High IAT2 temps and KR

Tim Moland

Well-Known Member
I think your problem is the intercooler. I believe its only rated for around 350 hp and since you have the z54 I'm guessing you are right around that. I upgraded my heat exchanger to alot larger one with a fan and my iat2 usually runs about 15 degrees above ambient but sometimes up to 30 degrees above if I am driving it hard for awhile. I have the zfr 6758 so it's the same size turbo you are running. Frozen boost has a type 10 intercooler that is rated for up to 600hp. It's the same shape as the stock one only larger. I think that the one I will be switching to, looks like it will work with minimal modifications to mounting bracket. Here is my heat exchanger, I still need to add a side scoop like some others have done here but I am hoping that a larger intercooler will solve my issue View attachment 20619View attachment 20620
I like your fill cap on your intercooler, but I can't help but notice that the top is below the top of the intercooler. How do you plan on getting out all the air out of the intercooler? The high point looks to be the intercooler.
 

Christopher Sanchez

Well-Known Member
I have the same problem with intake temps with my stock turbo (no ducting) just fan, on the heat exchanger stock location. I recently installed a spal fan on the heat exchanger and ran the intake filter outside frame to catch more fresh air I was surprised how stagnant the air is in the stock air filter location (with the windshield installed). I have been unable to test the changes to see if any improvements have been made as I am currently installing a new Mr2 shifter but am afraid that it will not be enough. I agree with ross I have always believed that the turbo setups created more heat. Either way sounds like there is room for improvement regardless of engine. When running the 1/4 on a 80ish degree night (stock air filter, stock fan) I was seeing 150-160 iats displaying on my rpd screen. The car was noticeably down on power after the 1/8th. Next time I take the car out I hope to take a scan tool with me to collect actual usable data. Seem like installing a larger heat exchanger in a location that gets more airflow is the way to go. I was under the assumption that the intercooler pump that comes with our kit was the exact pump that zzp sells?? I thought the part numbers were the same but I could have made that up.
 

Tim Moland

Well-Known Member
I have the same problem with intake temps with my stock turbo (no ducting) just fan, on the heat exchanger stock location. I recently installed a spal fan on the heat exchanger and ran the intake filter outside frame to catch more fresh air I was surprised how stagnant the air is in the stock air filter location (with the windshield installed). I have been unable to test the changes to see if any improvements have been made as I am currently installing a new Mr2 shifter but am afraid that it will not be enough. I agree with ross I have always believed that the turbo setups created more heat. Either way sounds like there is room for improvement regardless of engine. When running the 1/4 on a 80ish degree night (stock air filter, stock fan) I was seeing 150-160 iats displaying on my rpd screen. The car was noticeably down on power after the 1/8th. Next time I take the car out I hope to take a scan tool with me to collect actual usable data. Seem like installing a larger heat exchanger in a location that gets more airflow is the way to go. I was under the assumption that the intercooler pump that comes with our kit was the exact pump that zzp sells?? I thought the part numbers were the same but I could have made that up.
They do sell the stock Bosch pump. But they also sell their "high volume" pump, which looks like the Bosch pump with their own turbine housing on it. It is supposed to pump an extra gallon a minute.
 

Gtstorey

Well-Known Member
Positive displacement superchargers at the very least will suffer from heat soak since they set on top of and are directly bolted to the engine so when they are sitting after they are driven or on multiple dyno pulls without good air circulation they will heat up more than other FI type systems.

As someone that deals with pumps on a regular basis, the head loss through the many feet of pipe that this system has means that the stock pump is moving the water much slower than it would in the typical front engine, front heat exchanger system. I'm starting on the intercooler set up on mine this weekend and will likely run 2 of the stock Bosch type pumps in series if I use the stock heat exchanger in the front.

I have a stock Camaro ZL1 heat exchanger I may see if I can find a way to mount, but the surface area is much larger than I think I have seen anyone else mount, so I don't know if I can fit it in anywhere.
 
Last edited:

Justin

Active Member
I like your fill cap on your intercooler, but I can't help but notice that the top is below the top of the intercooler. How do you plan on getting out all the air out of the intercooler? The high point looks to be the intercooler.
Honestly I never really realized that. I feel kinda dumb. I just thought it was at the height of the intercooler inlet and didn't realize that it needed to be above it. Thanks I'm going to have to come up with a different fill solution
 

Justin

Active Member
I would love to go this route. In fact, this morning that was the plan, until I went out and looked at my car. I'm using stock seat belts and I have no room to move the fuel tank over.
I am using 3 point seat belts too. I bought a new set from seatbeltsplus.com they sell some that are smaller in size belt retractor that will fit. I did have redrill one of the holes on the belt retractor but it fit
 

ctuinstra

Goblin Guru
What is the size of your heat exchanger?
I’m thinking about doing this, but will also have an oil cooler I want to run right next to it.
Here is a link to my install. It's 2.5x24.x7 from Frozenboost.

 

Desert Sasqwatch

Goblin Guru
They do sell the stock Bosch pump. But they also sell their "high volume" pump, which looks like the Bosch pump with their own turbine housing on it. It is supposed to pump an extra gallon a minute.
I've been watching this conversation and have some input that may help. First question, does your intercooler have air trapped in it? Without liquid in full contact with all the internal passages it will be far less efficient at pulling the heat from the intake air. The DF intercooler, at about 110 cu.in., should be big enough for 300HP, as long as the air is fully purged and the heat exchanger is working properly.
Next is the fluid pump. The Bosch pump is rated at 5GPM with zero pressure or 2.5GPM at nominal operating pressure and even less if there are coolant line restrictions. 2.5GPM should be adequate flow for the stock DF supplied intercooler and heat exchanger (based on the approximately 90 sq.in. front surface area of the core) as long as enough 'cold' air flows through the exchanger.
Air flow is key through the heat exchanger and is hampered by the stock mounting location, being exposed behind the radiator in the expelled hot air and lacking any 'directed' air flow as mounted. The air behind the radiator, with the open bottom and sides in the bodywork, is highly chaotic and it's possible a hot air eddy could form above the heat exchanger. The NACA ducts may help, but only if the air pressure coming into the ducts is higher than the air pressure under the heat exchanger - no air flow if the car isn't moving. Using the fan only will either pull air from under the car (ideal) or push already heated air from the radiator through the exchanger, depending upon how the fan is connected. This brings up the second question, is the fan pulling through the heat exchanger from the bottom of the car?
Using the fan - set up to push air through the heat exchanger from above - plus the NACA ducts into the heat exchanger with the stock parts is the best solution. No radiator hot air and the exchanger will see constant air flow. There are a few builders who have used this combination and may be able to provide more info how to set this up.
Some discussion has already touched on using a larger intercooler and having one with larger internal volume, in cubic inches, does two things for you. It slows the airflow down to exchange more heat into the internal fins and provides more thermal mass that takes longer to heat up. On the downside, it takes longer to cool down if the heat exchanger is not efficient enough or is undersized. A good way to know this to compare the cubic inch volume of your intercooler to the cubic volume of the heat exchanger. The closer to a one-to-one or bigger on the heat exchanger is adequate sizing.
Alternatively, a secondary heat exchanger, in addition to the stock DF exchanger, would be an ideal way to see if the intercooler is adequately sized for your turbo and HP. If by adding more heat exchanger volume the IATs go down you've solved your problem. If the temps don't reduce, it's likely a different intercooler may be needed - and you already have the heat exchanger cooling required for a larger intercooler.
This is my 2 cents on this problem.
 
Last edited:

Tim Moland

Well-Known Member
I've been watching this conversation and have some input that may help. First question, does your intercooler have air trapped in it? Without liquid in full contact with all the internal passages it will be far less efficient at pulling the heat from the intake air. The DF intercooler, at about 110 cu.in., should be big enough for 300HP, as long as the air is fully purged and the heat exchanger is working properly.
Next is the fluid pump. The Bosch pump is rated at 5GPM with zero pressure or 2.5GPM at nominal operating pressure and even less if there are coolant line restrictions. 2.5GPM should be adequate flow for the stock DF supplied intercooler and heat exchanger (based on the approximately 90 sq.in. front surface area of the core) as long as enough 'cold' air flows through the exchanger.
Air flow is key through the heat exchanger and is hampered by the stock mounting location, being exposed behind the radiator in the expelled hot air and lacking any 'directed' air flow as mounted. The air behind the radiator, with the open bottom and sides in the bodywork, is highly chaotic and it's possible a hot air eddy could form above the heat exchanger. The NACA ducts may help, but only if the air pressure coming into the ducts is higher than the air pressure under the heat exchanger - no air flow if the car isn't moving. Using the fan only will either pull air from under the car (ideal) or push already heated air from the radiator through the exchanger, depending upon how the fan is connected. This brings up the second question, is the fan pulling through the heat exchanger from the bottom of the car?
Using the fan - set up to push air through the heat exchanger from above - plus the NACA ducts into the heat exchanger with the stock parts is the best solution. No radiator hot air and the exchanger will see constant air flow. There are a few builders who have used this combination and may be able to provide more info how to set this up.
some discussion has already touched on using a larger intercooler and having one with larger internal volume, in cubic inches, does two things for you. It slows the airflow down to exchange more heat into the internal fins and provides more thermal mass that takes longer to heat up. On the downside, it takes longer to cool down if the heat exchanger is not efficient enough or is undersized. A good way to know this to compare the cubic inch volume of your intercooler to the cubic volume of the heat exchanger. The closer to a one-to-one or bigger on the heat exchanger is adequate sizing.
Alternatively, a secondary heat exchanger, in addition to the stock DF exchanger, would be an ideal way to see if the intercooler is adequately sized for your turbo and HP. If by adding more heat exchanger volume the IATs go down you've solved your problem. If the temps don't reduce, it's likely a different intercooler may be needed - and you already have the heat exchanger cooling required for a larger intercooler.
This is my 2 cents on this problem.
Thanks for the input. With the Z54 turbo, the h.p. of my car should be well over 300. I think that is where the problem lies. I purchase a type 10 intercooler from frozen boost. It has almost twice the volume as the DF supplied one. I also ordered another heat exchanger like the DF supplied one. I'm going to mount it in the back, under the coolant reservoir, with a fan on it, pulling in fresh air from outside. I will have twice the heat exchanger, and almost twice the intercooler. I'm also plumbing in a zzp intercooler fill reservoir which will help get out all the air. I plan on purchasing a coolant leak tester/vacuum filler from harbor freight to eliminate any air pockets when filling the system.
I found a thread on which circuit to wire the heat exchanger fan to, but it's in the BCM, up front. Is there anywhere to wire the fan in the fuse box area since my fan will be right below it?
 
Last edited:

Gtstorey

Well-Known Member
Thanks for the input. With the Z54 turbo, the h.p. of my car should be well over 300. I think that is where the problem lies. I purchase a type 10 intercooler from frozen boost. It has almost twice the volume as the DF supplied one. I also ordered another heat exchanger like the DF supplied one. I'm going to mount it in the back, under the coolant reservoir, with a fan on it, pulling in fresh air from outside. I will have twice the heat exchanger, and almost twice the intercooler. I'm also plumbing in a zzp intercooler fill reservoir which will help get out all the air. I plan on purchasing a coolant leak tester/vacuum filler from harbor freight to eliminate any air pockets when filling the system.
I found a thread on which circuit to wire the heat exchanger fan to, but it's in the BCM, up front. Is there anywhere to wire the fan in the fuse box area since my fan will be right below it?
With all of the additional piping, I would add an additional pump or upgrade the pump. One of the factors in an air/water heat exchanger is velocity of the fluid, the faster the better. I think you will likely be "off the pump curve" for the Bosch pump with the additions.

I would add a solenoid with a direct fused feed off the battery/starter wire and a trigger wire off of a "hot when on" circuit. Some of the fans have a solenoid built in or come with one. Although there is likely a switched circuit that was eliminated that was eliminated that would supply it directly.
 

OptimizePrime

Well-Known Member
Is there a reason you guys are fussing with the pumps, fans, electronics and all to stay with the w2a intercooler?

I get some don't like the aesthetics but it's much less of a hassle, cheaper, simpler design, lighter, more efficient to go with an air to air intercooler.

Edit: And yes using 91 gas is not helping you with the KR. LNF's are very sensitive to the octane levels - can you throw in some octane booster and see if you still have the same results? Have you boost leak tested?
 

Ross

Goblin Guru
I had to choose between the A2A and A2W too. I decided on A2W because the cooler is almost half the size, and easier to find a place to mount. The A2A is kind of like dragging a parachute with 50% wind blockage. You also can get some of the water weight up front, where it is needed. All at the cost of extra stuff, so you are right, A2A is simpler and lighter, but I understand both choices.
 

Tim Moland

Well-Known Member
Is there a reason you guys are fussing with the pumps, fans, electronics and all to stay with the w2a intercooler?

I get some don't like the aesthetics but it's much less of a hassle, cheaper, simpler design, lighter, more efficient to go with an air to air intercooler.

Edit: And yes using 91 gas is not helping you with the KR. LNF's are very sensitive to the octane levels - can you throw in some octane booster and see if you still have the same results? Have you boost leak tested?
I am using 91 octane because that is what I have readily available. Yes, I could do octane booster, or even purchase a drum of race gas. But, I'm going for convenience of being able to fill anywhere.
As far as air to air intercoolers go.... I'm assuming it would be mounted in the rear, or up high on the cage. Besides looking like an add on for an engineering mistake, the air does not flow well back there. On my car, I have a hood with a windshield. That makes air flow very stagnant. In fact, it tends to roll back to the cockpit from the back. That leaves you with the option to put fans on the A to A intercooler. At that point, it makes it just about as complicated as air to water, except it looks.. Let's say "funny".
I will look into boost leak testing. I'm not familiar with that. As far as A2A being more efficient... Everything I have read says a2w intercoolers are better at cooling intake Air.
 

Desert Sasqwatch

Goblin Guru
The only way the A2A intercooler is more efficient than a A2W is to have it mounted in undisturbed and coolest air available - at the front of the car. If it's mounted in the rear, as most Goblins have it set up, the chaotic and semi warm to hot air swirling around the engine bay does not lend to efficiency. Because of this, DF wisely chose the A2W intercooler system as it is as good as or better than the A2A given the design circumstances. Sticking with the A2A system is probably the best route to keep the efficiency and the asthetics of the car the same.
 

Tim Moland

Well-Known Member
If I were to know that this would be an issue, I would have used the mid frame rail (second from the bottom) as the intercooler pipes going to the front. Have some bungs welded into them at the front and the back to connect the heat exchanger to the intercooler. The larger diameter would give me more capacity. Being located out side should give it a little extra cooling capacity too.
 

Desert Sasqwatch

Goblin Guru
I believe the middle rail in the frame is not straight through like the bottom rail. The main rollbar hoop and the windshield/front dash hoop interrupt this frame rail.
 

Tim Moland

Well-Known Member
Well hell, let's calculate the intersections before welding and drill a 3/4" hole through them. We could fill the whole frame up! Some ideas suck. That was one of them.
 

Desert Sasqwatch

Goblin Guru
Sorry. Just didn't want you spend your time working on an idea that had an obstruction right from the start. BTW, I looked at doing that same thing a while back. Face-palm!
 

Brian74

Goblin Guru
I think your problem is the intercooler. I believe its only rated for around 350 hp and since you have the z54 I'm guessing you are right around that. I upgraded my heat exchanger to alot larger one with a fan and my iat2 usually runs about 15 degrees above ambient but sometimes up to 30 degrees above if I am driving it hard for awhile. I have the zfr 6758 so it's the same size turbo you are running. Frozen boost has a type 10 intercooler that is rated for up to 600hp. It's the same shape as the stock one only larger. I think that the one I will be switching to, looks like it will work with minimal modifications to mounting bracket. Here is my heat exchanger, I still need to add a side scoop like some others have done here but I am hoping that a larger intercooler will solve my issue View attachment 20619View attachment 20620
Justin, you are running the exact same Derale HE that I am and in the same location as well. What did you find for fittings? The thread size off the Derale is very uncommon and I had to fit some rather lengthy adapters ‘.
 
Top