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burrelks
QUOTE(veekry9 @ Feb 8 2016, 09:05 PM) *

I'm sure at one time,this idea was tried,and found to have too many negative attributes.
Then they did it like this,slowing the cooling air's velocity with ducts.
Small opening to large radiator,just like when Edgar Schmued designed the P51 Mustang's radiator duct.https://en.wikipedia.org/wiki/North_America...and_development
Geoffrey de Havilland did it too,1937 or so.https://en.wikipedia.org/wiki/De_Havilland_...ito#Development
https://www.google.ca/search?q=racecar+cool...r+cooling+ducts
Your choice of intercooler placement seems like a giant slowdown windbrake device,a plank in the wind.
Does your racecar have a passenger seat?A lot of room there,down low in the middle and out of the wind.

Click to view attachment
Create large pressure differentials on the sides of both rads with 'ducting'.
A snorkel duct to the intercooler will get a good flowthrough and temp and pressure diff.
I've seen people use packing tape covered cardboard to try out their ideas and later fabricate them of cfrp.
https://www.google.ca/search?q=fiberglass+o...-VkRSuYFhWmM%3A
https://www.google.ca/search?q=kitplanes+ai...roud+fiberglass
https://www.google.ca/search?q=epoxy+cfrp&a...PxRBNi2EnlnM%3A

idea.gif
https://www.google.ca/search?q=flying+wires...5mIs0kzqkJ0M%3A
The why of it,really.Streamlining of wires,the opposite of the thick foam covering of rollcages.

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Another technique is the stretching of synthetic fabric and epoxy soaking,a layup on the resulting form,or plug.
Sometimes the form is incorporated into the part,as for speaker boxes.
https://www.google.ca/search?q=speaker+shro...nPnDM_1waATM%3A
https://www.google.ca/webhp?sourceid=chrome...+east+coast+usa
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So our car actually has a large circular hole as the passenger's feet. I believe that was used to duct air toward the aircooled vw engine that used to live back there. We could utilize that duct. But for the time being, I just want the car to run/drive/stop. It hasnt moved under its own power for 4 years.
mgp4591
QUOTE(burrelks @ Feb 8 2016, 06:44 PM) *

QUOTE(Rotary'14 @ Feb 8 2016, 07:31 PM) *

Hi Burrrelks,,,

It's good to see your car come together. I count 3 that can start(or pretty close on the forum now.
I have a question for you if you don't mind. Since your car seems to be a race car, why didn't you go with a front mounted radiator? do you have a rear window? or is the intercooler going to be mounted elsewhere? I am wondering what you are planning and want to see if I can add in a thing or two to your project.

-Robert


So I strayed away from a front mount rad because I worried that the water pump couldnt overcome the losses from pushing water way up front and back again.

We fried an aircooled VW engine trying a front mount oil cooler sad.gif

Glass? None. Its all been taken out. (see pic)

If youve got anything to suggest, im all ears smile.gif

There's a few guys that are running an auxiliary electric water pump up front- they're not too expensive and you can easily pull enough water to cool your engine over the length of the car. Check out Mike Bellis' build as he's putting out great power and has a pump up front that works fine. I know there are others but his comes to mind first. You'll find what you need and the front mount is really the most effective way to go.
Mueller
People have been putting water cooled motors into 914s for 20+ years including plenty of rotary motors...your concerns are silly.

I guess that setup will work, but odd placement due to extra weight up high now. Make sure the hot air has a place to go...the exit needs to have more volume than the intake.
veekry9
Back to the Future's DeLorean came to mind.
The square principle,(drag)^2,means the power needed to overcome the new drag is that great.
All known principles,making it smaller,pointier and smoother,an aircraft or car,can go faster with the same power.
Markedly so,the square rule at work.

https://www.google.ca/search?q=streamliner+...SivAOEQ_AUIBigB

Now a 914 into a streamliner hardly works ,but the idea is valid.
A massive reduction in apparent frontal area and wetted surface makes a 'slippery' racecar.


burrelks
Yeah I bet an electric water pump would work just fine.

And the fiber glass trunk lid will likely have a large bit cut out and replaced with like chicken wire, or what the honda civic guys put in the cutouts of their front bumpers lol. Maybe even drill some 2in holes across the back between the tail lights.

And regarding drag, yes, the rule of thumb is that drag is proportional to velocity squared. So at low speeds drag is trivial. At higher speeds it becomes more important. This car will primarily be used for autocross. So itll see relatively high speeds (60-70mph at most)
veekry9
Click to view attachment

A parachute equipped 914,wonder why,maybe it's fast.
Note how much of the rear valance has been cut away.
The exhaust tubing has been tucked up to the trunk floor.
The entire targa has been removed as a drag,the cage closely fabbed around the racer.
The car appears to have a slope,the belly pan lowered in front,the tail still high.
Maybe someone here knows something about this car,still a 2L?
Trying to go fast and break the record,hard to do,to be competitive and win.
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https://www.youtube.com/watch?v=VflfZi4822k


Looked it up,I now recall the car was up for sale for restoration.
http://barnfinds.com/1975-porsche-914-lake...-single-seater/
https://www.google.ca/search?q=bonneville+p...y6HurFLD0NSM%3A
http://www.914world.com/bbs2/index.php?showtopic=225760

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veekry9
Click to view attachment

Wankel
Pronounced: Vonkle.

http://www.airliners.net/photo/RFB-Fantrainer-400/2236582/L/
http://issuu.com/contact.magazine/docs/con...ue_87_rotary_is
http://papers.sae.org/2015-01-0007/--26$,worth it.
https://www.reddit.com/r/oddlysatisfying/co.../wankel_engine/

'An inventor(Ernie Brink) proposed that a narrow linear opening for spark plugs in the housing, instead of the round hole, would improve volumetric efficiency, fuel economy and emissions; he claims to have proved this by recording a measured reduction in the exhaust gas temperature. As in early reciprocating engines, a lower effective compression ratio is linked to higher exhaust gas temperatures.'

https://www.google.ca/webhp?sourceid=chrome...20port%20wankel
https://www.google.ca/search?q=mercedes+ben...+mercedes+benz+

In the '60s,it was the next big thing,a lot of discussion in the drafting/engineering classes.
A bunch of really smart guys have had a go at it,now the next frontier is the use of exotic ceramic materials.
Somehow they all missed the monster compression leak,assuming that 'this is how it is done'.
The asymmetrical combustion chamber too is an obvious advantage.

https://www.youtube.com/watch?v=m3pCLjHZmhM

Reading through the comment stream,it's patently obvious that many have no solutions or valid arguments.
From an engineering point of view,it appears some of them should be somewhat embarrassed.
'Leak?What leak?'
Do you see anything you would improve in the design?
How many sparkplugs is too many?

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