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Posted by: Corkus Oct 28 2010, 11:21 PM

If you have a 914 hood vent photo, please show it off.

I took this photo off of a YouTube video for a Rotary powered 914. So far I like this vent best and my Subaru conversion is getting a hood vent soon.

Is this a 911 vent?

Posted by: Andyrew Oct 29 2010, 12:13 AM

Old pic.
From experience I dont think that little vent is going to be enough. You need 2x your inlet size on your outlet.

Posted by: Andyrew Oct 29 2010, 12:29 AM

FYI, Im changing my hood to stock and cutting the wheel wells. Its just not smart for a DD to have an exposed radiator/ exposed trunk.

Posted by: shoguneagle Oct 29 2010, 03:10 AM

I have not completed my air/oil cooler inlet/outlet yet but I am going to use a 996 air diffuser inlet to the cooler. Currently building outlet box twice the size of the inlet which I will either duct up through the hood, or out the wheel area. Although it is not a radiator coolant type, the principles are still the same. Roughly 1:2 (inlet to outlet)

Sorry I do not have any pictures yet but what I hope to see on this thread are different types of hood outlets available.

Andyrew, I am surprised to see you still using the old hood outlet. Great to see that you are still involved and hopefully going to school.

Sorry to hijack the thread.

Steve Hurt

Posted by: jmmotorsports Oct 29 2010, 07:16 AM

I built these for my V8 this summer.

Jerry

Posted by: ripper911 Oct 29 2010, 07:41 AM

Radiator on a 914?

Posted by: d914 Oct 29 2010, 07:47 AM

still in process

Posted by: JRust Oct 29 2010, 07:48 AM

That is nicely done Jerry! Are you goung to have a shroud forcing the air up through the opening? I like it

Posted by: pcar916 Oct 29 2010, 08:01 AM

Under construction

Posted by: pcar916 Oct 29 2010, 08:06 AM

A couple more



The cooler / cell package. I can get the cooler and fuel cell out in less than 15 minutes without draining the oil system.

Posted by: andys Oct 29 2010, 10:01 AM

I don't have any recent photos. Radiator is ducted to this vent, and there's a foam gasket that seals the duct to the underside of the hood.

Andys



Attached thumbnail(s)

Posted by: Rleog Oct 29 2010, 04:03 PM

Beautifully done, Pcar916!

Posted by: pcar916 Oct 29 2010, 08:37 PM

Thanks! It was an adventure since I'm not a sheet metal guy. But my first attempt with the same cooler vented under the car and weakly-ventilated (even with two big fans) was not enough. The 993 motor doesn't have an on-board cooler behind cylinder number 6, so external is all there is unless you dump the second filter console and put back a cooler in that location.

There are more elegant sheet-metal craftsmen out there but this has worked for 10 years (with a small additional cooler in the high pressure circuit during the summer months) so I'm happy with it... zero-maintenance.

There are great examples in this thread. Hopefully they'll give enough ideas to build something functional.

Hood exit rules: Functional 1st
- The closer to the front of the car the better. It's a low pressure zone. Pressure gets higher farther back on the hood peaking at the bottom of the windshield, which is why cars have a vent there that forces air into the interior.

- The cooler intake must be sealed. Intake air WILL escape if not forced to go through the cooler fins.

- Don't make you exit the same shape as mine. I included those little tabs because of the 917 cooler-exit I modeled it after (my all-time favorite Porsche race car). But they're always in the way when I have to use a gas jug and are all bent up because of it. Simple is gooder.

- I should've used -16AN rather than -12AN. The cooler IS -16. I suspect with -16 I wouldn't have had to add another auxilliary cooler.

Class rules: Check 'em. The SCCA regards hood exits as an aero-improvement. If the car didn't come with one it's usually illegal in road racing. I don't think it matters in AX.

It's fun to build stuff.