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Discussion Starter #1
Hi guys I'm finalizing the install of the water to air intercooler.
The pump that circulates the water where do you guys hook up power to?
Do you guys have it turn on under boost only?
Have it run all the time???

Need to finish this up ASAP so any answer to this question is appreciated ASAP.

Thank you
Luca.
 

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The intercooler pump should run all the time when the engine is running. Optimally, the power source would be directly from the battery via a relay which is triggered by the ignition. It's been so long since I've wired up mine, but from memory the cigarette lighter circuit is only powered up with the ignition ON, so that circuit can be used to trigger the relay. Don't forget to use fuses. I used an indicating fuseholder -- it lights up bright RED if the fuse blows. The following link is what mine looks like, but I got a 12V fuse holder and this one is for 32V (it might be real dim if the fuse blows, search via google to find the 12V part -- I guess Radio Shack no longer stocks it).

http://www.radioshack.com/product/index.jsp?productId=3087860&cid=ip:sem:rso:google:radio_shack_fuse_holder&stop_mobi=yes&utm_campaign=RSO_SRC_EN_NCA_TM_B_Hobby_Do_It_Yourself&utm_source=google&gclid=CJGrwdWp0cACFchgfgodrDQASg&utm_medium=ppc&gclsrc=aw.ds

Hope this helps...
 

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Discussion Starter #3
Thank you Gearhead!

My dad mentioned he wants it to come on with boost only.... Thoughts?
 

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You need to run the intercooler pump all the time. It can take several cycles for the water to completely dissapate the heat it absorbed from the turbo during boost -- depending you your setup, that could be 2 to 4 minutes. I use an intercooler radiator the same size as the engine's radiator with a 20GPM pump -- that runs all the time when the engine is running.
 

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You need to run the intercooler pump all the time. It can take several cycles for the water to completely dissapate the heat it absorbed from the turbo during boost -- depending you your setup, that could be 2 to 4 minutes. I use an intercooler radiator the same size as the engine's radiator with a 20GPM pump -- that runs all the time when the engine is running.
@20 GPM you are moving heated water to quickly thru the radiator (heat exchanger) not giving it a chance to due its job properly... Hence the larger heat exchanger is needed and that in turn chokes the air flow thru the engine radiator causing engine cooling temps to run higher...
Bell Intercoolers a major supplier of intercooler systems recommends a GPM of around 6-8 GPM... They also due a very nice job of selecting the right size intercooler and heat exchanger by having the customer fill out a detailed form about their engine and boost system...
 

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Discussion Starter #7
@BarneyO
Installed the Dayton pump that came with the SFR kit. With the supplied radiator.

Continuously running....
Also added water wetter to the water for better heat transfer.

It let's pretty cold :)
 

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on my old VR6 turbo set up I was running an AWIC. and I thought to myself, whats an easy way to have my pump run ONLY with the engine on... not key on, engine off as well.

Easy solution, use the alternator exciter wire as a trigger for your relayed pump.
 

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Barney, I've got no discernable change in engine running temps... If my IAT's are below 100F almost all of the time, that means the AWIC circuit is just above ambient. Spearco, Bell, etc., etc., have recommendations that are great for 90% of the AWIC applications. But, I NEED overkill -- that last 10%. The current Kalifornia heat-wave (100F ambient temps) is the reason... During these 100F heat waves my IATs can climb up to 118F. I'm still zipping around, merging into fast-moving commuter lanes from almost a dead stop. I can pull into a Burger King drive-thru and wait 10 minutes in the queue and then zip outta there like a jackrabbit. Through it all -- the IATs hardly budge. One of the keys to good driveability is to keep the IATs low. Yeah, for a 999cc engine the AWIC setup I've got is way overkill -- but it works in the baking SouthWest heat.
 

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Wow.. Gearhead, David.. nice to see your still here! Barney O, I saw the vid on your smart car with the supercharger! AWEEEESOME!!!!

So just to chime in.. did quite a lot of testing many years ago with single pass, double and triple pass radiator in my race car. The best cooling I got was getting rid of the double pass and making it a single pass radiator and moving as much water / coolant as I can. Since it's a constant amount of liquid, as long as you have the air flow and water flow, it will cool it down quicker than keeping the liquid in the radiator longer. And the restriction from the double and triple pass radiator didn't help with the flow but that's irrelevant here...

And as far as my own experience with the smart car's IAT... I have a 55 gpm pump running a 3/4 hose for mines haha.. yes it's overkill but it's definitely working well. xD if anything I need a larger water to air intercooler barrel but can't fit a larger one due to space issue.. ;( my heat exchanger up front is the same size but twice as thick than the engine radiator lol..

Barney, still impressed at your achievements, do you have the thread or a page handy where I can soak in all the goodies, read up and check out any pics of your hard work on that smart car that I saw on youtube? Someone had posted that video on my facebook wall and asked if it was my car haha, I said "no but I know who it belongs too!!!" haha.. congrats again.

Larry
 

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Discussion Starter #11
@Gearhead

Yep in AZ @100 degrees

IAT is at 118.
With the stock SFR setup I have.

Placed the Radiator up front of the car!!

Continuous flow with switched power from the cigaret lighter and battery. On it's own fuse.
 

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Howdy Luca!
Do you have an electric fan on the radiator? If so, are you powering it at the same time as the water pump?
I'm definitely going to have to change my intercooler. I have the SFR Stage 2 kit installed by Smart Madness, and the air-to-air intercooler aint cutting it in the Arizona summer. I'm getting intake air temperatures reported on my ScanGaugeII as high as 237°F with an outside air temp of 110°F. There just isn't enough air flow through the engine compartment to keep it cool. And with the air filter located where it is, it is just circulating hot air into the intake.
I like the mods that you had done to your H2O system (I saw it when we met in Scottsdale). With the changes you made in size of the intercooler, it allowed you to duct cooler outside air from the side scoop to blow onto the air filter. That in itself is a major improvement. And by relocating the air inlet & outlets on the intercooler, you've shortened the travel distance for the air through the intercooler to the throttle body. All good modifications in my opinion.
I'll PM you with my number.
 

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I don't understand why you go to such lengths to keep iat so low. In traffic on a 85 degree day last week, my iat was 160 on a na 999.

I know cooler is better, but it seems extreme. Is it reall so important to stay so low? I'm installing chibi's turbo setup next weekend, and I'm just worried that I should be doing methanol at the same time?
 

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Yes, it is EXTREMELY important to keep the intake air temperature as low as possible. Especially when boosting with a turbo or super charger.
First of all, hot air is less dense, less oxygen to burn per cubic foot of air. Performance suffers.
Second, really hot intake air can cause detonation which can lead to damaging pistons, rods, valves, etc.
Compressing air raises its temperature. Performance wise, the cooler the intake air temperature the better.
Well, until you start getting down to extremely low temperatures that is.
-200°F air temp might not be ideal either. :cool:
 

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Where, though, would you say I should be worried at 10 psi? 120? I get that keeping it near ambient to 100F is optimal, but where is it actually dangerous?
 
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