smokeshow

iTrader: (17)

Or the trusty CWA400 lol. Someone should try it.

Racer-X-

Be careful with the A/C compressor. You might consider some underdrive for the A/C Compressor pulleys and belt.

Time for an old racer's story. Back in the early 1990's, I was the crew/mechanic for a competitive SCCA Nationals showroom stock driver/car. That's when "showroom stock" cars had to run all OE parts from the parts department at the dealership, and there were virtually no allowed modifications from the way the car was delivered. I live in the Southeastern US, and we ran races all over the SCCA Southeast division. One particular national race was held in July at a very hot location. For the race, ambient air temps were in the mid 90's (F), and the humidity was around 90% as well. It was miserably hot. The driver went out and led the race, in the first 6 or 8 laps, he built up about a one minute lead over 2nd place. That's when he decided it would be more comfortable to turn on the AC. The car had AC (we ordered it that way to get the larger radiator), so we're stuck hauling around the extra weight (and parasitic load from the belt/pulleys) of the compressor, plus the weight of the rest of the system. Driver was thinking, "what am I hauling all this around for. I'm leading by a long way, and it's hot as hell, I might as well use this air conditioner." After about a lap, there's a minor "explosion" under the hood, and smokey/vapory stuff is pouring out from under the hood at the end of the longest straight. Driver pulls into the pit the next time by, and it's still smoking/releasing vapors from under the hood. I jump over the wall and open the hood, expecting that I might find "game over" in the form of a broken coolant hose or some kind of oil leak or even major engine failure. Instead, I see refrigerant and oil being spewed from the broken pressure hose between the compressor and the condenser. I yell at the driver over the radiator, "Turn off the &$#**# Air Conditioning and get back out there." He came back out about 10 seconds behind the new leader (2nd place before the incident) and he did manage to run the guy down and pass him.

The moral of the story here is that A/C systems aren't designed to run at maximum RPMs for extended times. You may find the weak hose or line in the system if you run the compressor at full engine revs. And that's really when you need the cooling capacity the most from the intercooler system.

BTW, for an ice/water based cooling system, if you run antifreeze (good to 0°F) in the loop through the ice chest, you can salt the ice and the ice/water in the ice chest will get down to 0°F. That's actually how 0°F was discovered and defined. That's the coldest you can get liquid water in a brine solution with common salt (NaCl).

smokeshow

iTrader: (17)

I don't believe anyone who manufactures these things recommends changing the WOT AC clutch disable settings...for exactly the reasons you just mentioned. Once you get into that WOT/high RPM area and the compressor kicks off, you're just down to the leftover cold water. I don't think the physics would be in your favor otherwise anyway...6500rpm with the compressor pulling some obscene amount of torque from the crankshaft is gonna cost more power than the cold air gives back. So its always in your best interest to kick the AC off right where the OEMs decided it should.

LSswap

I don't think anyone is considering running the compressor the entire run. It's just a question of how much cooled fluid needs to be in the reservoir to sustain acceptable charge temps during a run.

Anyone logging their charge temps, let us know how they held up and how much coolant you're storing.

jordoza

I never meant to mislead anyone into thinking I was ever going to run an ac compressor at full throttle or max rpm. I've been a tech for 28 years. I know a variable displacement ac compressor might be able to do it but why when the water in the intercooler tank is really what cools the charge. If you've never watched how a killer chiller or set up like it works go to there site. Watch the videos. It will explain a ton. None if them run the ac compressor at max rpm or even during a run.

Racer-X-

@LSswap ,

A couple questions. What track are you running this on? Is this a drag strip? Or a road course? Or are we talking about autocross runs?

How long is a run? I'm looking for both distance and time for a run.

randeez

it easier to "maintain" cold than it is to ask for it instantly. always having the intercooler brick cooled is much more efficient than having 90* intake air and 90* intercooler brick, going WOT and then flooding the brick with cooled water. the hot air is going to win. these chiller kits use an expansion valve, once the fluid is cold the demand for refrigerant drops and valve closes. youd be better off targeting a certain air temp and letting the pwm ramp up or down the coolant flow to meet it.

chiller doesnt do any better of a job than icing the tank for a 1/4 mile run, if your intake temps jump up 50* on a pull then its going to do the same exact thing with the chiller - given the storage, pump, etc are all the same. mine could be a whole lot better set up, but form was more important than fuction.

this is shearer fab A2W hi ram intercooler, 10gal reservoir, cwa400 (on manual pwm controller), about 25' of 16an hoses front to back, not sure which turbo but old log -cleanest one i could find. probably older 92/110 turbo. with this set up, the IATs are about 20* higher than the chiller coolant temp. ex- IAT of 59*, chiller temp is around 40*

a clip of a log on mine, all pulls done in a 3 minute window, light blue top row is intake temp ....
temp start at 59*>104* 35-125mph ,
next pull 68*>122* 80-135
next 81*>122*, 80-125
84*>111* 78-115
then (not shown) takes a little less than 5 minutes to get intake temps back down to about 60*

gsteele

If this is an idiotic question then please be gentle. Is there a difference in temp between the air going into the cylinders that are closest to the incoming water as opposed to the water outlet on the intercooler brick? I am assuming the water flows one direction ie front to back (or vice versa) so would the air going into the back cylinders be warmer?

LSswap

1/4 mile Drag strip, 10 seconds or less.



I'm surprised that got heat soaked so fast. Thanks for the logs.

Still 59 to 104 is better than 80 to 160.

randeez

the way this turbo is set up, its closed off in the engine bay sucking 120* air into the compressor right off the radiator. without the chiller running thats about where the IAT sits.
not exactly heat soaked.....this is also the effect of the coolant on the IAT, thats why i mentioned the coolant is usually about 20* cooler than the IAT, so when you see an 80* IAT...coolant temp is still in the 60s. its just that the air into the compressor is already so high

2JZFC

iTrader: (26)

Did no one see this comment? No doubt the solutions being discussed are going to reduce the IAT, but will there be reasonable net gains if it requires adding ~160lbs of weight, not to mention the complexity? Remember, that much added weight will affect initial acceleration and possible affect traction, depending on where you it. Unless I missed it, you didn't say what size engine and turbo. Dealing with a similar issue with a 370 I am tuning. Couple of nights ago it had 104* at the launch and 179* through the traps with ambient of around low-70s and E85. We're dealing with T4 turbo and trying to squeeze 1000rwhp out of it. Car has gone much quicker before so we're going to put back on the alky inj with 2 15gph nozzles until we can upgrade. If the turbo hot side is too small for the engine displacement, that's where most of the heat is coming from.

If your ECU can control the alky injection, you might consider picking up the needed components and giving that a shot first.

jordoza

I actually did see this post and answered it by saying I'm mounting my tank just behind the rear axle so it should help my traction. I'm not a fan of the weight but I like driving my stuff alot and having run meth injection the tank goes empty and has to be refilled. It becomes a bother for a vehicle you drive not just race.

Jwooky

I agree this is a Rube Goldberg solution for a drag car. Ice chest would be just if not more effective.

Maybe for a track or street terror.

ramairetransam

iTrader: (18)

i didnt read every post but why dont you run meth injection . is your blow off valve before the intercooler. I have a procharged car and my red race valve is before the ic , so its not heating up the ic as much as it would if it after the ic or right before the tb like a of of people like to do .

2JZFC

iTrader: (26)

Sorry, missed your reply. However, I have to roll my eyes at folks who say they don't use meth injection because the tank could go empty. Like gasoline, ice for A/W I/C, nitrous, etc, the tank tends to go empty when you use it up Sorry, excuse the sarcasm.

LSswap

I saw your comment. I agree with some parts of it and don't agree with others. First of all, I don't agree that you'll be adding 160 lbs. This will replace my fairly heavy 4" intercooler and 2 fans. 5 gallons of fluid weights 35 lbs. E85 is not available around here and remember that this for a cruiser, not an all out drag car.

You have to admit that a colder charge is denser and you will be able to get more charge into your cylinders and less risk of detonation. Adding alchohol/water displaces some of the air you can fit through the system. I believe the colder, denser charge will more than make up for added weight by adding more charge into the engine and reduce detonation. A cooler charge does not have to exclude alky injection. If you want alky, you can add that as well as a cooler charge.

I've run alky as far back as 2003 so that's not a problem for me. I would only run alky if it was direct into each port, so there is complexity in that installation. If I wanted to get every bit of power out of my engine, I would run both, but my goal is just a little safer operation and modest power gains. Cooler charge and alky are not mutually exclusive.

jordoza

I get it and like I said I used meth injection before in fact I was running a pro meth turbo compressor nozzles and a charge pipe kit. It worked but it was just a Hassel and I never saw the results I did from just a good water to air set up. I always seemed to make less power. Maybe I was just to afraid to run it on the ragged edge but I can read plugs pretty damn well and the meth set up never seemed to work as well. I wanna run around iced constantly but that would be a ton of work for a car I drive regularly or will again when I finally get it done. And no the water to air set up isn't the hold up it's body shop jail. (I truly think a body shop is outside of the space time continuum resulting in 60 days actually being 2 years in real time. Lol. Anyway. ) this home made killer chiller is the next best thing in my opinion. I already have the ac system on the car and I only have to tap in to it to make it work. Plus the way I'm doing it if I decide to ice the tank I still can.

Kfxguy

iTrader: (1)

You do realize that the compressor kicks off at wot? It also will kick off past a certain rpm and head pressure.

LLLosingit

iTrader: (4)

Yes and ice doesn't so it's not only lighter it doesn't consume power during any part of the run, I have an LSA setup and looked into it quite a bit, For the street it makes sense because you can drive around with a nice cool vehicle (inside) on a hot day and switch it off to make a quick hit. At the track ice makes more sense to me, With AC You'll get one good run and the water won't be cool any longer and you'll have to leave the car running for an extended time to cool the water off for a second run. Ice doesn't need long to cool and the engine doesn't have to get heat soaked between runs.

Kfxguy

iTrader: (1)

what if you dont have ice? What if you get to the track and you forgot to pick some up? What if the track is out? What if you wanna race someone in Mexico? Do you tell them to pull over at the gas station so you can get some ice? I have this odd feeling about doing things that are extra steps or extra trouble. If you already have ac on the car, an inter chiller adds how much weight? 30lbs? 50lbs? But you have it ALL THE TIME. the ac doesn’t kill but maybe 5hp down low. As soon as your foot is to the floor, basically the ac cuts off. You lose nothing. If you have a 13 second or 14 second car, you might see a negative difference, but I doubt because it kicks the clutch off past like 3500rpm, and or full throttle. If I had the $$, interchiller is what I’d do. Adding ice to make runs sounds cheesy to me. I laughed at people that used to ice their intake. That’s just silly to me.