[dreamin]

Water does expand as temperature increases even before boiling and can rupture steel pipes. Having said that, for the amount of water in the system and using materials that have stretch (plastic jug, rubber hoses) you'll probably get away with it for testing. Other way to think about it is to consider if the pressure does increase too high what will rupture and what's the impact of it.

I am thinking of just routing the hoses into a 5 gallon jug with a lid, but no cap. So there would be no pressure.

 

[!Peter!]

I am thinking of just routing the hoses into a 5 gallon jug with a lid, but no cap. So there would be no pressure.

I'd only half fill the jug and poke a small hole in the top so that cap doesn't pop off and coolant doesn't overflow.

By the way I like your approach and am watching as I'm planning on compounds in the future and an air to water intercooler like you're doing would be perfect!

 

[dreamin]

I'd only half fill the jug and poke a small hole in the top so that cap doesn't pop off and coolant doesn't overflow.

By the way I like your approach and am watching as I'm planning on compounds in the future and an air to water intercooler like you're doing would be perfect!

I hope to get to it this week. I got a lot going on. I will probably just use plain ole water. I’m really courious how hot the water will get.

 

[boomersrule55]

Have you checked out frozenboost.com ? they have a lot interesting things going on for air-water aftercoolers...

 

[dreamin]

Have you checked out frozenboost.com ? they have a lot interesting things going on for air-water aftercoolers...

I just looked now and the kit for the 350 hp has a intercooler that looks exactly like mine. Their radiator looks to be twice the size of mine. So it may be that I’m undersized in that area. I wish I had known about them before, I would have just bought that complete kit. I may still buy the radiator although I’m tight for space.

 

[!Peter!]

As a thought, these may help get additional cooling capacity in a tight space 10'', 14'', 17'', 20'' or 25'' Single Pass Clear Anodized Heat Sink Coolers . You could mount that along the chassis rail and plumb it so that the coolant goes through that before the radiator.

 

[Dougal]

I just looked now and the kit for the 350 hp has a intercooler that looks exactly like mine. Their radiator looks to be twice the size of mine. So it may be that I’m undersized in that area. I wish I had known about them before, I would have just bought that complete kit. I may still buy the radiator although I’m tight for space.

How big is your intercooler radiator?
To get similar heat exchange to an air/air you need to be even bigger. Reason is you've got two stages of heat exchange so each needs to be more efficient so the total can be good.

Air/Air 60% heat loss is easy. Air/water needs to be 80% and then water/air 80% to make similar numbers (0.8x0.8=0.64 which is 64%.

 

[char1355]

If you look at the late model Ford diesels that use water to air intercoolers, the radiator for those is huge. It's core is like 40"x 21"x1.75" and those engines are in the 475 HP range. That intercooler radiator is literally bigger than the engine cooling radiator. And there are aftermarket upgrades that are even bigger. Mostly in thickness and cooling tube area. That is one area of cooling on a diesel where there is no such thing as too much.

 

[dreamin]

How big is your intercooler radiator?
To get similar heat exchange to an air/air you need to be even bigger. Reason is you've got two stages of heat exchange so each needs to be more efficient so the total can be good.

Air/Air 60% heat loss is easy. Air/water needs to be 80% and then water/air 80% to make similar numbers (0.8x0.8=0.64 which is 64%.

Mine is only about 6” by 12” with two fans. It does start with the water from the cool side of the engine rad, so that helps I guess. (Maybe not)

One thing about a separate system is it could cool down in cruise. For example, if I’m going 60 on flat ground, my boost might only be 5 or 6 psi. So the intercooler radiator could be cooling down the resivour. Then when I hit the throttle for a hill, it would have some cooling in storage. When I start with engine coolant, it’s always gonna be a 150 degrees or so.

Still haven’t got anything done yet. Too many alligators to wrestle.

 

[dreamin]

Up date,

So I decided to do some testing on my intercooler in effort to lower EGTs. First I drove down a local road to get a baseline EGT. I was going about 60 mph and the EGT went to around 1000 for a short time and then slowly backed off to about 900. I did this with a cold truck. The course was 1 mile of dirt road at 30 mph and 3 miles out and back on a two lane black top. When I turned around and excellerated, it went back up to a 1000 and then down again as I just cruised. It never went below 800 and the water temp was up to 210 at the end of the run.

I removed the cork gasket in my intake system. I feel that cork is not appropriate, but the gasket looked fine and I don’t believe it was leaking any boost.

I made a new gasket from that blue material you see.

Next I cleaned out a five gallon bucket and drilled a couple holes. That and some heater hose gave me my test kit.

I had installed some cut offs on the intercooler set up last time I worked on it. They made it easy to do this without draining the whole radiator.

Then it was a simple job to unhook the hose from the suction side and return side of the pump and plumb the five gallon bucket in and separating the whole system from the radiator. This picture shows the setup in the back of the truck.

Obviously, I spilled a ton of water getting the system primed and pumping. I also got a mouth ful of coolant. I can say I would rather drink gas than coolant. This was very difficult and I wonder if it was ever primed before. That pump loses its prime in a NY minute.

On to the test. Again, the truck was dead cold and the temp outside was pretty close to the same as the baseline. I put about 4-5 gallons in the bucket. I drove down the dirt road slow so I didn’t upset the unsecured bucket. At the end I stopped and checked that it was fine.

I headed out on the black top briskly to 60 mph. The EGT went to 1000 again at 17-18 inches of boost. I stumped the pedal for a brief period and got the EGT up to 1300. Let it slow back to 60 and the temp went back to 800-900 just as before. I turned around and repeated the return trip. When I got back to the dirt road I noted the water temp was 200-210.

Before driving back the mile to my house, I climbed in the bed and felt the bucket. To my surprise, it was hot as hell. I’m not saying you couldn’t touch it, but you weren’t going to lift the bucket with your wrists “Kung Fu” style. (for You young kids that don’t know what that means, it was hot) I crawled under the truck and felt the intercooler radiator. It was blowing warm air out. I drove back to the house and got the lazar temp gun out. The bucket was 120 degrees, but it felt like it cooled some from earlier. (Not any boost heat on the dirt road)

So now what to make of this?

 

[eggman918]

I have a couple of observations from my air to air setup, in the winter when it's in the teens/twenty's under low loading with the heater on the thermostat almost never opens fully for me. However when pulling a interstate grade at speed my coolant temp will quickly reach 210/220 and just bas quickly drop after the crest, that tells me that the amount of heat removed from the charge air and passing through the radiator is substantial for it too affect the coolant temp that quickly.

 

[dreamin]

I didn’t realize that much heat was made there. I plan to do a longer test drive. I kind of afraid to just drive a 1/2 hour straight. Maybe the water would start melting the bucket. It would appear that my intercooler radiator is too small. Even so, the EGT went to 1000 when the water must have been cold. That doesn’t really make sense. I’ve heard that it’s not hot unless you see black smoke. My exhaust comes out high on the pax side. My pax mirror looks right at it. The only time it is a little black is when I’m right on the floor and the EGT says 13-1400.

 

[eggman918]

I didn’t realize that much heat was made there. I plan to do a longer test drive. I kind of afraid to just drive a 1/2 hour straight. Maybe the water would start melting the bucket. It would appear that my intercooler radiator is too small. Even so, the EGT went to 1000 when the water must have been cold. That doesn’t really make sense. I’ve heard that it’s not hot unless you see black smoke. My exhaust comes out high on the pax side. My pax mirror looks right at it. The only time it is a little black is when I’m right on the floor and the EGT says 13-1400.

1,000* pre turbo under acceleration is OK and 700* +/- 50* cruising on level ground is about right with "bricks" like you and I have...$.02

 

[char1355]

Yes, your EGT is unusually high. 1300-1400 is in the danger zone. 1000 at cruising is way above normal with your low boost level. Several possible causes. One is too much fuel but you're not seeing a black cloud out back all the time so that's not a likely suspect. Second is pump timing is retarded which will create more heat. And third to not enough cooling capacity in the intercooler system which is the prime suspect. When under boost, that air gets very hot very quick. 300-400 deg F are quite possible. When your boost was 17-18 PSI that is about a stock engine level. Engines turned up to around the 200 HP level are going to hit around 30 PSI.

 

[dreamin]

More data,

I drove out to the black top. About one mile of dirt. I kept the boost 2 psi or less. I checked the bucket temp with my lazar gun.

79 Degrees. I drove 4 miles at 60 mph. Checked the temp again.
108 Degrees. I drove back the 4 miles. Checked again.
130 Degrees. Repeat the 4 miles.
140 Degrees. Repeat.
148 Degrees. Repeat.
150 Degrees. Repeat.
152 Degrees. At that point, I figured it wasn’t going significantly higher, so I drove back to the house. When I got back, I checked one more time and it went down to 133. It seemed like a short time for it to go down that much, but I guess there’s not much heat at low boost. Question for anyone, does a turbo diesel intake manifold ever go in to vacuum? If it did, would the intercooler be getting cold?

As far as this test, funny how the highest temp is about what I figure the cold side of my radiator. It would seem that both my intercooler and it’s radiator need to be bigger. The IC I have is taking heat out, but not enough to effect the EGT. The very first run when it was 79 had just slightly lower EGTs. After that, they were pretty constant.

 

[boomersrule55]

diesel motors do not create vacuum as they have no throttle valve... rpm and hp and controlled by the amount of fuel injected into the cylinder... the turbo charged diesel motor is a marvel and is the most efficient internal combustion motor ever created... imo 😁

 

[char1355]

In your driving test, you see the water temperature in the bucket slowly rising. Now imagine that if you had that much coolant in a radiator to cool it down it might never rise much over 100 deg or even less. The trick is you want the intake air to be cool but the engine coolant temp not too cold. The 4bt that had the water aftercooler used engine coolant which limited the cooling ability. Newer engines use two separate radiators and cooling systems. This is often a problem when fitting a system to an older vehicle in trying to find room for 2 radiators. Also, with water to air unit the efficiency of the heat exchange unit can vary by design. Many of the aftermarket units are designed for gas engine applications where boost level is much lower. They often rate them on HP which doesn't really tell you anything. Need to know how much heat they extract. You're taking a good scientific approach to see where you problem area is.

 

[dreamin]

1,000* pre turbo under acceleration is OK and 700* +/- 50* cruising on level ground is about right with "bricks" like you and I have...$.02

Im wondering if there’s a correlation between boost psi and EGT. What I mean is at 15-17 psi, I’m running 1000 degrees. It doesn’t matter if I’m on flat ground excellerating or climbing a hill at a study speed. When you guys have 800 degrees at cruise, what is your boost psi?

It appears that my pedal is linked to the boost psi and that is linked to the EGT. Maybe I’m fighting a losing battle to lower the EGT in cruise because it just takes that much power to drive my truck in cruise.

 

[eggman918]

It seems truly load based for me around town and on trails I spend a lot of time below 1,500rpm and making 6-12 psi and will see 900*/1,000* and a slight haze.
AT 65mph on level ground it will be turning 1,800rpm and I will see 22/25 psi and 800* +/- 25* pushing my rig beyond 65 requires a lot more running 75mph is 2,150rpm and requires 25/30psi resulting in 950* EGT's +/- 50, and I pay a 2mpg surcharge for that 10mph.

 

[char1355]

At 1800 RPM you engine is at it's peak torque and running very efficient so your EGT is lower.