At the DE today at Firebird Raceway, there was one very quick 2.0L 914.

I met and talked with the owner John Seymour for awhile. One of the innovations he came up with really looks interesting. Instead of the stock air filter box. he looked for a way to get cooler air into the motor. Study the photo (I have more if you want me to post). He ran a PVC pipe from the TPS to hoses that go down to the J tubes. From there they are connected to the air ducts in the longs and finally, he is pulling air from the opening in front of the windshield. He claims it works like a charm. I don't doubt him, as he is running D-jet and was as quick or quicker than the 2.0L cars that had been converted to carbs.

its cool if you dont need heat.


i give him props for making that up from what he had though.



b

Oh yea, the car is listed for sale on the AZ Region PCA web site:

FOR SALE: 1974 914 2.0
Black/Black AX and DE car. One of the fastest, best handling 914's around. All of the latest tricks. Many $K's invested. Not registered for the street, but clear AZ title. Originally a CA car. Extra wheels/tires. Lots of spare parts. Can be put back on the street, if desired. $7500 obo.
Contact: John Seymour
Phone: 480-987-6508

The car is factory black and John says the former owner painted black over yellow. The VIN is correct for a Bumble Bee, so I have forwarded that information to Jeff.

One more. Notice the venting for the oil cooler in the hood.

a bumblebee?

Yep, a Bumble Bee. VIN fall right in the middle of the run, correct black paint code and production date within the known time range. I gave the basics to Jeff, I will let him be the final judge if it should be added to the list or not.

I'm a bit confused as to how the air goes to the cylinders..more pics, please

Now if he put a little scoop over the front air vent he'd have RAM air!

QUOTE (Hammy @ Nov 14 2005, 12:49 AM)

I'm a bit confused as to how the air goes to the cylinders..more pics, please

the normal way....


the unique thing here is that the air "supply" is now being taken from the engine bay through the J-tubes....and through the longs (where the heating ducts usually are) and into the front somewhere.....

colder air = more dense = more oxygen = more BAM!


b

Does that actually work or is all the piping a restriction? Plus the tubes must get pretty close to the exhaust on their way up. I am guessing negligible improvement if any.

I agree, probably negligable.

You want cold air? duct it to the top of the car, or the sail pannels(my pref).

I agree on the scoop...

but hey, if it works

Does it work? He says he is running a stock fi 2.0L and he is quicker than the other 2.0Ls, injected or carbed. While at speed, I would think that the air running through the tubes would not have time to heat up much when passing by the heat exchangers. Does he get enough volume? The size of each of the two tubes is bigger than the opening on the factory air filter box, so I would think volume would not be an issue.

Interesting idea.

Cooler air makes more power, no matter the engine- as long as enrichment is correct for the given air temperature..

Look at all newer cars, they have fresh air intakes from the front of the vehicle- thats why, the engine bay gets hot and hot air doesn't make power.

This is also the reason I have fresh air intakes into my dyno just for the carbs/ Throttle bodies.

No provision for an air filter is seen. In my opinion not a good idea to run that way, unless you like scuffed up pistons and bores.



dirt is an engines enemy

There is no doubt that cooler air can make more power, but does this set up make more power?

Seems like a lot of work when something else that is simpler may work also. I've seen where guys will take sheetmtal or f/g and seal off the top of the engine compartment and stick the air intake thru the sheetmetal so that only cooler air is pulled in.

Or why not take the engine lid off on track days and stick a 24" piece of PVC pipe on the intake and tie it to the targa bar/ roof? At least it would be less work.

If he thinks it works and he's happy with it I guess it doesn't matter. This is the new kinder gentler me.

It doesn't look like it has very much volume to me...

The fresh air box ahead of the windshield sees higher pressure air than the engine grille, probably enough to make up for the added drag through the tubes.

QUOTE (dmenche914 @ Nov 14 2005, 08:14 AM)

No provision for an air filter is seen.  In my opinion not a good idea to run that way, unless you like scuffed up pistons and bores.  dirt is an engines enemy

I would think the air filter would be at the end... probably right under the fresh air intake grill. Or at least I hope so!

old school drag racers used a cool can to chill fuel before it goes to the engine.

New school guys use intercoolers for the air.

I always thought using a cool can (chilled water in an intercoler would be a great idea...

really condensing the air for max power.

QUOTE (rogergrubb @ Nov 14 2005, 12:42 PM)

old school drag racers used a cool can to chill fuel before it goes to the engine. New school guys use intercoolers for the air. I always thought using a cool can (chilled water in an intercoler would be a great idea... really condensing the air for max power.

i agree -- i'm thinking some sort of dry-ice packed fuel cooler + some ducted air from the sail panels or targa top could be worth a few hp, particularly on a hot day.

So what's the conclusion...does it add power?

QUOTE (Hammy @ Nov 14 2005, 03:14 PM)

So what's the conclusion...does it add power?

dunno, too variables to be an arm-chair engineer, only testing would prove/disprove it.....

I'm guessing if it didn't work, the owner would have removed it by now since it sounds like he's been running it for a while....

Most of the time an intercooler is used in a turbocharged car, b/c the compression of all that air genereates a lot of heat. Since the compressed air is so much hotter than ambient, its (relatively) easy for the intercooler to extract some of that heat. I would think that on a N/A car, there's not much use in an air/air intercooler, since the air doesn't (shouldn't) get that hot anyway; just make sure to grab the air from some place cool.

Going *below* ambient should also increase power, but it gets down to a question of practicality. ( Actually, part of the boost from nitrous is due to cooling : just like when you let air out of a tire or use a spray can, the nitrous gets cold when you squirt it.)

I haven't heard about dry ice being used. Although it's cheap, safe and easy to get a hold of, the big problem is that its a solid, so its hard to make a good thermal contact with, say, an inlet air pipe. If somebody wanted to mess with something really crazy (i.e. : I'm not saying that its a good idea), you might try mixing dry ice with acetone. This combination forms a slush (like rock salt and ice in the old ice maker) at a temperature of -108 F. So you'd need a container that doesn't leak, doesn't turn brittle at low temp, and allows the CO2 to boil off without exploding. Run your air pipes through there and I'm sure you'll feel some extra oomph, at least until the dry ice is gone.

flow rate could easily be increased with two of the aftermarket blowers made for vw heating systems. Put one on each side, towards the rear so it would pull from the front and give a little boost just before the intake. I've thought about it befor but I was thinking of running it through the firewall and then through the center tunnel. Pvc in the tunnel, flex pipe at the walls.

Heres my response to your PM srbliss
I couldnt get my internet to let me send a pm... its on the fritz right now... sorry
Others might also know.

"Hello Andrew,
I think we met at the metalshaping class a few months ago.
I have an odd question that only an engine swap guy with a running car could answer. What direction does the air flow in your engine compartment? I was hoping to get you to do a quick test next time you drive your car - if you don't mind could you tape a sheet of paper or cardboard on your air intake (grill) and note if it was sucked down or blown upward by the air flowing (if it flows at all) thru the engine compartment."

I am asking because I am starting a Subaru engine and transmission swap and would like to setup the radiator in front of the engine and use whatever natural air flow that exists.
Thanks
Steve.


"I'll give you a quick answer and send you another answer a little later.

I currently have the factory sweeper things that used to go in front of the engine under the car, 72 plus cars had them, they throw air onto the bottom of the engine. That said, I do not think there is much pressure what soever at the engine grill. I think that all the air gets sucked to a medium by the headers and then gets thrown out the bottom of the car, and the air that is from the top of the car just goes right over the grill.

I'll get a piece of paper and test it out in a little.

Andrew"

hey ........ why not run hoses to your ac vents and crank the ac to high?!?

here is a bimmer air box i saw at sebring.

QUOTE (scotty b @ Nov 14 2005, 05:28 PM)

flow rate could easily be increased with two of the aftermarket blowers made for vw heating systems. Put one on each side, towards the rear so it would pull from the front and give a little boost just before the intake. I've thought about it befor but I was thinking of running it through the firewall and then through the center tunnel. Pvc in the tunnel, flex pipe at the walls.

That's really just a supercharger, but powered indirectly (and inefficiently) via alternator/wires/motor instead of a belt. If the fan motor is wimpy (like a VW heater blower) you aren't really gaining anything noticeable in terms of power. If it's not, you are placing a huge load on the car's engine (and alternator). In general, a supercharger is less efficient than a turbo, b/c it takes "good" energy to drive it (from the crankshaft) as opposed to "bad" energy (from the exhaust stream). So says Corky Bell, anyways.


The problem with this kind of thing, is that to get any significant increase in power, you have to increase the number of O2 molecules significantly. Just wafting them along through a tube won't cram many more of them into the cylinder. To get a feel for it, imagine using a bicycle pump to pump a car tire from 0 psi (gauge) to 10 psi (gauge). It's no manliness contest, but it does take a little time and effort. Compare this to a decent turbo setup which runs at 10 psi of boost. Since atmospheric pressure (for you lowlanders) is about 15 psi, that means an increase of around (25/15 -1) or 65% in oxygen going into the engine. So, ignoring lots of details, you get around 65% more power. Now for a 2.0L engine at 3600 RPM you breathe (3600/2 /60 * 2.0L) or 60 liters of air per second. Thats about 16 gallons of air. I don't know the volume of a car tire, but it seems rather less than 16 gallons. And 3600 RPM is kind of timid. But just imagine having to pump that tire up to 10 psi once per second, and you get a feel for the kind of job a turbocharger (or supercharger) has to accomplish. If you try something that's wimpy compared to a turbo/super charger, you'll get a result that's wimpy as well.

Using cool air, though modest, does help. It's like letting nature take care of all the hard work ahead of time. Working in absolute (Kelvin) degrees, density is proportional to temperature, if pressure is held constant (like atmospheric, fer example). So going from 55 C down to 35 C (i.e., 131 F down to 95 F), which is a 20 degree diff at (273 + 35) K, gives an increase in O2 (hence HP) of 6% without expending any effort.

QUOTE (scotty b @ Nov 14 2005, 04:28 PM)

flow rate could easily be increased with two of the aftermarket blowers made for vw heating systems.

Hey, just keep adding more and more blowers and you'll have an electric supercharger!!

I think you'll find the fans will impede flow at higher velocites, so your engine may get a little boost down at low RPMs but it'll be choked somewhat at higher revs.

--DD

I think you neighbor's alredy got a patent on it.