resistance. It will only cost you $500 if you loose.

Oil squirters on a forged component engine is a waste. Only thing that it does is provide a bigger potential to have something go wrong. I've seen it happen. I've seen them drop oil pressure after a rebuild and kill and engine.

 

Really? Then you should take up my challenge, either of them, and take my money, but we both know that it won't happen.

 

I'll say this again. There are much better ways to keep heat in check than having squirters which are prone to failure. I've been building 4g63's for 10+ years. I'm not listening to anyone and I'm saying this out of my own experience.

I'm not going to explain again why I know they are not necessary, all I'm going to say is when do you want to meet up in NC? We can put your theory up against my life experiences.

 

Ummm...you never explained your magical way of keeping "heat in check". You never explained WHY FORGED PISTONS ARE ANY DIFFERENT THAN CAST PISTONS. I am not traveling all the way down to redneck *** south carolina for a dumb dyno test that won't prove anything. WE ARE NOT TALKING ABOUT DETONATION. Why don't you answer any of my questions? Because you have no reason for not using oil squirters. You are just guessing and hoping you are right. Instead of saying oh yeah I have xx years of experience blah blah, why don't you explain why they aren't needed? The truth is, they ARE NOT needed. They are there to just prevent excessive wear under high thermal loads. This is something a dyno test probably won't prove, but who knows maybe detonation is different as well (probably not). You keep arguing in favor of not using them, but provide no explanation.

 

Now you want to compare two different cars in a knock test? WOW just keep showing your ignorance. And just keep leaving important parts out. I guess you run your setups without the oil cooler too. Here in florida oil temps only go up 30-40degrees so they are not needed either.

 

Forged pistons actually expand MORE than cast pistons when going from cold startup to normal operating temperature so you have to run a larger piston to wall clearence with forged pistons. This can result in piston slap and horrible ring seal at cold startup. By running WITH oil squirters you end up with less thermal expansion of forged pistons at normal operating temperature. That means you can run a smaller piston to wall gap when cold avoiding the piston slap, and ring seal issues. Cold start emissions may have more to do with why factory cars are running oil squirters now than actual wear and tear on the engine.

I see both sides of this issue, both setups work.... what ever you chose, realize that you really need to tell the maker of your pistons weather or not you are running with oil squirters, because they should set you up with slightly different sized pistons depending on weather or not the pistons are cooled by an oil jet (or a thermal coating of some kind).

Keith

 

+ 10000000

Yes, so in high heat situations (like road racing) the squirters might prove to be very helpful indeed (with forged pistons) since they obviously expand more than cast iron pistons. I totally agree, both setups work, and there has never been a documented case of a newer 4G63 (or 4G64 block) failing because of oil squirters. The only block with real squirter problems was the 7 bolt DSM block. Why not add them for cheap insurance?

 

I built a 2.4 for my Talon a year and a half ago with no squirters. I used good rods and pistons. So far I have had no problems. I have several long hwy pulls on the engine as well, gotta tune