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Want to be clear here, talking about EXTERNAL spray not internal.
 

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Guess I need to start data logging my results. Unfortunately I can't find a pump capable of efficient misting that is 12V DC that doesn't draw excessive amps. The 40-70psi pumps I've used really just don't mist regardless of the nozzle.
 

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Chris, WOW -- you da Man! Just order unit, overnight.

That does look like a viable unit!! Guess I missed your post, sorry.
 

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Kit is missing one part, but I think I can work around it as I have a boost/relay trigger. Part is on back order (pressure solenoid that runs inline with the hose).
 

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Misting is based on the theory of Evaporative Cooling (or Desert Cooling), which uses the scientific principal of Thermal Dynamics, which states that water requires energy to evaporate, or 600 calories of heat per gram of water, and this heat is taken from the environment.To achieve this water is forced through a very small orifice creating a very fine mist or fog of ultra fine 50 micron water droplets (smaller than the diameter of human hair). Once these very fine droplets of water are exposed to the hot atmosphere, they quickly absorb the heat present in the environment and evaporate in the process. This quick heat exchange is known as Flash Evaporation, it takes heat from the surrounding area, and drops its temperature by up to 35 degrees F, and consequently the air is cooled.

High Pressure misting generates Fog, which is ideal misting, with finest mist. However the cost is way high too, because it uses high pressure pumps, and stainless steel tubing, and metal fittings to handle the high pressure. The finer the mist, the more efficient is the system (due to the larger surface are), and the higher the pressure the finer is the mist produced.
I think the issue I have with misting directly ON the IC rather then trying to cool the air flowing over the IC is that air flows thru an IC more evenly, mist will not. A mist will most likely just contact a smaller surface area so you end up cooling only a small section of the IC. Cooler air will flow better and provide a more uniformed coverage.

But want to be clear, water spray vs. water mist -- with water spray you will go thru water at a very rapid pace for track duty and you'll have a bunch of wasted water that drips on the engine or in my case tires.

Anyway, I think best way to settle this debate is to do some testing -- and that's exactly what I plan to do an submit my findings to you folks. But in all cases, I'm only hoping try and keep IAT at sane levels, not really expecting massive reduction in IAT or big HP gains (just try to minimize).

Kit arrives tomorrow, hope I have time to install before event. I'll check IAT after each track session.
 

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Just got signed off on my LogBook, so apparently it's not an issue.

dmh, you can apply your logic to any fluid used by the car, oil, radiator fluid, gas, water injection, etc. etc. -- a failure is a failure -- just ask FF about the car that dumped oil on the track during cool down and they hit the oil and car went off. But out of all those fluids, water is the most evaporative and least slick.

Also, some professional race series use water injection on the brakes. If it's working right it's not a problem, just like any part of the car. In my case, it wasn't working right.

QBall, went thru that article, apparently that kit would work only for max 9 seconds before the pump would overheat and fail or need a long cool down period.
 

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dmh, what is your issue dude? It passed tech and I just got my log book signed off (yes one that is accepted by SCCA). You didn't answer my question, how is it any more a safety issue than any other failure in a car??

Like any system, if it is done right, it's not a safety issue. So what's next, prevent the use of synthetic oils because they don't dissipate and absorb as well as standard oils?
 

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You can play the "what if" game til nobody shows up to a race -- is that what you want?

Which is more dangerous a failure in a poorly installed Accusump that dumbs oil on the track, or a failure in water spray system that dumps water on the track?

If I were to follow your logic of making everything a safety issue, then we really should NOT be racing period. If these are the LCS rules for racing, then count me out.

This sounds more like an issue of not wanting to deal with such a system so lets ban it. Or worse yet, someone (aka a series sponsor) is selling a "more safe" approach to reducing IAT but it'll cost you $4000 vs. $400. Cause then we get a new sponsor who can sell there $4000 system.

I know the deal, this is not new news to me, if that's how you want to play, then go for it.

P.S. For the record, my original Water spray system that failed was installed by an LCS Series sponsor, you got issues, then take it to them.
 

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Where did you get the fans from?

I plan to get the RLS next week (if I can find some money), and when I get my motor back together I have already installed the Seine Systems water spray -- with the fans as pullers, I think this could be a great when combined with water mist to cool down the IC at lower speeds.

FYI on my Seine Systems mister, the motor for it pressurizes a small tank and pretty much runs continuously keep high pressure in the tank. A solenoid then opens/closes to release water at high pressure -- solenoid is trigger by boost but can also be swithed on/off in car.

I realize we're not looking a huge improvements, but even the small ones are significant.

I've opened up the mail slot already -- hmmm...think I need to get some data logging done once I've got my car back together.
 

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Thanks for the response, could I get specific model numbers?

Will try water/meth mix (external).

Do you happen to know the AMP rating (for fuse) and/or load these draw?

Thanks, Rob.
 

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When sitting in my garage making tuning adjustments (10-15 minutes at idle and/or some rpm hits) charge temps goes up to about 121 F. Same thing happens when driving in LA traffic -- goes up to 121.

It seems to cool down extremely rapidly with higher speeds. Going over the grape vine, I was trying to generate some heat going up with no success. In fact, in 6th gear over 100 mph I think I may have to make a tune adjustment as it really keeps the charge temps very low. At larger tracks like Thunderhill 3.19 mi long straight where one hits 130-135 or so or like Fontana 150-160 or so I don't think heat soak could ever become an issue (at least with the RLS anyway).

Probably end up tuning for each track I go to next year.

Rob.
 

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It was a little more than just a freeway pull 1 hour of stop and go LA freeway followed by a long long long pull up the grape vine at WOT -- I'm sure you've gone up the grape vine (it's not a short quick hill). But if you take a look at percent of track time actually on throttle it's not as massively different. But I agree you're not creating tranny heat, brake heat, etc. etc. -- tracks are different and my point was each track will be different.

If I had hit 150 at Fontana in a Mustang Cobra with worse aero and worse HP/Weight then I'd expect to at least do the same in my Lotus (I hope).

Rob.
 

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1999 Mustang Cobra is a moving brick, it'll never be as efficient as anything Lotus. At the time the Cobra was running around 331 wHP but did have a good track gearing. But totally agree, need to get it out on the track and see.

But so far the following appears to help considerably with engine bay temps and air charge temps:

1. Opened mail slot
2. Sealed IC Shroud
3. RLS IC
4. Bumper removal with VonHep
5. Heat wrap exhaust pipe from header to muffler

For track I plan to drop in a ceramic coated no-Cat pipe.
 

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I don't understand how the side scoop flow is not just going to collide with the roof flow? What is stopping the side scoop air pressure from going out the roof and/or the roof air from going out the side scoops? Both will be paths of least resistance vs. flowing thru the IC itself which has a very high resistance to flow?

To make your side scoop design work efficiently, you'd need a three chamber (isolated) IC shroud (think exhaust headers). What you've done here is most likely got side scoop air flow with higher volume pushing air out the roof scoop (some will go thru the IC, but it might be worse than what the roof scoop alone could do).

I think your design would work MUCH better if you ran the side scoop ducting directly into the IC shroud with 3 isolated chambers in the shroud - left chamber for left side scoop, center chamber for roof scoop, and right chamber for right side scoop. Isolate the chambers on the IC surface using rubber/foam molding (you would need to figure out how to mold plastic for each internal shroud chamber). This way, the only path for the air to flow in all 3 cases is thru the IC regardless in the differences of pressures between all 3 paths of air flow.

Not trying to knock your design because heat soak is a problem and the more air one can flow over the IC the better. I think you're on the right track, just needs some refinement.

Rob.
 

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Sorry if this has been asked before, but what are you using to measure air flow across the IC fins and out the other side? From your CFM data is does indeed look like the IC is the path of least resistance.

I still feel the flow dynamics are more efficient when unequal air pressures are not colliding with each other. Unless you have a perfect direct head wind, all air pressures from all 3 entry points will never be the same.

But it sounds like you'll be gathering Air Charge Temps this Tuesday from a track day? I'll certainly be interest to see those air charge temps. But the bigger question is, will this do anything to improve engine performance (and lap times) thru a session or will you be fighting increased drag.

I hope I'm not sending the wrong signals, I'm glad your doing this -- my questioning is purely from a scientific aspect. That's what science is about, always under scrutiny (question everything) and that's what makes it work. So please don't take my comments in the wrong way.

Rob.
 

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Excellent, looking forward to your data. :up:

Rob.
 

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Andy,

Did you collect "baseline" data before any changes to the roof and side scoops?

Also interested in exactly how you "taped" the side scoops off.

Specific data I would like to see is (if you have it):

1. Side scoops functioning as normal stock side scopes (only larger) with stock roof IC duct and your inlet wholes taped off from inside the IC duct.
2. Side scoops routed to roof IC duct (open).
3. Baseline with stock side scoops and unmodified roof IC duct.

Ambients temps provided in all cases. Also, are you running the stock IC? And do you have rear bumper removed? Cat or no cat? How much boost were you running?


Rob
 
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