Smokin

I always thought this too. BUT... On a lark I decided to tour their site. They have several Porsche 911s used as examples. I was surprised that anyone would do this to their Porsche. I just imagine the owner telling his buddies that he has a "supercharged" Porsche.

Wachuko

I just kept the stock housing and even went back to the stock filter... I did make holes to the cover, but that was just for the sweet sound it gives back....

Red rooster

You guys should take a look at what racing bikers tried in the 1920s/30s !!
Foward facing horns for free supercharging etc, etc.
Almost none of it worked.
I am waiting for a guy in Florida to have a solar panel conversion idea !!!!

All the best

Geoff

wsybert

No prob on the hijack... enjoy the reading.

wsybert

Well, I was able to check the air intake temperature (AIT) with scantool and a video capture program, and compare the differences of the location of the filter.

FWIW, here is the test:

Old location = under rear deck, with cone filter mounted directly to AFM.
New location = under spoiler, with about 8” long of 3” diameter tubing and 90 deg bend, plus aluminum heat shield under filter.

Drove car to get it fully warmed up.
Ambient Temperature: 50 deg F.
Time of Day: 1:30pm
Duration of tests: 1.5 hours

After a full warmup, drove car about 3 miles at about 60 mph, then slowed to about 30 mph for about a mile, then stopped. Temps looked stable.
Started to capture data from here.
Let idle for 1 minute then drove 30mph in 2nd gear for about two miles, one stop, then ran through 3rd for about 2.0 miles, one more stop, then back through 3rd again 1.5 miles. After each stop I ran it harder.
Stopped car and let idle for about 6 minutes.
I repeated the same steps (as best I could) for both filter locations.

Note: During entire test, except for the final 6 min idle period, I put up the rear spoiler manually. I wanted it to be up for the entire test, since there were stops along the way.

New location:
After initial drive and stable temps and before 1 minute idle, AIT at --62 deg F
After the 1 min idle before moving temps at -----------------------------67 deg. F
Lowest temp recorded during the drive: ---------------------------------59 deg F
Highest temp recorded after 6 min idle: ---------------------------------91 deg F

Old location:
After initial drive and stable temps and before 1 minute idle, AIT at --72 deg F
After the 1 min idle before moving AIT at -------------------------------78 deg. F
Lowest temp recorded during the drive: ---------------------------------68 deg F
Highest temp recorded after 6 min idle: --------------------------------105 deg F

Note: Max speed during the tests was about 75 mph.

Average of all data:
Old Location = 81.5 Deg F
New Location = 70.3 Deg F
Delta = 11.2 Deg F

Average of data while stopped only:
Old Location = 87.6 Deg F
New Location = 75.8 Deg F
Delta = 12.0 Deg F

Average of data while moving only:
Old Location = 72.8 Deg F
New Location = 61.6 Deg. F
Delta = 11.2 Deg F

I guess no surprise that the filter location under the spoiler is cooler, but now I know by how much. At least for this test.

Will have to do this on a warmer day in the summer, but I would believe that the results would be similar.

Next I need to verify the differential pressure from the filter to the AFM with the two setups. Need to see if I am getting a significant pressure drop with the 90 deg elbow.….. hum….where to find a sensitive enough DP transmitter.

Bill

deep_uv

Very cool Bill. Nice writeup.

When you do the next test, how about throwing in a drilled and regular airbox for comparison too if you have them?

Steve

wsybert

I do have my standard airbox, no holes though. Would love to see the difference too. May do that in the spring, when the weather warms up.
May do the differential pressure test at that time as well, to see all three.

N51

Bill,

Without looking it up, your data agrees with Marc's earlier tests. Porsche fitted the cup airbox to cars intended to be tracked(high speed). I wonder if your data and Marc's point to a compromise between street and track. Perhaps one of the two Geoff's can enlighten.

Noah

Jeremy Pinsly

Bill,

Your data are very interesting. Thanks for sharing.

I would be interested in seeing the temperature effect due to just the heat shield, as most people install the cone filter without a heat shield (me included).

Would it be possible for you to make some measurements without the heat shield in place?

wsybert

Thought about that, and ran out of time today.
Will see what I can do in the near future.

deep_uv

Bill I have a spare air box that's drilled, I'd be glad to loan it to you if you are interested in testing it.

Steve

wsybert

I'll send you a PM with my address if you want to send it.
Will put it in the next test, not sure when I will have time, but will try to do it soon.

This means I will have to spend several hours driving my car.... all in the name of science

deep_uv

Got your PM. It'll be on the way on Monday. Cool!

Steve

chancecasey

Now just imagine if you smooth that bend out...

Then again maybe it has a resonance charging effect

Nice work - keep us posted - and it would also be nice to get the differences at some specific rpms - the high ones in particular!

wsybert

The middle part of the graphs were at higher RPM, right before the 6 minute idle period. Nothing sustained, but running out the tach on shifts. I was looking at the data while doing other driving and could not get it to go any lower than the lowest points on the graph.
Anyone know where the temp sensor is? Never looked for it.