Heat exchanger discussion

JERMzSS

Well-Known Member
I see alot of questions with alot of good anwsers spread around but i was hoping we could start gathering this all up in one place.

Adam had told me about him and his dad using a donors heater core as an exchanger and it didnt sound like it worked as well as they liked. Its understandable considering it will barely hold a glass full of water.

I did some quick testing and it cools water down very well. I got hot tap water and filled up 2 glasses. Poored one into the heater core and held it in front of a box fan for 1 minute. Afterwards I poured its contents back into the cup and compaired it's temperature with the glass l left sitting on the counter for 1 min.

Water from tap into 2 glasses - 135 degrees.

Water in heater core after 1 min in front of box fan - 85 degrees

Water in glass left on counter - 125 degrees.

So the biggest problem is volume with using a heater core. Does anyone think maybe stacking 2 or maybe 3 heater cores and running the water in series through them with a fan would be worth the time and money? The only place i can see to mount them would be under the radiator inside of that 9"x12" boxed in area facing down. The fan can pull cool air from under the car. I know it's not the most ideal spot but it's the only place that seems like cool air can be drawn in.

Anyways whats y'all thoughts on this? Dumb? Waste of money/time?Lets get some info in here.
 

TheNuker

Goblin Guru
How much of that heat was soaked out of the water simply because the heater core was much cooler than the water in the first place? I bet it was quiet a lot.

I'm going to get rid of my front mount 12 inch square and rear mount with air scoops a 24x6x3" unit in the back under the spoiler mounts.

Nuker-
 

JERMzSS

Well-Known Member
Crap i forgot to add that that was a concern of mine so i let the empty heater core set in warm water for a few minutes to bring its temp up.

Not to say that it didnt cool back down some before the water was added but i got the chill off of it for sure.
 

Andy

Well-Known Member
I mounted my heat exchanger in the spot you talk about in the front by the radiator. It is not ideal but the extra coolant in the system and the radiator should be plenty of cooling capacity, especially after the dual pass end plate and the phenolic intake spacer. The downside to mounting it up there is the tunnel is now full of coolant lines. I would prefer a rear mount radiator by the engine if a good heat shield is made for the exhaust and if a good duct could be made to pull fresh clean air over it. A couple of guys have made some good duct and heat shield designs on here.
 

Brian74

Goblin Guru
I’m now kicking around diferent ideas for heat exchangers. I think with the turbo cars, the liquid air intercoolers are probably a bit more efficient at avoiding heat soak vs. the SC cars. Unfortunately so few turbo builds on here so far to see opinions.

I still am not 100% on mounting the HE up front, because the heat from the radiator makes that location well above ambient and I dont want water lines running through the tunnel. I do not want to mount anything to the rear of the cage, either.

With the heat exchangers, I have read that efficiency is affected by:
Airflow /ambient temps (obvious)
Volume (surface cooling area of the HE)
Capacity (more water will result in better cooling efficiency)

So far I cannot find anything that recommends what HE surface area, capacity or configuration to use on a turbo car liquid to air cooler application such as this.

I wanted to originally do pods like the Atom 3s, but the fabrication looks like it would be a total nightmare. Right now I am toying with the idea of a pair of 11x10 (or slightly narrower) heat exchangers mounted vertically on each side behind the seats, facing outward. These would be below the rear cowling, right above and aft of the fuel tank. The 10” height matches the frame rails, so mounting would be very clean. On the right side I would have to redirect the engine coolant hose slightly forward to make clearance. A simple 14 x 10 induction scoop could also be made for them, with baffles to direct the airflow. I think just the volume of water circulating and using quality fans alone would be effective. I would run a high quality, high CFM shrouded puller fan on the inside of each that would pull the outside air through them.

I an also thinking of going with the B&M fluid supercooler. These are great quality and were originally designed as automatic transmission coolers. I called B&M and they confirmed that this cooler would work fine for my water application. They even already come with 1/2” fittings.

Thoughts?
 

Briann1177

Goblin Guru
I'm not sure which B&M cooler you're looking at, but the couple I saw on Summit Racing look to be very similar to the one DF provides.

The DF provided heat exchanger fan is set up to pull air from under the car and up into the area behind the radiator. With each fan pulling air into the same area, I wonder how that will affect efficiency.

I think the only way to keep track of cooling performance is to monitor the IAT. I did a lot of back and forth, but I finally decided that it would be wise to invest in an Aeroforce gauge for this reason. Something you might want to look into if you haven't already.
 

Brian74

Goblin Guru
I think the cooler DF gets is from frozen boost. I prefer the B&M due to excellent quality reputation and I know for a fact it US made. May even go with a Derale cooler, but not sure they make one small enough.

After riding in Rich’s Goblin, it is clear to me that the front of the car is extremely warm due to the radiator. We already see 100 plus temps here in summer. I also read a few people in here mention they had better IAT’s once they relocated. A few additional concerns for me with that location are debris impact, and dirt / road grime being pulled into the fins.

I do plan on an aeroforce. I hope it can read the IAT 2 temps. So far my scan gauge only reads the MAF IAT temps, which is frustrating.
 

TheNuker

Goblin Guru
Just as an FYI, I switched from a front mount heatexchanger because of this....


My front mount heatexchanger I was seeing IAT2s up into the 180s on hot days (mid to upper 90s), and that is with a new functioning pump. That is the reason I switched to back mount and much larger now I'm down in the 90s low 100s (or 110s on the last 95deg day(when I'm pushing it for an extended time.

And keep in mind the 180s IAT2s were with the stock pulley, and the 90s-100s are with a 2.8"

Nuker-

I wanted to expand and say that I think a part of the reason front mount was sucking a lot of the heat from the radiator. And that system is a heck of a lot hotter then the intercooler system.
 

ctuinstra

Goblin Guru
I do plan on an aeroforce. I hope it can read the IAT 2 temps. So far my scan gauge only reads the MAF IAT temps, which is frustrating.
I can assure you it does monitor the IAT2 temps. I have one. It's interesting to monitor the temps realtime. I noticed with the throttle closed on a long downhill, they would rise (because of lack of intake air), and then as soon as I opened the throttle, they immediately start to come down.
 

ctuinstra

Goblin Guru
I'm sure you have seen my set up and I understand some don't want the HE mounted up high in the rear. But one thing is for sure, it's overkill as far as I can tell. The HE never even gets warmer than ambient air. I couldn't be more happy with the results of it. Point being, you probably don't need as much as you might think as long as you get good airflow.
 

Brian74

Goblin Guru
I'm sure you have seen my set up and I understand some don't want the HE mounted up high in the rear. But one thing is for sure, it's overkill as far as I can tell. The HE never even gets warmer than ambient air. I couldn't be more happy with the results of it. Point being, you probably don't need as much as you might think as long as you get good airflow.
Yes, you're running a 26x7 (with no fans?) I am leaning heavily towards a 10x10 to 10x13 Derale Atomic Cool. Looks like I may only need 1. These things are designed to be mounted anywhere and will fit where I planned. They already come with a shrouded fan that pulls 600 CFM. My buddy ran this same style cooler in the back of his dragster he and said it works great; he actually went to a smaller one.

I am also thinking of running a Varimax CTS-V style coolant pump, which flows 25% more GPM than the Bosch pump

The fan on this cooler will pull more amperage and so will the pump, but since I am running an SC fuse box, I will run the fan and pumps on their original seperate circuits.

I am debating on running a ~2 qt aluminum resorvior at a higher mounting point to add some static fluid capacity in front of the pump and automatically alleviate any trapped air in the system. So far there is only one I can find with two 1/2” NPT fittings, otherwise I’ll have to drill and tap a larger upper fitting.
 

ctuinstra

Goblin Guru
Correct, no fans. I don't see any need for it. While at stop or very low speed, little to no heat is developed since there isn't any boost. The reserve capacity of the system and hoses more than make up for it. Now, if the HE was mounted where it wouldn't get good airflow, that's a completely different story.
 

TheNuker

Goblin Guru
A HE that works well on a dragster that has to do it's job for 10 seconds might not work great for a car that could be in the power for who knows how long on a track or hard street driving right?!

Ultimately I like the idea of 2 fanned heat exhangers mounted in nicer looking area and I might go that route eventually. But for now the large ZZP HE works great without a fan.

Nuker-
 

DanPerryy

Well-Known Member
We would pack the HE on a drag car with ice. It needed to be cold for just a few seconds. For our Goblins we need a HE that will dissipate the heat from the compression of the air constantly. With any HE, there will be some rise in temperature from the hot input to the cooler output. Perfection (with using ambient air to discharge the heat) would be that the temperature of the output of the HE would equal the ambient temperature. Perfection is not possible but having the output as close to ambient is all the better we are going to get (unless we use ice like a dragster).
 

Brian74

Goblin Guru
The point isn’t whether or not it works for a dragster; he was using his HE for an entirely different purpose, fluid and temperature range. The point is that these HE’s are specifically designed to work efficiently in confined spaces lacking direct forward airflow.

Fortunately for me, as I mentioned earlier, the turbo cars appear to be more efficient at avoiding heat soak using these liquid to air coolers (above the valve cover) thus will not requre as much additional HE as the S/C cars.
 

DanPerryy

Well-Known Member
And my point was the sinking of the heat that is created in the compression of a gas - air in this case - must be dissipated to ambient.

In a track car is does no good to sink the heat temporarily, we need to dissipate the heat to ambient. The closer we can get to having our intake air to ambient temperature the more dense the air will be and the more fuel we can add to it to make more power.

I have talked to some who do not recognize that the heat created must be continually dissipated or they will fail to maintain the lowest possible intake air temperature. Heat must go somewhere and the only place we can put it is to the ambient air.
 

ctuinstra

Goblin Guru
Sounds like all of us are pretty well versed on how the intercooler systems works! That's good! I've been on ATV forum where everyone thought that they knew more than the engineers that designed the machines, especially when it comes to the cooling system!

The HE system is one area of the Goblin that lends itself more to the owners interpretation of the best method of a set up. This is not one area where most will not "follow the instructions". I find this interesting to see others design and build.
 

dperkins

Well-Known Member
I feel like I will be running something like ctuinstra with the HE behind the seats above the engine. That is the pretty much the only viable option I can see for mine with the setup I have. Maybe I could mount it like BAR-AIR but I am afraid of my cats heating up the exchanger really quickly.
 
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