Ram Air vs. HAI vs. Warm Ram Air.
 

Almost got everything set up for this test. Hooked up the ram air over the weekend to get the bugs worked out. I should be ready to test all three back to back by next weekend. I will be using a heater core duct taped to my filter box for the HAI and a simple flexable dyrer duct down to the front bumper for the ram air. I suspect that the ram air won't be worth any measureable benefit, but I'd like to test it anyway. If I have time, I'll do a test with just underhood air also.
I intend on testing them all at 50mph, no cruise control, just hold a steady TPS and monitor the scangauge. So what is the best practice in using the ScanGauge for this type of testing? I haven't done it before and am looking for some pointers?

No real input, just looking forward to the results.

I'm vying for the W.R.A.I.Th to win.

So you're going to do 6 different test states, right?

Cold air normal
Cold air RAM
Underhood air normal
Underhood RAM
Warm normal pressure
Warm RAM

Or is the underhood the stand-out test?

I think the OE intake should represent the underhood test, actually. It's the best representation of what the car would normally see, and will allow qualification of any gains that come from either of the other tests.

Preliminary results: I've been running a mild HAI for several weeks and switched to a ram air over the weekend. The result is, it is only slightly harder to attain the same mpg. Definatly don't get as good of mpg, but not really that much worse. Just my opinion...

Hm... seems like the opposite should have taken place... do you have a way to measure pressure drop across your filter media? (vacuum gauges would work fine... )

EDIT: Oops, a vacuum gauge on the dirty side will do nothing unless there is significant restriction there. Chances are, there isn't, since you're playing with RAM air.

Still, one on the clean side will help determine whether the RAM effect is actually doing anything, or if there isn't sufficient pressure to change the intake flow at all.

Is it possible that the RAM is giving too much flow for the RPM's you drive, effectively turbocharging your intake with warm air? That, obviously, would cause more fuel flow, negating the warm-air in the first place.

I wonder - can you watch your MAF's signal in real time? It would be interesting to see a datalog from it, using each type of intake, so we could compare the results and compare the data to check if there's room for improvement or a change in the testing anywhere.

Here's a couple images of the quick and dirty ram air. Just a 4" Dryer duct, duct taped to a 4" PVC 90 degree then duct taped to my air box. Wish I had a magnahelic gauge, but I can try the SG to monitor voltage like you suggested. I also intend on monitoring the ignition advance to find the ideal intake temps, or the temp at which it pulls timing.
I'm not too surprised that the ram air pulling in 30 degree temps is slightly worse than the mild HAI pulling in 80-100 degree temps. The question is, Is the ram air better than no ram air, once you eliminate the huge temp difference, we'll see....

Oh yeah, I forgot about the huge temp difference.

Not to be picking nits, but the ram air is more effective when the entrance is tapered, as in -if you've got a decent funnel to cut, go for it! :thumbup:

If you've got a spare vacuum gauge laying around, you can put a barb fitting in the intake pipe after the filter to get a good reading on pressure change at a specific throttle setting with each type of intake.

In theory, the HAI, then the R-HAI, then the CAI, then the R-CAI should have the least pressure, respectively.

cant wait to see the overall results of this test

Very intriguing!

Some interesting observations from this mornings commute. Woke up to 50 degree temps and caught most of the lights just right and ended up with a 47.2mpg commute, that is what I would have expected from the Mild HAI. Ram Air did not seem to hurt durning this mornings commute compared to yesterdays commute in 35 degree temps. Perhaps were on to something???
Yep, I understand the Ram Air not being fully sealed could be an issue, but I must remind you about the "Quick and Dirty" aspect. It only took me 45min. to make and I had an hour to complete the job. If the Q&D Ram Air proves to not hurt mpg's, then I'll further pursue sealing it up. However if the non sealed version hurts mpgs, then theres no reason to go crazy sealing it up. Just need some Proof of Concept type studies to determine the direction to go that could yeild the best results. Anxiously hoping it doesn't rain this weekend...

Also, Thanks Metro for your timely post on how to do testing :D I'll do my best to follow those guidelines.