I use the 997.2 ICs on the track for hard 20 minute sessions in a K24 600hp car and they are excellent at quick thermal recovery. Using data acquisition for timing and speed along various points on the track, my car is running just as strong at the beginning and end of a 20 min session in 100+ degree temps. Additionally they are feather light at around 7lbs each from what I recall. For street use, drag strip and stop light bragging rights you might be better off with a lower restriction higher flow core but for track work the 997.2s are great.

 

Looks like Markski is the direction im leaning.

With meth, I should be able to have a stronger, harder hitting car without going
bigger turbos etc.

 

You should consider that the concept is not only pushing air thru the side scoops. In fact the "footprint" of the side scoops in direction of the air flow is rather small, but it will always work as "air-catcher". I think Manthey had side scoops that stood further out to catch more air - I have no idea if that ever has been a proven concept or just a gadget.

In addition the rear bumper works like a venturi tube. The air passes the car on the sides and on the bottom at high speed and at the same time air is soaked thru the side scoops as well because of the low pressure area that gets compensated. It works like a straw with a small end on the scoops and a big end on the bottom and the IC is in between.

I would hesitate to go with water coolers as they will heat soak pretty much and you add weight to the car as well. That amount of water is better carried as water/meth mixture and your IATs will allways be low.

I will be spraying water/meth and I will be doing it pre-turbo because that's the maximum delta T I can work with and at the same time the better pressure ratio will make the turbo work more efficiently.

The spray will flow with the air into the turbo. After the ICs there will be another set of nozzles. This is for direct vaporization in the combustion chamber.

I my case this is for safety reasons as I don't have a built motor (and for the fun of it, I must admit). I do have Marks 4.5" intercoolers and they are as well a wonderfull piece of art and a high tech intercooler that works extremely well according to my data logging.

Just my thoughts. It will be interesting to see if your water cooling works for you.

Andreas

 

The water based coolers have already been proven in the 996TT. My IATs were 180*+ at the end of a Mile run where a similar car running the ice water were more than 100* cooler. That's good enough for me.

 

Huh? There are numerous logs showing otherwise with a marked decrease in IATs over 175mph with CTR, 997.2, Garrett and other coolers (seems to be a trend with the denser cores). You may be seeing the ramifications of too thick a core(?) and/or not enough density. Bell core?

In any case, A2W should do nicely for your setup and for a good price, but I dont agree that a proper high end AA cooler wont function above 150mph -that's when the really good ones start to shine!

 

This info came up in our research for my new mods. There have been wind tunnel tests that show the air flow completely missing the side inlets at speed. And by the way my IATs were documented to rise, I believe this without question.

 

This info came up in our research for my new mods. There have been wind tunnel tests that show the air flow completely missing the side inlets at speed. And by the way my IATs were documented to rise, I believe this without question.

And the reasons you listed below are the exact reasons why I am going with water.

 

Earl,

I'm just speaking from experience. My cores are not big by any means at 4.5". You can choose to believe otherwise. I have made dozens of high speed runs. And many over 200+mph, my traditional intercoolers simply so not cool intake temps at big speeds. This is why we tried a nitrous rail spray system that was not effective either. I even hit the spray at 180mph and let it spray for the rest of the run.

 

I totally believe you and your extensive experience & data at big mph -nice work at the mile! but I have a hunch its more an intercooler core capability issue than an air missing the coolers above 150mph problem. Are you running fenderwell intakes? Did the IAT slope change on the button? Maybe your particular setup and boost levels are beyond the capability of any 9x14" AA cooler, regardless of thickness.

 

I have this combo (Markski 4 1/2" with Aquamist 50/50 methanol) with K16 billets it works really nicely.

 

Thank you! I am not running fender well intakes and my filters are bolted directly to my turbos. The IATs didn't budge on the button unfortunately.

 

Todd, do you have an upper duct and lower duct with the 4.5 intercooler?

 

Ice water would cool things down but wouldn't it only be that cold for a very short time just after it is put in...

 

Only the lowers now that the rails are welded to the tops. But we sealed it off pretty well up top.

 

I don't claim to be an expert in fluid dynamics, but here's a thought. If the ducts have been removed, it may be causing some problems.

The upper and lower ducts serve as a conduit to promote the Venturi effect. The pressure outside the car directly in front of the side vent and the pressure of air behind the rear bumper serve to create a pressure differential in the long channel inside the fender (the narrow part of the upper ductwork.) This restrictive channel is should have lower pressure and higher velocity air used to cool the intercooler before the diameter expands once again through the lower duct and out the rear bumper.



This is from Christophorus (issue 300 specifically discussing wind tunnels and the 996.)



For your setup, at higher speeds, I have a feeling even nitrous cooling sprays won't help as there isn't enough flow because the Venturi channel/shape is gone.