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The project was a success

I was unable to find the thread I started the discussion in, so I’ll beg your forbearance for starting a new thread.

I mentioned that I was considering creating a ram air system in my 2005 tC. Well, the final project is done and the results in. In summary, I:

  1. increased the air intake snorkel capacity by 20% by replacing the snorkle with flexable hose (shop vac hose) of greater diameter.
  2. removed the cap on my left front vent and replaced it with a homemade grille, providing a true cold air source for the engine
  3. created an “air chamber” into which the cold air flows when the car is moving, including drainage for water
  4. dropped the new snorkle intake to just above the inflow of cold air
  5. added a “velocity cone” (which should actually be called a “compression cone”) in homage to Bernoulli (like we used to put on “velocity stacks”)

So now I have true cold air feeding a snorkle of increased capacity, possible under slightly elevated pressure.

It turned out that the cavity behind the left front vent was all plastic up to the top of the wheel well, so creating a chamber out of that seemed more logical than my original idea of adding an air box.

Anyway, it worked. There is a definite performance improvement, particularly when travelling above 30 mph, with no adverse effects. The engine even sounds better. Testing with a garden hose and then miles of highway driving in heavy downpours showed absolutely no water to be drawn up into the air box.

Just as an FYI, I also installed a TRD rear sway bar (a definite reduction in lean and understeer) which really tightened up the handling, and I replaced that bean-shaped rubber shift know with a Titleist #1, my dad’s favorite. I was simply unable to find an old fashioned cueball-colored shift ball. An old-fashioned ball simply feels much better than the new ergonomic shifters they’re installing now.

The project was a success. And I’ve honored my dad and Bernolli both. Now it’s on to my next challange. That’ll be to find affordable pressure and temperature transducers to drop down into the cavity and see what the actual changes are. From there I may even “tweak” the cavity, but in truth I just want to learn exactly what all I’ve changed and by how much. Its one thing to create a change, but even better to understand it.

Neat! How about a simple water u-tube (clear plastic hose) for pressure measurement?

I’d be interested to see comparitive dyno charts :wink:

I’d wager your performance jump comes from the CAI far more than the ram component. Heat soak in modern engines is insane. If you stop at a light for more than 10 seconds on a hot day your performance drops noticeably.

RE: cueball shifter: Make your own! All it takes is a cue ball and a drill press.

That would work. A simple manometer.

I was hoping to find meter with perhaps a piezoelectric transducer and a temp transducer so I could use one meter, readily stick the transducers into the cavity, and measure both readings on the fly. I’ll have a friend write down the numbers while I concentrate on driving. My guess is that one with a recording capability would be cost prohibitive…but in truth I haven;t looked yet.

Or, if one of you General Aviation types has an old aneroid altimeter lying around…i’ll be happy to take it off your hands.

The ram effect won’t show up on a dyno, the car has to be moving at a high speed for the ram air to have any effect.

Thanks Shadow. I actually bought a set of pocket billiard balls with that intent, but the cue ball was larger than felt comfortable. I seem to recall that the English billiard balls (for biliiards without pockets) are small, but I haven’t found any. Even to get the pool ball I got I had to buy and entire $38 set of balls.

I did learn, however, in doing the Titleist, that a thread tap (dry) works on hard rubber golfball centers!

Try a British snooker cue ball…they’re relatively small

I know, Keith, I plan to be moving when I take the measurements. I hope to call out each 10 mph increment and have a passenger record the readings.

But first I gots to find an affordable measurement setup!

Thanks Chaissos, I’ll definitely check that out.

I was referring to shadowfox’s comment about dyno charts.

Got it. Thanks.

I have to admit that a dyno would be nice too, if I could set one up in a wind tunnel. Ther might even be a slight difference even without the wind factor, just from the increased snorkle capacity, the access to ambient air, and the Bernolli bell. It would veen be a valuable reading to determine axactly how much of the increase is attributable to each of the variables.

Understanding the changes is going to cost more than making them!!!

There are ways to dyno test a ram air setup. One shop uses twin 185 cfm air compressors designed to run jackhammers to pressurize the airbox to simulate the ram air effect. That requires some faith, though, that the pressure you select is indeed the pressure that will be present in the intake due to the ram.

I’d probably just stick a variable speed fan capable of moving air to at least 100mph and stick it in front of the car, then hook the speed control into the dyno.

I’d go with a variable fan and a wind velocity measuring device on the intake. I’d simply control the wind speed manually based upon the speedo reading rather than trying to corrolate it with (and control it with) the dyno. Simple and direct.

But the point is well made, it is possible and not overly complicated to simulate the air coming in.

Just tried a search…this ain’t gonna be cheap!

Looks like I’ll have to see what I can borrow.

Hmmm, probably haven’t put enough thought into this but my first thoughts were along the lines of fitting in a pressure transducer when i thought- why? you already have an excellent sensor in there- the MAF. A decent OBD tool will be able to display readings from the MAF and you’ll know the relative increase in “air” available with your modifications.

Temp is super easy with a thermocouple on a simple DVM. Temp and pressure are related so you kind of get those combined with the MAF reading and the only really important reading is relative number of O2 molecules per volume of gas anyway.

Have you tried a bumper Pool Ball for fit and feel? I think they are smaller than a standard billiard ball. And I see bumper pool stuff at yard sales all the time.

Perhaps using the ECU, MAP sensor, and intake air temperature sensor from a 96 or later Jeep would work for you. You could then read out the numbers using a scanner. I stated Jeep since I believe it uses both those sensors. There may be others also.

I Hope Your “Titleist #1” Isn’t A Pro-V 1That You’re Drilling Holes Through.
What A Waste, Breaks My Heart. Couldn’t You Just Make A Top-Flite Or Max-Fli Work ?



Pvt, I checked into bumper pool balls. They’re smaller that snooler balls, but still too large, and need to be bought as a whole set…$$$$$$$$$

Cougar, that’s in interesting suggestion, but for temp the simplist way is a simple thermocoulpe and DVM, as TT suggested. Trouble is, I got to see what I can borrow. Thermocouples come in a number of different standard couplings, each designed for different temp ranges and putting out its own curve, and the T-couple and DVM need to be a calibrated set.

I did just realize, however, that I have a bunch of old General Aviation aircraft instruments in piles in storage about 100 feet from my office. I’ve need to talk with the guys and see if they have a pressure gage they can loan me.

A MAP reading would be interesting, but I have nothing to compare it to. I can measure an increase in pressure with velocity of the vehicle, I can measure the cavity temperature relatiive to anbient and the underhood temp (and see that the temp in the chamber is actually at ambient, and I’ll have enough to prove that the system is effective.

I’m actually confident in the temp. I’ve since wrapped the incoming tube, the air cleaner box, and some of the induction system in heat shield insulation, and after a 50 mile highway day yesterday I felt the air cleaner box and it was still cool.

CSA, it’s just a Titleist #1, in tribute to my dad. Nothin’ but the best.

For the record, I have in my hands a General Aviation Airspeed Indicator. With that I can detect pressure increase and see if I’m actually creating pressure in the chamber.