I think the only way would be bonnet down with a fan right at the scoop, but we'll see. Matt will be doing open road tests, I believe. I'll try to get some dyno numbers as well, but they'll be comparison numbers only and not really show the true performance, I think.

 

LOL. Will, you done shared the secrets! .

By the way, intuition would have that there is probably EVEN MORE pressure drop when the IC is mounted in the engine bay, because the air moving underneath the car will create a vacuum-like situation which will pull more air back and down behind the IC as the speed climbs.... The pressure behind the IC may, therefore, be even lower [and the air even cooler] than your calculations would show.

 

yeh dyno runs won't do an IC justice....maybe you should recruit Matt to do his famous Thermal efficiency tests

 

The weatherman in me (I'm not "weather squid" for nuttin!) has go to ask;

If you cool the ambient air by my read, roughly 15 degrees, the moisture in the air condenses and either becomes cloulds (on microscopic nuclei) or condensed water that would have to come out of the IC at some place. Would the water get sucked into the engine?

I know that we're not talking about huge amounts of water, but hey, I'm not wanting to make rain in the engine bay!

Doug

 

Will, That is way cool although I got a little glossy eyed :-)

I'd be interested to see some 1/4 mile runs with temperature/pressures/mph data logged at both ends of the IC stock vs the new IC and the resultant mph at the 1/4.

I've done lots of dynoing and 1/4 miles and the math works out pretty good between mph/weight of the car/hp even if somebody is not that great at launching as long as your reasonably consistant the mph at the end will tell the story.

For a dyno/1/4 mile example if anyone is interested;

1/4mile calculator;
http://www.nationaldrivetrain.com/calcs/dragcalc.html

For the rx7 I plug in 2900lbs(me in the car)/360whp and I come up with about 117 trap which is about correct for my car. Now the 11.19 is a little optomistic maybe if I was on slicks, my clutch was slipping in 3rd so my time probably would have been around 11.6 or so i'm thinking instead of 12flat. But the time isn't nearly as good and indicator as the trap speed for hp.

The dyno is good but there are always heating issues becuase of lack of air flow across the IC. With the water injections setup on my rx7 I can do a bunch of back to back runs and maintain very consistant power readings. But that is not the case for IC cooled cars. I suspect the performance of the m7 IC will be tough to see on the dyno because of the lack of air flow.

 

Good thoughts, but given the internal geometry and how most airboxes are sealed, the water would get sucked down right around the header and get vaporized anyway. It would be difficult for the water droplets to get to the intake path, in my opinion. Even so, it's not enough to do anything but retard detonation a little bit anyway.

 

More coffee?

I've considered rigging up a blower to scoop interface with my local dyno to give me a more controlled IC blower. Might be worth it to set up some test runs.

I'll need to find a 1/4 mile track. We've got a bunch of 1/8 milers around, though.

 

Hi all, for those that are wondering. I use G-Tech runs and use 2nd gear for the HP runs. This gives me real world airflow. I look at ambient temp, pre-IC peak temp, and post IC peak temp, to get the IC thermal efficiency at redline, at about 70 MPH.
This is comined with no load pressure drops (pressure drop vs RPM) for the whole RPM range. Due to the behaviour of the differential pressure transducer, it doesn't work too well in the dynamics of the HP runs.
Last time, I did it with both 91 octane gas, and 100 octane. One gives benefits based on most driving situation, and has the dreaded timing retard in play. The 100 octane almost eliminates timing retard, and gives me HP benefits available with good gas, based on the tune maps in my car.

So, the power tests are done with real world air-flow.
Enough runs are done to get good statistics.
And pressure drops are found such that relative IC pressure performance can be measured.

The one drawback is the lack of pressure drop data at peak HP, this means that I can't do a pure air density comparison. To make up for this, I look at calculated fuel delivery from the ECU, to see if the ECU thinks there's more air there or not.

All in all, it works out pretty well.

Matt

 

OK PITA guy here again.
Those thermal plots are cool and all but I didn't see anything in them indicating the temperature of the little white rectangles.
There's nothing in there stating how much the air is heated while passing through the IC. You're demonstrating blowing air over an ambient surface or even more odd a surface that always manages to be the same temp as the air passing over it.

Now the fun part I see in this is:
If the exit air is moving 300MPH at a vehicle speed of 70MPH then if you can fast enough this happens under your hood


Fun facts page ->Cool sound barrier stuff here

 

Well, think about it a little differently. You have, by a very rough calculation, about 14 cubic feet of air flowing through the IC every second, at up to 300+ mph. It's going to carry the heat away in small bits, and it's unlikely that the temperature of the direct air is going to be affected that much vs. the volume, a few degrees, maybe 10 at most, before it's out of the intercooler. Cmpare this to the intake charge, which is flowing, by rough calculation, about 5 cubic feet of air per second at WOT at 5000 RPM. By volume the heat capacity of the cooling air is much greater than the heat being given up by the charge air.

It just doesn't stay in contact long enough to heat up, which is why the DFIC should be very efficient. The temperature of the intercooler surface should stay relatively close to the temperature of the air flowing through it, the ambient air whatever temperature that ends up being.

And I'll reiterate that these plots were meant to show general behavior of the design, not specific behavior of the intercooler. I admit, it's probably wrong, but maybe not that far off. We'll see soon, I hope.

Eventually you might end up with little pops under the hood, but I dunno.

 

That'd be cool. Better some darn blow off valve eh?

 

Word!

 

It is the rest of the world I was worried about... I guess the market really isn't big enough to worry about something like a south Korean knock off hitting the market

 

Even if it's not patented in another country and it's manufactured there, it can't be imported and sold here without considering to be infringing!

But WTF, it's a small market, so I don't know if anyone would really do it.

Matt

 

I should stick with chemistry... I know just ebnough about patent law to get myself in trouble

 

Has m7 given Dr. O the IC yet for testing??

 

We are expecting the first production run to come in next week. Depending on how serious the back order situation is will determine when the good Dr. will get his test piece. Our issue now is that some buyers are counting on them for the dragon. If we were making them with our own hands we would have more control over the delivery times. As it is we are at the constructors mercy. All i can say is we are closer than we were last week Thanks for the interest.

Randy
m7 Tuning

 

The M7 graphics are a go and we're leaving on April 30th so I hope you guys can manage to overnight it in time...if not, hope you guys can bring the parts to the Dragon for me...

 

I can vouch for that........

 

Well since I can't see the WMS there maybe you can bring this.
No fancy mirrors necessary.

 

I'm trying

 

Never, say never!

The way to keep people out is via proactive price management.

 

Just for this reason, I am bringing a dunk tank to the Dragon. I figure if you guys don't have an IC to play with, Randy will be more than glad to entertain us w/ the dunk Tank. Beats tar and feathers

 

DAMN , now i MAY have to pack a snorkle !

Randy
M7 tuning

 

The response has been incredible - with pre orders ! I thought the only interested parties would be those who orded IC units - BUT Alta purchasd several hundred tickets, Helix wants a bunch, ect.... WOW, I really underestimated the market.