intercooler affect on radiator load (2 Viewers)

[o8ko8k]

waste gate is set to open at 10psi. i could probably back off the fueling about 1/4 turn if needed.

1800-2300 rpm is about 50-55mph in 5th. if i drop to 4th im down in the 45mph zone at closer to 2500rpm.

when i started the thread, i was pretty certain that the intercooler is the answer. Im still thinking so. but im also thinking more cooling somehow would make up for it. any time im on the highway at all, my needle creeps past 1/2 way mark. and i cant keep the boost pressure below 7psi till i slow down under 50. (4.56 and 33's means slow) and fast means hot air down the barrel. add hill and trailer and well, there ya go. (thats my guess anyways). 35" tires should add about 6% and then ill be a little less slow to go places but whats the hurry . The fan clutch lock sounds like a good bang for the buck so i think that may just have to come first cuz its easy.

 

[TheBigBoy]

That's it. A good intercooler.

 

[gerg]

Intercooler placemant is not nearly as hard as you might imagine. Just stick a 3 in core right on top of the engine.

As for the steam pocket thing Dougal refered to, that was my reason for evans coolant. Its boils at 375F so I was happy to trade off higher engine temps that would be free of vapor locked sections vs lower temps with isolated hot spots. I think our cast heads dont move as much as alum ones and dont necessarily tear apart HG as easily with higher temps. An mls is definately better than fiber with this stuff. I think the key to overheating damage is uneven heating once the coolant boils in the hottest areas then you are very at risk for head cracks. There are lots of drag cars that run cemented blocks that just basically overheat evenly and dont suffer that bad in the short term.

 

[o8ko8k]

Intercooler placemant is not nearly as hard as you might imagine. Just stick a 3 in core right on top of the engine.

As for the steam pocket thing Dougal refered to, that was my reason for evans coolant. Its boils at 375F so I was happy to trade off higher engine temps that would be free of vapor locked sections vs lower temps with isolated hot spots. I think our cast heads dont move as much as alum ones and dont necessarily tear apart HG as easily with higher temps. An mls is definately better than fiber with this stuff. I think the key to overheating damage is uneven heating once the coolant boils in the hottest areas then you are very at risk for head cracks. There are lots of drag cars that run cemented blocks that just basically overheat evenly and dont suffer that bad in the short term.

first off, AWESOME! learning, asking, growing knowledge, documenting the process. Thankyou everyone, thats what this place is all about.

I guess sometimes its all about asking the right questions too, which i was struggling with there at the start. I had it in my mind that the needle MUST STAY PUT! untill i backed out of that i was spinning my wheels.

So if i can summarize what i think i learned. The coolant is the limiting factor and engining running temp. The engine can run at hotter temps but the coolant fails at around 245F ish and the engine starts to get hot spots, etc etc etc. so to be safe stick with the 245F thing. To avoid cavitation stick to 220F. or change fluid type.

Now i will guess that engine wear / longevity is also a function of running temp and where the engine to run at 230F everywhere it goes, it will not last as long as one running about at a cool 180F. So yes the coolant is the limiting factor but, this is for the short term use case, not the long term one.

i knew about the evans and the high boil temp and was thinking about moving to that, but i didnt understand the upper limit of what temp the engine can take and I didnt want to add a fluid that would allow me to exceed that which the engine can handle so i decieded to hold off till i knew what that engine temp limit was and how to control the engine to that limit. My design goal was 180F. that probably will not be achieveable. But it gives me somthing to do which was the point of buying the LC in the first place.

Once i felt i could control the temps, then i was going to make the switch to evans.

So one thing i havent found yet about the evans waterless is how well does it work at removing heat and dumping it to air compared to the 30/70 or 50/50 mix of the traditional stuff? That is where my studies have left me.

 

[gerg]

There was some comparative info a while back that clearly showed that evans transfered less effeciently than 50/50 regular. I think it was not a dramatic amount less, but it was less. Something to keep in mind was that if your temp probe is reading 245F, I cant imagine what the jacket right around your exhaust runner or beside your pre cup chamber is temp wise. Those are the hottest areas in the head and once they vapor lock their temp is alowed to climb much higher and the coolant temp might not rise linearly with the overheated area. Your coolant temp gauge is a poor indicator of cylinder head temps. Running an intercooler and leaner air/fuel ratios will reduce the egt temp disparity between your coolant and the hottest areas in your head, reducing the chance of vapor lock.

One reason most folks want low cylinder head temps is for detonation like in turbo gas engines. Those hot areas not only vapor lock and can crack heads, but in a gas engine will cause detonation and destroy the rings and other stuff. This is not a concern for diesels, although running very high coolant temps will stress your engine out in many ways. Shear forces on your head gasket come to my mind right away. I remember when I overheated an engine to 275 when I was running evans and the engine itself was seemingly un affected, but eventually a month later the head gasket blew (fiber gasket). When I pulled the head, the gasket essentially was separated over every square inch of it. It was quite impressive, it was literally ripped apart. There was no sinlge area of failure, but rather the entire things was failing. I really think that is where MLS shines as the layers are designed to minimise shear by sliding and moving over each other.

 

[mudgudgeon]

IMO, engine fan, intercooler and free flowing exhaust, then wind back fueling if necessary.

Also, you commented on 35" tyres adding 6% to your speed over and above using 33"s, this is true, but it will also equate to a 6% loss of torque. The engine has to work harder to get you up to speed and also to keep you there.
It will not be a solution to your heating issues, and could well add to the issue.

 

[ToyRoverlander]

Also, you commented on 35" tyres adding 6% to your speed over and above using 33"s, this is true, but it will also equate to a 6% loss of torque. The engine has to work harder to get you up to speed and also to keep you there.
It will not be a solution to your heating issues, and could well add to the issue.

Sure is. A mate of mine has nearly the same truck as I do but his sits on 35's and is a tad heavier. All his numbers are higher when cruising, EGT, boost and watertemp.

This weekend I lengthened the exhaust on mine as I was getting tired of the insane noise levels of a sidepipe (with silencer). The exhaust now exits at the rear, about 5' of exhaust lenght including an extra silencer. It's whisperquite now.
On the other hand,at cruising speed it increased EGT's by about 30-40C, boost is slightly higher and watertemps are up a few degrees. Even little things can make quite a difference....