Air to water intercooler

[presslab]

I've completed my air to water intercooler install in my GL-10 wagon and EJ20G engine.  My desire for the upgrade from the WRX TMIC were for less heat soak and more consistent power in the summer.  I figured I'd document my results for anyone thinking of doing something similar.
 
Parts used:
Frozenboost type 14 intercooler
Frozenboost type 118 radiator
Jabsco 50840-0012 pump
GM Reservoir (pn 25884797) and 5 PSI cap (pn 15076936)
Generic Turbo XS type BOV
Fulree 12/24V IN 9V 5A OUT DC/DC converter

Metri-pack 280 waterproof connectors

From DiscountHydraulicHose.com:
4503-12-08 -- 3/4" Hose Barb x 1/2" NPTF 45° qty 2
4503-12-12 -- 3/4" Hose Barb x 3/4" NPTF 45° qty 1
4501-12-08 -- 3/4" Hose Barb x 1/2" NPTF 90° qty 1
5409-04 -- 1/4" NPTF Hex Socket Plug qty 1
4404-12-08 -- 3/4" Hose Barb x 1/2" NPTF qty 1
4404-12-12 -- 3/4" Hose Barb x 3/4" NPTF qty 1


This is what I received from Frozenboost:

 
I wanted to keep my AC condenser and trans cooler so that meant I needed to cut the bumper beam.  I tried to keep most of the material and I beefed it back up a bit by welding some metal alongside what was left.  Here's how much I cut out:


And here's the radiator mounted.  Half of the radiator is behind the bumper beam, with that small gap there for airflow.  I might cut more out after I get a feel for the how much heat the radiator can shed.  You can see here that to work with the cut the bumper beam I trimmed the plastic, re-used the metal strip, and redrilled the holes to mount the bumper skin.

 

The lower fitting was perfect at 45 degrees, but the upper fitting needed to be more like 70 degrees to pass through the existing hole in the body.  I cut and TIG welded the fitting and it didn't even leak. 

 

 

The pump is mounted in the passenger fender.  The brackets were welded to the bumper beam so no holes or welding on the body were necessary.  The outlet hose runs up and around the back of the headlight and down to the frame rail.  The flow routing could be hooked up a number of ways, but I decided I liked the Mercedes type routing the best.  Intercooler->Reservoir->Radiator->Pump

 

Here is the intercooler mounted.  I made a metal bracket that bolts to the spare tire hold-down nut and attaches to the back of the intercooler.  The bracket is flexible which allows the intercooler to move a bit as the engine twists.  Also there is a metal tab for the reservoir on the same bracket.

 

Now I'm getting some data from the system.  I've tested the pump at different voltages and measured the flow rate with a paddle wheel flow meter I got on eBay.  I tested it by filling up a 5 gallon bucket.  It's pretty big and doesn't seem to affect the flow rate.

 

At 12.8V the pump draws 6A and flows 5.0 GPM.  This is pretty good I think!  This pump is also smooth and silent.

At 8.5V the pump draws 3.2A and flows 3.1 GPM.

At 5V the pump draws 1.8A and flows 1.25 GPM.

 

My plan is to use the "5th injector" relay that the EJ20G ECU has which is unused to run the pump at full voltage when under heavy load.  When just cruising I will run the pump through a 9V regulator which will drop the power by half and increase the life of the pump.  I will be adding my own code to the EJ20G ECU to control this relay.  My algorithm thoughts are full speed for couple minutes at power on (for heat soak), full speed when above a certain load, and full speed for a couple minutes after load.

 

Results are great so far.  I've been able to increase timing by a few degrees, more boost, and most importantly more consistent power.  Heat soak is much better, although it could be improved.  Heat shields and a reservoir would work well; I think a pretty big reservoir could be made up to fit inside the fender.

 

I've now installed a couple thermocouples to log IAT2 and coolant temp and I'll post my results later.

 

 

 

[Nico]

dam good job you did 

[presslab]

Thanks a lot Nico, I've been enjoying your build.  I know you did AWIC for a while with a smaller setup and now are FMIC.

 

I have some information from my temperature logging.  The intercooler is more than sufficient, the highest temperature seen at the output is only 15 F above the water temperature, usually it's around 10 F.  That also means the coolant pump is working good.  Very pleased about that.

 

The recovery rate from the radiator seems good, but it's hard to tell as it's not summertime.  More testing is needed here.

 

I've been toying with the idea of a "killer chiller" clone.  This is where the air conditioning is tied into the AWIC coolant; people say it works awesome and can cool the AWIC to well below ambient.  There are some cheap heat exchangers at DudaDiesel, and now that I have a recovery machine I have all the equipment to do this.  Maybe the heat exchanger could be mounted in the spare tire well behind the intercooler, or if I make a good heat shield it can go above the turbo.  The original "killer chiller" puts the heat exchanger in series with the cabin evaporator so this compromises the cooling in the car.  My plan is run in parallel with a tee off the liquid line, a solenoid valve, and a separate TXV.  This way I can control my "killer chiller" with the ECU as well, so under highway driving I'm not wasting my A/C cooling down the radiator...

[Nico]

Thanks a lot Nico, I've been enjoying your build.  I know you did AWIC for a while with a smaller setup and now are FMIC.

 

I have some information from my temperature logging.  The intercooler is more than sufficient, the highest temperature seen at the output is only 15 F above the water temperature, usually it's around 10 F.  That also means the coolant pump is working good.  Very pleased about that.

 

The recovery rate from the radiator seems good, but it's hard to tell as it's not summertime.  More testing is needed here.

 

I've been toying with the idea of a "killer chiller" clone.  This is where the air conditioning is tied into the AWIC coolant; people say it works awesome and can cool the AWIC to well below ambient.  There are some cheap heat exchangers at DudaDiesel, and now that I have a recovery machine I have all the equipment to do this.  Maybe the heat exchanger could be mounted in the spare tire well behind the intercooler, or if I make a good heat shield it can go above the turbo.  The original "killer chiller" puts the heat exchanger in series with the cabin evaporator so this compromises the cooling in the car.  My plan is run in parallel with a tee off the liquid line, a solenoid valve, and a separate TXV.  This way I can control my "killer chiller" with the ECU as well, so under highway driving I'm not wasting my A/C cooling down the radiator...

 

 

the problem with my set up was I wanted more power and the air to air is just more efficient in the end... but for your set up it should work perfect for your needs.

 

 

where is your water box reservoir ?   if you add a water box you would be able to chill allot more.. I think your good just with that water box, thats a ej20g motor your using right ?

 

 

i was thinking of that a/c cooling thing and my good buddy told me not to do it.

[presslab]

My reservoir is small, just for expansion.  It's located next to the intercooler, you can see the pink coolant and the cap just to the upper left.  If I were to add a big reservoir it would be in the fender next to the pump, away from the engine heat.  But already the system is 3 liters coolant so it's not bad.

 

Yes the engine is EJ20G with TD05-16G turbo.

 

Do you know why your buddy said not to do the killer chiller?  It's a lot of extra piping, and I heard that it's bad for drag racing because of the water dripping on the track when running A/C.

[Nico]

My reservoir is small, just for expansion.  It's located next to the intercooler, you can see the pink coolant and the cap just to the upper left.  If I were to add a big reservoir it would be in the fender next to the pump, away from the engine heat.  But already the system is 3 liters coolant so it's not bad.

 

Yes the engine is EJ20G with TD05-16G turbo.

 

Do you know why your buddy said not to do the killer chiller?  It's a lot of extra piping, and I heard that it's bad for drag racing because of the water dripping on the track when running A/C.

 

 

 

If I remember right I was using like 10L of water, the extra water is in a waiting section to be cooled down, the more water the less heat soak and the less time to cool it...

 

my set up was running only on 70% or 80% throttle... 

 

 

I think if you just add the water tank for more water you would be perfect in the dead heat of summer.

 

 

the best person to talk to about this would be my buddy, he will steer you in the right direction. email him franz @ dieboldautosport . c o m

[EricS]

Great job! You could consider covering any portion of the intercooler that faces a hot (engine) surface with heat reflective foil tape, just be sure to get the good stuff (4-5% reflectance, not the cheap 50% reflective stuff that blingers use... Here's a silver one: coastfab.com/heat-reflective-tape.html). You might want to wrap the aluminum portions of your tubing with the same, otherwise they'll pick up a ton of heat. Also is that a atmospheric BOV? If so shouldn't you really be running a recirculating BPV?

 

Cheers!

[presslab]

Thanks!  I'll check out that heat tape.  My trans is out right now as I'm rebuilding it but it's almost done.  While I had the downpipe out I'm wrapping it too.

 

Yes it's just a cheap BOV, the sound does bother me.  I tried to hook it up to recirc but I couldn't get a hose routing I liked.  The engine management is an older JECS 4-plug ECU, so it doesn't care so much, and with an automatic I get WOT shifts so the BOV doesn't open.  I guess recirc would get me better mileage. 

 

I've done a couple other interesting additions to this, a "splitter" to help get the air flow up under the bumper beam and I also added some code to the ECU to change the AWIC pump from low to high speed depending on boost.  Actually once it goes to high speed it stays there for couple minutes.

[presslab]

Here's a photo of my "splitter", I think it helped, certainly not worse.  Also pictured is the resistor I used to drop the pump voltage down, it's for the DRL on a 2005 IS300 and it's about 1 ohm; this runs the pump at 9 volts most of the time.  And finally I attached the code that engages the "5th injector" relay to run the pump full speed when under boost.

 

 

 

PORT5		equ	$000D

ssmBoost        equ     $1341
counter         equ     $115D

highThresh      equ     $8F00   ; set to 0.8 bar, $C4
lowThresh       equ     $8F01   ; set to 0.5 bar, $AA
timeout         equ     $8F02   ; word, set to $5F28 (about 2 minutes)


	org	$C203		; replace purge sol code
	assume	m:1, x:0

        bbs     #1, $11C0, checkBoost  ; make sure engine running

	clb	#$80, PORT5	; set pump output off

        ldx     #0              ; clear counter
        stx     counter
        rts

checkBoost:
        ; check if boost above threshold
        lda     A, ssmBoost
	cmp	A, highThresh
	bcc	notAboveThresh

notBelowThresh:
        ldx     #0
        stx     counter         ; above threshold, so restart counter

notAboveThresh:
        ldx     counter
        cpx     timeout         ; timeout
	bcc	pumpActive	; branch if counter < timeout

	bbc	#$80, PORT5, end	; pump not on, so don't check

        ; check if boost below threshold
        lda     A, ssmBoost
	cmp	A, lowThresh
	bcs	notBelowThresh

	clb	#$80, PORT5	; set pump output off
	rts

pumpActive:
        inx                     ; increment counter
        stx     counter

	seb	#$80, PORT5	; set pump output on

end:
	rts