Design of Air intake manifold cooler

I presume you're talking an air-to-air intercooler. You could go to an air-to-water aftercooler, but that would require an ice-box to supply chilled water. Another option would be to regulate the release of compressed air (or ammonia) through the cooler to super (and I use 'super' loosely here) -chill the cooler. Of course, liquid nitrogen would be the ultimate, but I know neither your budget or your tech level.

I'm curious as to your application. I see no reason that automotive air-conditioning system could not be modified either by placing a AC evaporater in the air stream, or by using it to maintain temperature for a liquid source intercooler. I don't know that it has ever been done before, or that you could justify the parasitic drag and weight. I'd be willing to bet if you start checking the racers that utilize turbochargers in competition, if there is an advantage to it they have already done it.

I see no reason that automotive air-conditioning system could not be modified either by placing a AC evaporater in the air stream, or by using it to maintain temperature for a liquid source intercooler. I don't know that it has ever been done before, or that you could justify the parasitic drag and weight

Had a friend who was building a mud bog racer and that was my advice to him. Said it worked great but he owed for the custom lubrication I fixed his tranny over heating problem which he finally payed but never seen it run and he stopped talking to me.

Long time ago and when I did the math then it seemed like (digging in the closet of my mind) it was viable under certain conditions like racing with an underdiven pulley. Close to 20 years ago.

His problem was the ice didn't last long enough.

Brad

Sorry, I should have been clearer.

AC inter-cooler, using hot pressurized fuel into a carburetor giving a dense well vaporized fuel air mass.

The original issue was vapor-lock, fixed by fuel routed through ice for inter cooler. But ice was not lasting before and worse after. Added high pressure electric fuel pump by fuel tank and regulator at the carb to cure vapor lock. The AC inter cooler was to be able to stuff more Air/Fuel into the cylinder without higher boost due to carb issues.

The tranny issue was resolved with Hytorque from Hydrotex or Transtorque from Solutions inc. It's a hydraulic fluid that, like the Duralube commercials runs to heat, and can be used in both wet and dry clutch systems (type A and type F). Mud made external tranny cooler ineffective. You would have to check with the later tranny specs for compatibility.

Brad

All modern semis have intercoolers after the trubo charger. It is an additional radiator placed in front of the standard cooling system radiator.

That is more properly referred to as an after-cooler. Intercoolers exist within the intake manifold itself.

An intercooler would be placed between 2 stages of compression

an aftercooler would be after the final compressor.

If within the manifold it could be fairly referred to as an integrated aftercooler.

If that is the definition then they are all intercoolers - final compression takes place in the engine cylinder. I wonder if automotive convention is diferent than industrial.

My apologies; meant external compression.

i.e.: Turbocharger:intercooler:turbocharger:intercooler:turbocharger:intercooler:turbocharger:aftercooler:intake manifold.

Yes, we have a customer using 4-stage turbocharging.

What sort of duty cycle is intended?

Continiuous, or short term?

Stationary, or automotive, or marine, aircraft?

I'd be tempted to avoid the complexity of a mechanical chiller.

For 'drag racing' iced water in a liquid/air aftercooler works well; As does the rapid expansion of compressed (stored in a tank)gas, either N20 into the airstream or CO2 into the jacket of the aftercooler.

Latent heat of evaporation of the fuel itself is quite useful here, particularly if using an alcohol based fuel; this can be applied to any length duty cycle.

For longer run times the coolers that transfer hear to the envirinment are more practical. Air/liquid/air systems will often package more effectively as the 2 halves can be mounted at a distance from each other.

I've had discussions with some racing engine builders about installing an aluminum heatsink in the airflow path with a number of Peltier type thermoelectric coolers mounted on it. The problem with using an AC compressor to cool the intake air is that the horsepower required to drive it is greater than the HP gain from the cold air.

Now I suppose if you had a large enough tank of pre-compressed air you could inject that into the intake and the self-refrigeration combined with the increased pressure could serve too. But this would only be good for drag racing or something with a low duty cycle.

There are a number of more cost effective methods to cooling the air/fuel charge then adding auxilliary cooling devices.

For one, how does your engine cool itself? Many engines cool the block first, then the cylinder heads, then the intake manifold and then back to the radiator. Modern V8's, such as the chevrolet LT and LS series, cool the intake first, then the cylinder heads, then the block, and back to the radiator. Not only is the intake manifold thus cooler, but the heads can utilize higher compression and more timing. The good news is if you are running an older engine, many can be retrofitted for a reverse cooling pattern. This is the same setup used in modern police interceptors as it gives better endurance qualities to the engine.

Many intake manifolds also have an exhaust crossover used to intentionally heat the manifold in carbed applications for easier starting. These are usually eliminated in racing/ high performance applications (in fact, many aftermarket gasket kits include blockers for these exhaust passages)

A bigger, aluminum 4-core radiator and proper thermostat selection can make a huge difference as well.

A phenolic spacer between the carb and intake reduces heat transfer to the carb from the engine.

No serious race or high performance engine runs an A/C setup. None. The parasitic loss on these can be higher then 10% of the total engine output, which is more then you'll get from a 1-2 degree drop in temp.

A baffle plate in the lifter valley below the intake manifold in a V-configured engine will reduce the amount of hot oil hitting the intake manifold.

Some people have claimed performance coatings such as ceramic on the headers and intake help lower temperatures as well.

Edelbrock makes a series of intake manifolds which raise the plenum and runners off the intake mounting surface so air can pass underneath, I believe they are called "Air Gap" manifolds.

Everything I have mentioned so far is cheaper then a water spray or aux cooler setup. Remember, Detroit was putting out 400+ HP V8's and 300+ HP 4 cyls decades ago with all cast iron parts, solid lifters and conventional cooling systems. If you can't achive this with the setup you've got, adding more cooling is like putting a band-aid on a chest wound. Cooler temperatures arent always better in terms of fuel volitillity and combustion either!

In my mind, if you choose to use a power adder such as a turbo setup, the neatest idea I've seen is mounting the turbo at the tailpipe. I forget the name of the company, but they make essentially a turbo/muffler combo that routes the air charge along the length of the car to the engine. Its easy to imagine putting fins on that tubing and achieving an appreciable amount of cooling without the added expense.

Avery Montembeault

As for the remote turbos are you referring to STS?

http://www.ststurbo.com/

I have no connection to these guys and this is by no means an endorsement.

I know this may be a dumb question but my curiosity has me peaked and hopefully with all the knowledgeable gear heads around here maybe someone can help. I have a boat that has a hopped up engine that is running a Barry Grant 650 CFM carb (no forced induction). In Texas during the summer the air temp can be 100 degrees and the engine is raw water cooled and the lake water can also be approaching 90 degrees. Run the boat around for 30 minutes and shut off the engine for another 30 minutes then lift the engine cover and it can reach 275 degrees inside the engine compartment. Tons of heat soak and the excessive heat will cause a little fuel to perculate out etc. It gets so hot under the engine cover because unlike a car/truck that has a radiator in front that air can flow thru or is open on the bottom under the car/truck which allows a breeze that can blow slowly allowing heat to escape and the engine to cool off. In a boat in the summer after you have run it for a while and turn the engine off, the engine will be very warm even the next morning. The engine in the boat is sealed up tight on the sides, top and bottom and when sitting still there is no air at all entering the engine compartment...just stale hot air which takes much longer for the engine to cool down. Since I have no radiator and an endless supply of fresh water, I saw a neat water to air intercooler kit for around $300 for engines up to 600 HP. Would be very easy to install and run water thru it...no problem there as I don't need a radiator, just tee off the water inlet hose, run to the IC, exit the IC and use a pisser on the hull to dump out the water. My question is...can you even run an intercooler with no forced induction? Without forced induction will a 650-700 CFM carb be able to pull air thru an intercooler fast enough or without forced induction does the intercooler just act as a restriction causing havoc with the carb?

I am assuming that the carb does not have the force/signal to pull air thru it like a SC but I just had to ask some of the pros around here with Forced Induction and intercooler experience...anyone care to comment (I hear laughter)???

http://www.frozenboost.com/product_i...268c039297a964

http://www.frozenboost.com/product_i...268c039297a964

Just guessing here but I would say no. It would probably be too restrictive and there would be a net power loss.

A better idea would be to ventilate the engine compartment with some 12 V fans. That is if it's possible and you don't object to making a hole in your cowling. You could also construct or probably by a fuel cooler, that is run your fuel line through it and circulate the lake water around the outside of the fuel line.

The last and probably best idea is to move to California, the air temperature may be high but usually you can get cooled off jumping into the water. And whatever you do don't have an Aggie engineer your system.

Just kidding, I like Texas but as they say it's a good place to visit but I wouldn't want to live there. I've had three unscheduled layovers in Midland Odessa (if you know where that is) years ago there was nothing there but an airport ,motel and a restaurant and the restaurant closed on Sunday. On two of the three incidents all separated by seven or eight years a little old man in a 64 Plymouth valiant pick me up and stranded me at the sky Park motel.

The last I was flying a light aircraft, got fuel at Wink so I wouldn't have to landed at minimum Odessa, whether forced me to land there any way. Thank goodness they built a new motel there, if the little old man had showed up one more time I'm sure it would've been the twilight zone.

PS, I can't mark this is off-topic or you wont be able to read it with only guest privileges, so hopefully I don't get court-martialed by the administrators. This is a relatively old thread and you may do better posting a new question in the general area. You should think about registring it is pretty easy. And you won't have to depend on Aggies for engineering. Just kidding love to rib Texans.

I strongly concur with ywroadrunner, well at least the part about ventilation, not about living in Texas (Houston and east texas is quite nice. Nothing at all like Odessa). In fact I would suggest that if it is hot enough that you are evaporating the fuel from the carb bowl, then you have an explosive situation in the engine compartment and you should be power ventilating (with an explosion-proof Class 1 Div. 2 blower) the engine compartment for several minutes (15-20) prior to engine start and continuously during operation and for several minutes after shutdown. This is not as big a deal with diesel boat engines since diesel is not that explosive, but this is a common problem with gasoline powered boats and there have been a number of explosions and fires as a result. Gasoline fumes are EXTREMELY explosive. One gallon of gasoline, properly atomized, can take out a city block. The couple oz in the carb bowl is certainly enough to do plenty of damage to your engine compartment.

You could also insert a thermostatically operated electric water pump into the cooling loop to make sure you keep circulating water through the engine block after shutdown too.

Hello Rorschach: running late I just have time to say a quick hello. I wanted to thank you for correcting my oversight , I failed to warn the poster about gasoline fumes, which are particularly problematic in boats at times.

1 pint of vaporized gasoline equal four sticks of dynamite. I got that figure from a safety film in high school auto shop where they showed a boat blowing up. Must've made an impression I can still see that boat flying a part 35 years later.

Any rate thanks again. By the way ribbing Texans is a national pastime, must be the Aggies. But seriously I of met a lot of good people there

I've been stranded in Midland Odessa, 1973, 1980, 1986 and in 2005 I was on a commercial flight that made a emergency detour and was stranded overnight in Texas again. (Thank goodness not Midland Odessa) Next time I visit mom in Alabama, I'm driving , or flying around Texas.

I used to have a postcard sitting around here that I sent my wife when I was stuck in Midland in 1980. The front picture was a dilapidated model T with a vulture perched on the windshield. On the back there was a sign that said welcome to Midland Odessa,tourist wanted, no experience necessary.

BTW. Condolences on the Aggies. Heard five drove into a lake and drowned. The two in the front of the pickup couldn't get the doors open. And the three in the back couldn't get the tailgate down.

In YOUR case, i'd: 1) Provide an external source of cool air for the induction system, 2) maximise the bilge blower system (you ARE using one?!?!?!?), & 3) apply a watercooled manifold (exh).

Shutdown temp rise might be best dealt w/ using an auxilliary, electric waterpump, continiuing coolant flow after engine shutdown.