Cold air induc...

I'm looking at making a cold air induction type set up in my 2L kombi. I was looking at hooking it up to the intake point on the air box (drivers side). I was thiking of
buying some ducting tube like whats used on the heater fan, not sure were i could get it from? I am thinking about running it up to my air vent on the back and am
stuck on how i could get it to stay there. What do you guys think? would this be better than sucking the hot air in the engine bay? Does anybody have a pic on how to do this in a kombi without cutting panels etc...
cheers

Any effort to decrease the amount of hot air into the induction system is a worthwhile exercise.
Use the biggest ducting you can find/fit.
Ive seen turboed rotor powered drag cars set up with PVC stormwater piping and fittings for cool air inlets.Looks a bit ordinary but works just fine.
L8tr
E

I definitely think this is a good idea. I got some of that type of tubing from the wreckers. I have also seen it for sale at an old skool VW place.

If you can get the tube all the way to the top of the air vent, you would probably have to wire it onto the bars that go across the vent. You will also need to consider is how to stop too much rain getting in!

Good luck with it.

Do you mean putting the ducting into the fan? I'm concerned that might make your motor run HOTTER: the long length of the ducting will slow the air going into the fan, which will mean slower air passing through the motor: so the motor might overheat. Remember that when you double the length of any pipe you double it's resistance. Also remember that the kind of ducting you're talking about has corrugated sides which means turbulent flow which means high resistance which means slower air movement.

One other thing to remember: the air in the engine compartment is already cool anyway, not hot. That's because the fan is continually drawing cool air in through the side vents. Of course if you have missing tinware/seals then the air in the engine compartment won't be as cool as it's supposed to be.

nah, hes talking about putting a duct so that the air cleaner box is gettin cool fresh air. The obstruction in the air vents will give you engine less air and will make it run hotter.

another thing you could try is hook up a 12v blower fan to some tubing at the bottom of the vent (so it isnt obstructing) and then run the tubing to ur intake. personally i wouldnt bother.

Yeah into the air box using 2.5" ducting same that is on the fan. I had a look and
was thinking of running it half way up so as to keep the water away. I didn't think
such a small tube would block to much air flow? I thought by using the ducting would direct the air flow straight in. Is anyone using this or tired on a kombi?
Thank you very much for your feed back you a very helpful🙂

The smaller the tube (diameter) the more it blocks air flow. 2.5" is very small for the length you are talking about (roughly 1 metre). The effect would be the OPPOSITE of porting and polishing the heads: you would restrict the air being drawn into the cylinders and therefore get less horsepower. Don't bother. And like I said before: the air in the engine bay is cold, not hot!

you are all idiots

if the car is carbie fed, it makes no difference with the change of tempurature of the air as its all the same temp when it goes in.
yer sure drag racers have them, and turboed cars, there EFI arn't they

go ahead dont let me put you off, try it for yourself and take notice of there being NO difference whatsoever haha!!!

I dont think being a carburated engine has anything do do with it, cooled air is denser and the more air you can get into the combustion chamber the better.

Sounds good in theory but I wouldnt have thought the engine bay would get very hot as has already been mentioned cold air is constantly being drawn in by the fan, at a rate of 1250 CFM at 4000 RPM!

kevo wrote:you are all idiots

I put it to you that YOU are the idiot here.
!: for being so ignorant and ill informed.
2: Blithely accusing us "all" of being idiots based on ignorance and lack of information.

Here is a little lesson for you big guy.
As mentioned above:
The hotter the air, the less the air density, the less oxygen a given volume of air contains. Less density = less oxygen, less oxygen = less bang.
The cooler the air, the higher the air density. the higher the air density, the more oxygen a given vloume of air contains.
Combine that with appropriate fuel and you get a bigger bang. A bigger bang = more power.
ANY reduction in inlet gas temps is worthwhile provided other parameters such as inlet airflow and engine cooling air are not affected.
Many, many turbo arrangements are NOT EFI, either drawing thru or blowing thru carburettors and there is not one turbo arrangement that cannot benefit by some form of inlet charge cooling (intercooling). Its very cheap horsepower.

There is no black art or magic at work here. Just scientific fact.

So before you go running off at the mouth about what you obviously know nothing about, do yourself a favour and do some simple research.
Saves your embarrasment and ourtime and irritation.
Capiche?
L8tr
E

Turn it up Kevo, idiots!! mate you have alot to learn
i posted this subject and am so stoked on the info i receive back from them, its priceless. These guys have hepled a lot of us out and they are far from
idiots, thats a bloody insult mate!

Chewy wrote:Sounds good in theory but I wouldnt have thought the engine bay would get very hot as has already been mentioned cold air is constantly being drawn in by the fan, at a rate of 1250 CFM at 4000 RPM!

I see your point but I'm not convinced that the air going into the carb is at the ambient air temperature. Has anyone checked? If my beast were on the road I would check it myself as I've got a couple of those digital thermometers with a remote sensor.

(I can see I'm setting myself up to eat some humble pie on this one!)

its probably not going to be ambient but would be pretty close to it. In my bus fan housing has a nipple on the LHS (looking from back) that connects to teh charcoal canister which then connects to the air clean. The fan housing, on a long trip would probably get pretty warm and so might increase the temp 1 or 2 degrees, then the temp of the air cleaner may add another 1 or 2 degrees. pretty easy to see what the temp is tho, just Chuck a thermometer in the air cleaner and see wat temp it is compared to outside temp.

Cooler air to your intake would be good, but as long as your engine is tuned for this denser air, and iam not sure this form of tuning could be done withe car static, could be wrong. Still its worth a try. Also one other thing to think about is, don't have the pipe going directly onto the filter, as if the pipe starts sucking in water/rain/dirt/grit it will go straight through your filter and into the engine. have the pipe dumping cool air near your air intake that way water and dirt/grit has chance to fall out of susension in your airstream.

To be honest, I have never pondered such things as engine bay temps in Kombis, Kombis are just not my thang!
But considering how much air actually is drawn into the fan, the air temp in there would only rise appreciably when the thing was idling on a hot day or recently shut down.

A point worht considering tho is radiant heat from the hot engine hotting up filter boxes and hoses blah.
Not a lot you can do about that unless you shroud the filters and such but id be curious to see how much heating up goes on in there when you take heat soak from the surrounding airbox and tubes due to radiated heat from the engine.

i think Im thinking aloud now...............:jesus

L8tr
E

I certainly am a novice at all of this but have to ask a question, as I have either misunderstood the original idea, or just aren't reading properly.

The reason I ask.....I have been having hassles with a type 1 engine which lacked any 'pre heating', as in, had an aftermarket airfilter and no heated air going into the carby, which I think is standard out of the factory. My problems were certainly during Winter, haven't had to much time to look at it recently now we are entering warmer temps.

Apparantly my carby has been freezing up (or, the contents anyway), and I need to run warmer air into it to keep it from freezing. So, I will be making a setup to do this.

Of course....now I'm confused. I need to run warmer ait into the air filter to make the car run properly (idle, flat spots). But.....as in the above posts, you guys recommend running colder air in?

I am sure I've missed something here and would be glad if someone can explain. I'm not having a go, just trying to learn...and getting confused!

Umm, your setup would prolly be missing the "heat riser" setup where some exhaust gas is passed along the base of the inlet log.
Its usually removed as this aids in performance but can result in the annoying little tuning hassles you are describing.

A lot of older cars have a warm air inlet where the filter snorkel is directed to on top of the exhaust manifold to draw in heated air to prevent carb/manifold icing. They often have a valve thing on the air filter with a "S" and a "W" position (Summer and Winter)

Between a rock and a hard place dude.

Twin carbs will usually cure your flat spots and icing dramas!!

Good luck

L8tr
E

what size motor is that mate. Is there any chance of a pic, might give some ideas
cheers

And we have a winner folks!!!
That's exactly how they were supplied from the factory, and exactly what these two "holders" are for. The factory pipe stopped above the battery though, it didn't go up the air vent inlets to cause any restriction to inflow of air to the engine bay and fan, or allow too much water in when it rains.
see items 17-19
http://www.ratwell.com/technical/Microfiche/t201600.gif
To answer the last part of the question, all reputable VW places will stock the aluminium lined paper tube like on the fan-heater connection (same as factory supply). Alternatively an air filter place will stock nice rubber tube with a wire stiffner the right size which is what I have.

Don't we all love what a simple question can turn into?

:thumb

Felco wrote:in my t2 i have a pipe that runs from the std air filter inlet up to 2 metal hose holder thingos and up the drivers side vent. the hose is about 1mtr long and fits very nice in the engine bay . all that holds it there is 2 cable ties.

nn[ Edited on 21-9-2005 by Andy ]

Well if its good enough for factory its good enough for me! So Andy
i should stop it just above the battery?

Yep, just past the second bracket the hose attaches to.
You never actually mentioned the year of your bus? I assume if it's 2L it's '76 or later?
I know the brackets are there for '74 and later bus's but not sure on earlier ones.
So if your's in a '74 or later body the first bracket is (or should be) just behind the removable cover plate above the RH wheel well (access to the fuel tank filler), and the second around the corner above the battery. Both brakets are up high, close to the rear deck floor (or ceiling of engine bay if you prefer). There is quite a rush of air through there and will be as cool as the outside of the bus.
Just a note, you will need a couple of reasonably sharp bends in the tube, so if you use the paper/aluminium stuff be sure not to kink it.
Oh, I must throw in a disclaimer here, if it was originally an FI bus I don't think it had the brackets. The computer mounted there instead and the air filter was very different as it incorporated the AFM.
:thumb

its a 76 Andy, r u running one mate?

field wrote:its a 76 Andy, r u running one mate?

Not quite sure what you’re asking? I have a stock ’77 2L dual carb bus (amongst others). Yes I run a hose from the intake like stock. Mine is a little short though as I also use it to connect to a pre-filter (dust separator) when I go off road.
Can’t say I have noticed any performance/economy/engine temp. change, but I still prefer to have it connected, every bit helps.