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Mag - what are ambient air temps in HK these days? What is the relative humidity?
 

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Mag - something is very wrong with your data. The intercooler (stock, rls, Lotus Cup, or other) most definitely delivers cooler air than that which it receives.

Are you huffing nitrous again?! :shrug: rotfl

My guess is that you have your channels reversed, or you don't have each of your thermocouples in the air stream.
 

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From what I've heard, direct water/meth injection isn't helping these cars much either -- the heat soak is just too much.
I'm seeing 20 degrees F or more drop in IAT temps w/ 50/50 injection.
 

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The PID called SAE.IAT *is* the temperature from the intercooler IAT sensor (the Bosch). 2007 Exige S.

Here is what happened when I unbolted the Bosch IAT sensor from the intercooler and assaulted it with a hairdryer.
 

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So...has anybody flowed the stock or rls intercooler at 28"?
I assume you mean 28" of mercury? About 14 psi? (Atmospheric pressure is about 14.7 psi at sea level.)

Wouldn't it make more sense to flow test the intercooler at 6 psig (about 20.7 psi), which is where it will be "working" while in service?

Any non biased parties have access to a flow bench? I'll provide one Lotus Exige S intercooler and one rls Intercooler (both to be returned) for testing.
 

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This graph (below) is non-scientific, but please see this thread for more details:

http://www.lotustalk.com/forums/f25/really-light-stuff-water-methanol-injection-55666/index2.html#post1085919

This graph compares the IATs for four 10 to 60 mph pulls (no injection) with four 10 to 60 mph pulls with injection, all 8 back to back. Top green line is IAT's for first four runs (no injection), lower green line is for last four runs with injection.

Injection occurs at two points. See thread (linked above) for details.

 

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I have already installed the Seine Systems water spray
A couple of notes re: spraying on to the intercooler (externally)... make sure to use distilled water so that you don't create deposits. Also, try a 50/50 mix of distilled water and methanol. The methanol will flash off easier than the water alone. This yields fantastic results. (See rls Injection thread).
 

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I agree. BTW, did you remove the upper duct from the clam to add the extra plumbing? That was seriously not fun.
I had the rear window out, so it wasn't that bad. Lots of ABS-plastic shards and dust, though.

It would have been nice if the duct were removable, and doesn't Lotus use the most tenacious urethane/epoxy ever invented?! :crazyeyes

P.S. Somewhere around here I have a photo looking into the duct from behind, similar view to your photo... but the two entry points are top, almost centered.
 

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Well, it took a while for me to find the mounting bracket for my flow meter, but I took a quick set of max and average flow readings for a short drive.

The max reading was 1100 fpm at about 80mph. Based on the calibration and data from this post: http://www.lotustalk.com/forums/f15...-air-flow-study-59117/index4.html#post1059881, that implies a flow of around 715 cfm. With just fettling and the Cup roof, only about 275 cfm flowed through the I/C. So if this data is accurate, I've increased the flow through my intercooler 2.6x, over a fettled clam with a Cup roof only.

That's very encouraging, but I'll need to run a full test, comparable to the original tests. Also, a took a quick infrared temp reading, after I'd shut the engine off. There was still a 20˚ difference across the I/C, even though no air had been flowing for at least a minute.

More to come...

:nanner: :clap: :bow:
 

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The guys in Australia are having good result with water mist sprays as well. This combination with a water mist would be very interesting to see.
Yes, I'm having great results with water/methanol injection combined with water/methanol (very light mist) sprayed externally on the intercooler. I have data logs posted elsewhere. http://www.lotustalk.com/forums/f25/really-light-stuff-water-methanol-injection-55666/index2.html#post1091074

I'm using 50% distilled water / 50% methanol by weight.
 

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Cool, that's great data!
While my setup pales in comparison to yours, I utilized a passenger to take readings while I carefully drove on private roads. ;)

Re: non-linearity, I'm not certain why. We took about [edit: 100] data points, but there was about a 5 - 10 mph variable wind..

I need to think about the implications for a while. I'm blown away that the mailslot was that much of a restriction... blown away. With the supplemental roof ducting, I expected only a 50% gain in airspeed through the intercooler.
 

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Yes, I think that the smallest cross section of the roof scoop flow path (in most cases, the mailslot) determines the flow through the ducting. When I opened the mailslot by 25%, I got a 25% increase in air flow.

Also, headwinds, tailwinds, and crosswinds add random noise to the data... that's why I used a square course to do my measurements, and then did a linear regression of the data to determine the most likely relationship between vehicle speed and I/C flow. I won't even get into the data integration and interpolation software that I had to write to put all the data together... :rolleyes:

Your data analysis is far better than mine, I just posted the raw data from a one hour drive at varying speeds. Luckily the wind was fairly low today. Each point in that graph is the average of about 10 data points. Excel drew its own lines. At some point I'll do the math and make a better graph.

Maybe the "octopuss" has merit!? Add both our systems together!
 

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How about combining Thomasio's roof duct bypass, apk919's side ducts, plus two pull and two push fans on the I/C and two inline blowers from the side-ducts.

I bet we can get 3000 cfm through that IC.... LOL

Every little bit helps... the thing is, with all of the ducts in the world, if you are sitting in traffic with no airflow your intercooler is heating up. Fans help there where no ducting can. Of course, the better the ducts flow, the faster you will cool your intercooler after you are stuck in traffic and get moving.
 
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