Would having an intercooler between the carb and manifold in a naturally aspirated engine provide some sort of gains? Can anyone help me with the pro's and con's of this type of setup. I've never seen a setup like this and haven't heard anything on whether it's more trouble than it's worth (thus, no need for anyone to ever do this), merely a novelty (like running dual 650's on a factory/mild small block) or is it something only forced induction setups can really benefit from? Any input is greatly appreciated
A cool can would be of benifit with a naturaly aspirated engine. it is before the carb and cools the fuel. Or cold air induction like in iar from someplace other than under your hood. On a naturaly aspirated engine the incomming charge doesn't get heating like on one that is huffed. I have seen pro stocker ice down the intake between rounds but their world is measured in thousandths of a second.
It won't work on a naturally aspirated motor. When you put the intercooler under the carb it takes pressure to force the mixture through the intercooler, a Supercharger or a Turbo does this, but o a naturally aspirated motor all you will do is lose velocity of the incoming charge and therefore loose power.
I figured if there was another cheap bolt-on way to gain power, people would be interested. I have a rough prototype of a carb mounted intercooler I built years ago as a project for about $20 without much thought on application and just how (in)effecient it might be, but it seemed like a good idea, even if it only adds 5 - 10hp (or merely makes the engine run slightly cooler), that's 5+ bolt on horsepower. I recently decided to maybe expand on the prototype and build one for my 327 fuelie.
An air gap manifold helps things from getting hotter and provides some performance gain over a superheated manifold. An intercooler theoreticly should provide some gain, about as much as a cold air intake and certainly more than the "tornado" .
How do you keep the fuel properly atomized as you're cooling it? While you don't want it to get hotter (one of the benefits of "air gap" style manifolds), you probably don't want to cool the charge after you've sprayed the air/fuel mixture into it, as the fuel droplets would coalesce as the air mixture condensed. And, as hotroddon suggests, you're going to lose air charge velocity as well. Cool the air before it goes into the carburetor for best results.
Theoretically, if the charge was chilled enough, could that offset the possible losses from obstructed air flow and coalesce? The homemade 4-71 intercooler on my '35 certainly makes a big difference when running just water through it, but toss some ice in the chill box (I don't know the specific name for these) and the engine becomes a whole 'nother beast. I would think that this could be worked into a bolt-on design, rather than the major modifications needed for most pre-intake intercoolers or the high cost of blower intercoolers.
A water and alcohol injection kit will help cool the intake charge. Kits are available aftermarket or build your own.
Yeah, I have done some work with water, alcohol, windshield wiper fluid, propane, and a few others. Thank you, but I'm talking about an actual bolt on intercooler rather than injecting anything extra. I figure a typical manifold mounted intercooler would be too restrictive in a n/a application, couldn't this be overcome with a less restrictive intercooler? More spacing between cooling fins and a taller profile? Thank you for the input so far everyone. I know it's all theoretical, but you've given me much to think about
Why not just bolt one on and see that those fellas that have answered your question already are wrong or not. You are going to lose more than you gain unless you figure out a way to keep your plenum full. Maybe you can use it at high speed with ram air effect type of a scoop.
Intercoolers are necessary because with superchargers and turbochargers the action of compressing the air causes its temperature to rise. The result is a "hot charge" feeding the engine which is not good because hot air is less dense than cold air. The intercooler only counteracts that temperature rise and nothing more. With normal aspiration, you have no temperature rise, in fact the opposite occurs. The venturi action causes the charge to cool--- so much so that sometimes carburetors freeze from it. Put your hand on the carb of a running engine and see how cold it gets. Carbs can freeze on a 60 degree day if conditions are right. Sometimes carb bodies get hot from the engine heat, which is why carb spacers are usually plastic or phenolic or wood. They act as a thermal break to prevent engine heat from climbing up to the carb. The other problem is that placing a device in the path of the flow will change or impede the flow characteristics. Not a good thing. So, no, an intercooler placed in the intake path will not help anything.
Ed Hamburger built an intake with plexiglass enclosing the runners, and used to fill it with dry ice and alcohol, said it was worth better than a tenth. I used to race in a heads-up, small tire class. Some guys (nudge, nudge, wink, wink) spray the intake manifold down with brake-klean while they are in the staging lanes. The low latent heat of evaporation really sucks the heat out of the casting. Theres an old saying. Feet in the furnace, head in the icebox.
As Don has said, anything that interferes with the incoming charge is going to cost more power than you are going to gain by cooling the incoming charge. Cooing the incoming charge IS worth power, but you have to look at other ways to do it.
Cooling the intake charge would be worth something, but the question is, "What are you going to cool it with?" Intercoolers work nicely on turbocharged and supercharged cars because the compressed air gets much hotter than the ambient temperature of the air around the car. That means the ambient air can be used as a heat sink. The rate of heat transfer is proportional to the difference in temperature between the two substances on either side of the heat exchanger. In the case of a naturally aspirated vehicle, the intake air never gets much hotter than the ambient air, and that means that an intercooler won't be able to pull much heat out of it. In order to get anything useful out of the intercooler, you would need a cold can or ice tank. That would allow you to set up a pretty good temperature differential between the intake air and the cooling medium (ice water). Ford showed a variation of this idea on the concept for the later F-150 Lightning trucks. The AC system could be used to chill the coolant in the air-water intercooler, which would make the system much more efficient at removing heat. Of course, the system would cost horsepower and fuel efficiency when in use. Water and methanol injection offer another way to cool the intake charge. However, they make use of latent heat of vaporization to take heat out of the intake air. The cooling medium's state change from liquid to vapor does most of the work. Even so, this would have a greater effect in really hot air than in relatively cool air. Because of the packaging and air flow considerations you have listed, I think the closest thing to what you are looking for would be a variation of the Ford Supercooler concept. You would need to install a small AC evaporator inside your intake. If you already have AC, that could be pretty stealthy. However, as other posters noted, you might cause new problems by condensing the fuel right out of the intake charge. Not good.
It doesnt? What do you consider "much"? Would you consider, say for example, a 120% increase over ambient to be "much"?
inject water?cool the inlet air before enters carbs/&use cool can for the fuel think systems to cool inlet air has been used at bonniville? one of the side benefits of nitrous is that it cools the intake air &fuel also prevents detonation.........
Relatively speaking, no. Bear in mind that the Fahreheit scale starts at about 255 degrees Kelvin, so our air is pretty hot when compared to "absolute zero." So air at 65 degrees F is at 291 degrees Kelvin. If you take air at 65 degrees F and heat it to 143 F, that appears to be a 120% increase in temperature, but it's actually only going up to 335 degrees Kelvin. That's an increase of only 15%. Blower exit temperatures can easily get into the 300s Fahrenheit. That would be an increase of 45% total heat. That is, relatively speaking, a lot.
Well, it may not be "much" in your opinion, but I can tell you from back to back track testing, that JUST cooling the intake manifold on a N/A engine that is pulling outside air, is still worth a performance gain that you will see on the time slip. If it is pulling underhood air, the gain is even bigger.
What you might want to check up on is a water /methanol injection. Uses a base plate like a no2 unit, cools the the intake charge up to 40 degrees and gains up to 20% hp depending on the setup.
Denser air would help, not cooler mixture. The old Pogue carburetors, latter adapted by Smokey Unick tried to superheat the mixture for fabulous gas milege. abe
I believe that. I guess what I should have said was, "Not hot enough to make the naturally aspirated intercooler idea worth it."
You could do an expose tunnel ram intake, and solder copper fins on to it. It would be a lot of work and probably not worth any gain, but theoretically........
Well, yea, I can agree with that, mostly because the gain from cooling the intake will be more than offset by any restriction in the intake tract. I should try to find the article on the Hamburger "Ice Box" intake and post it. It was a neat idea, although a bit of a PITA. NONE of the intake cooling schemes I have outlined here are viable for sustained street use, as the cooling medium will come up to engine temp fairly quickly, but they ARE viable at the track. And I can tell you, it also messes with your fellow racers minds when they see you spraying the intake down with brake klean. 90% of them have no idea what the hell you are up to...
had dashman here on hamb make me some alum spacers &some phelonic spacers for my weiand tunnel ram......he has some for sale also... ask him to make some for the edelbrock tunnel ram too.......
I agree with the general consensus, that it would be counter productive. And I base that partly on driving at sub zero tempretures. Yes, the engine was sucking in some pretty cold air, and no it never seemed to run any better. However, if one jetted richer the denser incoming air might produce a more ideal mixture. Of course you live in Vegas, so you deal with more heat related issues than I do. So go ahead and try it, and then you can tell us how it worked. Good Luck!
I know this thread is a little dead, but couldn't you replace the plenum of a tunnel ram with an intercooler? I know the intercooler will reduce the velocity, but I've heard that with the right combination, you can add carb spacers to increase the velocity of the charge before it enters the cooler, then use runner extensions to recover that velocity? I'm just grinning thinking of a High and Mighty clone sporting huge extensions and that intercooler.
The Jalopy Journal
