Decreasing IAT on my Supercharged SOHC V6

I installed a Banshee M90 supercharger kit on my 2000 Explorer Sport with the 4.0L SOHC V6 engine.

The intake air temperature (IAT) climbed to 174 degrees during my last set of of pulls on the dyno.

As the IAT increases the PCM reduces spark advance to avoid detonation. Max power is reduced when the spark advance is less than optimum. The IAT is OK during normal driving and is excessive only during boost. There is an intercooler in the intake manifold between the output of the M90 blower and the head intake ports.

I installed a stock external ATF cooler on the driver side to act as a heat exchanger for the intercooler. Some airflow is blocked by hoses associated with my remote full flow and bypass oil filters, the passenger side external ATF cooler, and the thermostatically controlled engine oil cooler. Also, the lower part of the grille support blocks the lower two rows of the stacked plate cooler.

At first I thought the high IAT was due to the vehicle being stationary during dyno testing but during a short street pull a high IAT (164 deg F.) was also datalogged on a warm day driving at 50 mph.

There is about 1.5 inches between the back of the cooler and the front of the A/C condenser.

There is also room in front of the cooler if some of the hoses are relocated. I'm thinking about moving the cooler up and forward enough to place a puller fan between the cooler and the A/C condenser to increase airflow thru the cooler. My goal is to reduce the maximum IAT to about 150 degrees.

 

[boominXplorer]

Where is the air filter located? On my Diesel truck I cut a good slot in my header panel to help introduce ambient air in. Now while cruising I see exactly ambient IAT temps. It does start to rise to about 20* over if it sits for 3 minutes at a light. Then in the summer heat idling it has hit 150* but never really any higher.

 

[colintrax]

Since you're an electrical engineer I think this would be the best place to post

What about using one of these? http://en.wikipedia.org/wiki/Thermoelectric_cooling
The principal is pretty simple and could be implemented into any kind of design. Like an intercooler with the inside having fins on the cold side (inside)

 

[2000StreetRod]

air filter plans

Where is the air filter located? On my Diesel truck I cut a good slot in my header panel to help introduce ambient air in. Now while cruising I see exactly ambient IAT temps. It does start to rise to about 20* over if it sits for 3 minutes at a light. Then in the summer heat idling it has hit 150* but never really any higher.

Temporarily my air filter is where the stock air filter enclosure used to be.

I plan to fabricate a custom top for the stock enclosure and use one of my Amsoil high flow drop in filters. It will only pull air from the front via the stock cone and two 1 3/4" dia. flexible ducts.

I realize that currently I am drawing intake air from the engine compartment which is why when stopped on a hot day my IAT increases to 150 deg F. within a few minutes. However, at 20 mph or more the IAT rapidly drops to about 135 deg. F. I think pulling air from the front instead of the engine compartment will have less effect than increasing the cooling of the heat exchanger so it will have second priority.

 

[2000StreetRod]

thermoelectric cooler

Implementing a thermoelectric cooler would probably consume the surplus capacity of my 240 amp alternator. Actually, I think their application is limited to a fairly closed system like a freezer. One would be unsuitable where there is significant heat transfer due to airflow or coolant flow.

 

[colintrax]

Implementing a thermoelectric cooler would probably consume the surplus capacity of my 240 amp alternator. Actually, I think their application is limited to a fairly closed system like a freezer. One would be unsuitable where there is significant heat transfer due to airflow or coolant flow.

Yeah that makes sense. Well it was an idea

Your air filter location is hurting you.
Try to enclose it from the engine bay and let it breath from the front bumper. RAM air would be cool to. I've heard of people being able to significantly reduce vacuum with a ram set up. Of course you're boosted but it's still pulling vac before the super charger.

How many temp sensors are you checking? I'd be checking right after the air filter to see how hot the air is that you're pulling in. Good indicator to see if you're pulling in air from the engine bay.
My "ram" set up is ambient so long as I'm moving 20+mph. But it'll shoot up sitting at a red light. I let it pull from the engine bay incase water ends up higher than I expected

 

[2000StreetRod]

Ram air effect

My engine displacement is 245 cubic inches. At 85% volumetric efficiency and 3,000 rpm the engine is pulling (245*.85*3,000/2)=312,375 cu in/min
A 3 in dia intake tube has a cross section of 3.14*1.5*1.5=7.065 sq in
312,375/7.065=44,214 in/min air speed
(44,214*60)/(12*5280)=41.9 mile/hr air speed
So I would have to be driving faster than 42 mph to have any ram air effect.
At 6,000 rpm the airspeed would be 84 mph and at 1500 rpm the airspeed would be 21 mph.
I think the ram air effect is beneficial but much less than typically assumed.

I agree that pulling air from the engine compartment raises the IAT - especially if my Sport has been stopped for more than 4 minutes. Before adding the supercharger my IAT sensor was in the main intake tube just after the MAF sensor. I would log 150 degrees on a hot day when parked for more than 4 minutes. Using a remote reading thermometer I have confirmed that my radiator temperature on a hot day is typically 150 deg when parked with the engine running at idle and the hood open.

I agree that the main intake should have an inlet high above the ground. That's why I left the stock cone in place. It is protected some from splash by the headlight.

 

[colintrax]

I was saying that my ram air set up keeps my temps at ambient at speed because I don't have a true ram air. It's opened up a little in the engine bay incase the inlet is under water/mud. Don't wanna suck that up

How much it really helps with vacuum I'm not sure. Possibly none.

 

[rjcooperss396]

This might be a dumb question but where do you have the coolant tank for the intercooler and what pump are you using to circulate the water for it?

 

[2000StreetRod]

safe arrangement

That sounds like a safe arrangement. I've seen a video of an Explorer moving rapidly thru a large puddle to keep from getting stuck. Upon entering the puddle there was a large upward splash allowing water to enter the intake resulting in hydrolock and a bent connecting rod.

 

[2000StreetRod]

pump & tank

I installed a Bosch intercooler pump below and forward of the air filter enclosure base.

I couldn't find space for a tank so I modified the coolant reservoir to also serve as an intercooler tank.

 

[rjcooperss396]

Have you checked the flow of the coolant through the system? My buddy had the same issue with his Mustang. He was using a used Vortech aftercooler kit but with a GT500 heat exchanger and pump instead of the Vortech one that came with the kit. Our tuner (Steve Ridout of Powertrain Dynamics) pulled the return line from the coolant tank and had him turn the pump on. The water had a steady flow but not nearly where it should have been. It turned out that the used aftercooler had a bunch of crap in it that clogged it. He ended up buying another and that solved the issue.

 

[2000StreetRod]

coolant flow

I haven't measured the flow but I can see the coolant bubbling as it returns into the reservoir. The ATF cooler may be more restrictive than a typical intercooler heat exchanger and I'm using 1/2 inch i.d. hose for most of the runs which adds restriction. The Bosch pump flow decreases as the differential pressure (pressure due to restriction) increases.

I'm going to attempt to rig up a way to measure the pressure. According to the graph the pressure needs to be less than 6 psi.

 

[2000StreetRod]

air intake modifications

Since my ebay bargain heat exchanger fan won't arrive for a few days I decided to get started on the air intake modifications. First I modified the outlet of the silencer to direct the incoming air more upward and aft into the air filter enclosure.

Then I stuffed one end of a length of shop vac hose into the inlet of the silencer. I pushed the other end thru existing openings until it was downward and forward of the bulkhead so it would pull air from the front instead of the engine compartment.

Then I lowered the air filter enclosure base into position while fitting the silencer into it. Once the base was "locked" in position I inserted the ends of the other two shop vac hoses into it.

Now all air entering the base will come from the front of the vehicle.

 

[2000StreetRod]

ATF cooler as intercooler heat exchanger?

Any opinions on how appropriate it is to use an ATF or engine oil cooler as an intercooler heat exchanger?

I'm thinking about installing the largest heat exchanger that will fit in front of the A/C condenser on the driver side. I spent hours online looking at the size and port configuration of heater cores and couldn't find anything suitable. I searched for intercooler heat exchangers online and most are short and wide to fit across the lower front. I don't have room there because of my engine oil cooler & thermostat, remote full flow & bypass engine oil filters and remote ATF filter.

I found a B&M stacked plate oil cooler that is taller than my stock ATF cooler and may fit. Stacked plate coolers are efficient and are supposed to have less pressure drop than other types. However, the B&M cooler is advertised as being suitable for cooling various types of oil but there is no mention of water or engine coolant. SAE 10 engine oil at 20 deg C and I think Mercon V have viscosities greater than water so cooler flow restriction shouldn't be a problem. The viscosity of anti-freeze is greater than water but less than oil. The B&M cooler does not have the low temperature bypass that some oil coolers have which I think is an advantage in my application. It may be worth a try if it will fit.

 

[2000StreetRod]

Pressure test - stock ATF cooler

Using a T fitting, hose and clamps I connected my engine coolant pressure tester to the output of the intercooler pump. Then I connected my battery charger to the pump power connector.

The pressure gauge reading was 5.0 psi and the pump drew 2.1 amps. According to the previously posted graph my coolant flow should be 5.7 gpm. Based on that I think the problem is insufficient cooler size more than insufficient flow. My stock ATF cooler core is 10" wide x 7.5" high x 1.25" thick and has 3/8" dia. inlet & outlet ports. According to advertisements the core of B&M's 70266 oil cooler is 11" wide x 8" high x 1.5" thick and has 1/2" dia. female NPT ports. I found a used one for sale online and ordered it. Hopefully it will have better cooling and equal or less restriction. I'll pressure test it inline before reworking everything required to make it fit.

 

[2000StreetRod]

ACT spark retard

There are two PCM tables associated with spark retard for air charge temperature (ACT) which is equivalent to intake air temperature (IAT). The stock table is shown below.

To determine the impact the appropriate value in the first table is multiplied by the appropriate value in the second table. Past datalogs indicate that the PCM does not interpolate between ACT values. If the ACT value exceeds an entry in the table the PCM uses the next larger entry.
Using the stock 1st table at 171 degrees and 6100 rpm yields -100. Using the stock 2nd table at .79 load and 6100 rpm yields .0898. Calculating the ACT spark retard (-100 * .0898) equals -9.0 degrees. If the ACT is reduced to 149 degrees the spark retard will be (-64 * .0898) equals -5.7 degrees or an advance increase of 3.3 degrees.
The purpose of the above spark retard tables is to prevent detonation. In the stock configuration the IAT sensor was integrated with the MAF sensor and located a considerable distance from the head intake ports. In my M90 configuration the IAT sensor is located in the intake manifold between the blower outlet and the head intake ports. Even though my knock sensor is very active (which I'll deal with soon) I have heard no sounds of detonation and my spark plugs show no indications. Therefore I feel comfortable in making the ACT spark retard tables less conservative.

 

[2000StreetRod]

B&M 70266 oil cooler

The "used" B&M 70266 oil cooler I purchased from Amazon arrived today. It came in the original box with caps on the ports and had never been installed. One corner of the mounting plate was slightly bent so maybe it was returned for that reason. I hooked it up and ran a pressure test.

I only had some Pex 1/2 inch male NPT fittings with hose barbs on hand. The barb end is only slightly larger than a standard 3/8 inch fitting which adds a little restriction. I was pleased that the pressure was 5.05 psi and the pump current was 2.2 amps - just slightly more than the stock ATF cooler which is considerably smaller. The pressure may decrease slightly with standard 1/2 inch fittings. The B&M core is 8 3/8" tall x 11" wide and 1 1/2" thick and rated at 20,500 BTU. It will take a lot of rearranging to make the cooler fit.

 

[2000StreetRod]

Zirgo ZFB10 fan

The 10 inch fan I purchased on eBay for about $15 arrived today. It turned out to be a brand new Zirgo ZFB10.

Summit Racing rates it at 1149 cfm and drawing 7 amps. I'll probably wire it to only activate at WOT. It's 10 7/8" wide x 11 1/4" tall x 2 3/8" deep. I haven't tested it yet but it's supposed to be reversible (puller or pusher). I suspect it is very noisy. I plan to use it as a puller located behind the heat exchanger (cooler) and in front of the A/C condenser.

 

[Dono]

That rad looks like it would be an easy fit on the drivers side in front of the radiator on a stock truck. Am I wrong? I understand you probably already have added 'stuff' in that location, I'm just curious.