coolant passages??WTF?

[jagpride]

"Don't have any problems" is a terrible excuse. If you'ves seen the systems they use to tune each cylinder (usually EGT sensor and I've seent ehm run widebands on each one) to get everything running correctly.

-I never heard of that : (

The point is they would NOT be running at a constant temp, why you think you know better than the company that spent millions on designing the engine is beyond me...

Because i got an A in Geometry jk I never said i knew more than Toyota.Thats why i am posting



-Power steering is where it's supposed to be (seen any of the earlier M engines?).
-Same thing here, look at a 2JGE, a FFIM works best with forced induction, which was designed first?
-Thermostatic controlled oil cooler isn't as reliable as pressure based.

I was replying to adampecush quote where he mentions "Heat Transfer"
-I dont see how running the power steering reservoir close to a hot engine is good?
-again talking about heat transfer 7mgte intake pipe on top of the engine = nice heat soaking is that something good?; )
-Were did you hear this from?Many people run thermostatic oil coolers with no problem there's a whole thread on that matter in the oil section of our forums.

I not shiting on Toyota so I hope i am not offending you and others.I love Toyota!!! <3<3 I was just trying to prove a point as far adampecush quote

 

[Poodles]

- The power steering res. gravity feeds the pump, doesn't matter where it is for the most part as long as it can do that.
- Look at the evolution of the M engine designs. The central throttle body was done for a reason (same reason it's done on the 2JZ-GE)
- Yes, people run thermostatic coolers. Like most upgrade parts they aren't designed for 100K miles like the OEM's have to design products for. If you want to see how reliable t-stats are, look how often your cooling system's t-stat goes out...

 

[gaboonviper85]

Poodles....stop using logic...peeps just dun understands yo:-(

 

[jagpride]

-You have a point as long as it works fudge it

-Whats the reason for the central throttle body?I am also talking about the 7mgte not the 7mge or the 2jge.

-As far as the t-stat mine hasn't messed so i realy dont know what to tell you.one thing to point out tho Mazda oil coolers use a t-stat and they are very reliable many ppl swap thos in with great results

 

[IJ.]

- The power steering res. gravity feeds the pump, doesn't matter where it is for the most part as long as it can do that.
- Look at the evolution of the M engine designs. The central throttle body was done for a reason (same reason it's done on the 2JZ-GE)
- Yes, people run thermostatic coolers. Like most upgrade parts they aren't designed for 100K miles like the OEM's have to design products for. If you want to see how reliable t-stats are, look how often your cooling system's t-stat goes out...

Simple fact that all Oil T-stats are 90/10 designs mean that even if it fails it's not a show stopper like a coolant T-stat.

Pressure based system is cheaper to produce, don't kid yourselves that there's any other reason they went that way, save $1 per car over it's model life in a couple of areas soon adds up when building on that scale.

As I said in an earlier post the uneven/mongy holes are more than likely done to control the temp from end to end and across the block, later engines may have a lot of cast in restrictors/directors to achieve the same result, the JZ's are an evolution and around that time there was a leap in technology.

 

[jagpride]

So in short words?Don't fudge with those coolant passages right?God its so temp thing to bore them out!!!!

 

[IJ.]

So in short words?Don't fudge with those coolant passages right?God its so temp thing to bore them out!!!!

If you don't have the means to measure temp changes along/across the block I'd leave them alone you could do more harm than good.

Same reason I don't support the mod that drills the hole at the back of the head that's blank, I don't "know" what the net effect is and have never seen any data that supports it being a good/smart thing to do.

"If it's not broken don't fix it"

There are a few areas that can be improved with a little effort in the 7M cooling system but randomly drilling passages isn't one of them, I ran an electric booster pump as I found the stock pump would barely move water at a slow idle and then would cavitate it's brains out at high RPM causing stem pockets in the rear of the head.

 

[spinyard]

link to said booster pump?

 

[IJ.]

link to said booster pump?

Link

 

[TurboStreetCar]

Witch model were you using Ian?

 

[IJ.]

Witch model were you using Ian?

110 Dan

 

[Jeff Lange]

Newer Toyota engines where the cooling jacket around the cylinders is completely open have plastic water jacket spacers that fit around the cylinders to control water flow, etc.

It's been covered multiple times in this thread, but I'd just like to reiterate that simply having the most coolant everywhere is not what you want to do.

Jeff

 

[TurboStreetCar]

110 Dan

Just to verify the 110 is 24 volt? Did you mean the 115? Or did you run the 110 at 12 volts?

 

[IJ.]

Just to verify the 110 is 24 volt? Did you mean the 115? Or did you run the 110 at 12 volts?

110's come in 12v.

 

[northwestsupra]

110 Dan

looks like an ebay turbo, ian have you been shopping ebay. jk ill have to keep this in mind if i run into water pump problems

 

[TurboStreetCar]

Its a turbo for the cooling system.

Thinking of doing this.

 

[supradjza80]

lol, do you think these engines were engineered by somebody in a back yard, with no understanding of heat transfer and fluid mechanics?

No, I never said that...Maybe you do not understand why having the water jacket uniform around the piston is desirable. Regardless of flow through the narrow gasket openings having a uniform thickness of material with a uniform water jacket is more desirable as it helps eliminate hot spots in the block because water (which is an excellant heat sink) is uniformly present around the cylinders.

And yes they also need to know the flow and temperature gradient throughout the coolant passage ways/block but having a uniform coolant jacket is better...This is why many engines are open deck allowing for the most uniform coolant jacket possible (this is not desireable as far as I know for forced induction motors as the seal is normally not as strong, we 7m'ers all know about that )

example of an open deck block

EDIT: Just an FYI, I have never seen nor cut a 7m block before to check the casting passage ways, due to this the inside of the casting COULD have a uniform water jacket around the piston, so Maybe even thought the deck surface opening is not symmetrical, the passages still may be done this way. I haven't checked and do not care to check but as I stated above a more uniform water jacket is always more desirable.

 

[IJ.]

7M is siamese bores Dave.

 

[supradjza80]

Ummmm... look at a 2J headgasket and say that again

Right, so the gasket has small holes for flow control, that still does not take away from the fact that having a uniform coolant jacket around the cylinder is more desirable, and definitely appears to be what the 2jz is closer to having than the 7m. Water is a much better heat sink then cast iron.

---------- Post added at 01:54 AM ---------- Previous post was at 01:53 AM ----------

7M is siamese bores Dave.

I am aware that the 7m is not open deck...It was just an example of as uniform a coolant jacket as you can get. I am aware that between the cylinders is going to be an inevitable hot spot on the cylinder as there is not water there.

 

[IJ.]

No no not open deck/closed deck the bores are actually all interconnected so there is no coolant flow around individual cylinders, everything goes up and over.