posted 08-18-2003 12:40 PM                  

Cruising at 75 MPH with an outside (ambient) air temperature of 85 degrees F., my CAI was sucking 145 degree air. This is with the A/C on. Turn off the A/C and the air temperature drops to 135 degrees. Slow down to city driving with stop lights, it is sucking 165 degree air. So much for CAI. It needs to be called HAI (Hot Air Induction).

We need affordable side panels that enable outside air temperature to enter the induction on the Prowler, and also look great.

posted 08-18-2003 04:55 PM                  

If it's not too much work and if at all possible, try to check a stock air box with a stock air cleaner or a K&N filter while doing your tests.

The stock Prowler airbox snorkle picks up its air at the front of the passenger side door instead of the engine compartment.

posted 08-19-2003 01:20 PM                  

Yes, I may try the stock air box, if I can remember how it goes on the Prowler. It has been several years since I removed it. I believe that there would not be much difference in the inlet air temperature between the stock box and the so-called CAI that I have, because my CAI draws air from the right side panel and right side door jamb (just as I remember the stock box doing). If the CAI has any benefit at all, it may have less air restriction. I have no way of measuring that.

I would like to try cowl induction, but have not been able to figure out how to get air into the intake plenum, which is at the back of the engine. There is little clearance between the firewall/tub and the inlet. I don't want to cut the tub or the hood, but feel if you could make a wide air horn between the inlet and where the hood meets the tub/firewall and filter the inlet, you could improve hot weather performance since the engine would not be sucking preheated air from the engine compartment.

posted 08-20-2003 07:33 AM                  

I am interested to see if the problem of increased heat of the intake air in the CAI is offset by the increased volume of intake air that the CAI offers.

Which do you think is better? Restricted cold air stock intake, or freer breathing CAI....but the air is warmer than stock???

(I have the MTD intake.)

posted 08-20-2003 05:43 PM                  

Black Tie 161, I believe that the temperature of air going into the filter is much more important than the hopeful increase flow that a so-called CAI can provide you (free flow) over the stock air cleaner.

If a 3.5 liter engine is running at 3000 RPM pulling air through a round 3" duct, it requires around 185 CFM. If the duct is 20" long, the temperature rise would be around .03 degrees F. rise at this CFM. So, the air temperature entering the throttle body is nearly the same as the air temperature at the air filter.

I believe there is no difference in the air temperature entering the CAI vs. the stock air box since they are sucking virtually the air preheated engine air.

The Prowler engine is built as a thermo runaway device. That is, the hotter the engine is, the hotter the air around it is. The hotter the air it is sucking, the hotter it runs. The hotter it runs, the hotter the air around the engine is. It is like cooling transistors! Right, Mike?

posted 08-20-2003 10:54 PM                  

I had read on an earlier post that removing the rubber seal, which is, found at the top of the firewall ads lots of cool air into the engine compartment.

It’s the seal that touches against the base of the hood. The seal comes off easily and can be reinstalled in seconds.

It would be interesting to see if any temp difference is measured with or with out the seal.

Please keep us posted on the experiment.

posted 08-21-2003 08:18 AM                  

Don

posted 08-21-2003 03:44 PM                  

Koastal Cat, tomorrow on I-75 from southwest Florida to Pigeon Forge (700 miles), I will measure the inlet air temperature to my CAI with and without the gasket that goes between the back of the hood and the firewall. I will wait until the ambient air temperature in mid-day stays the same. I will report my findings when I get back.

This idea is not mine. Ted Mathieu of Palm Beach, FL should be credited for this. He did not, however, measure the temperatures at the inlet to my knowledge.

Black Tie 161, I believe that we may be able to fabricate an air horn between the throttle body and the upper lip of the firewall/hood (with the rubber gasket removed) to take in ambient air. The problem is, where to put an air filter. Maybe at the drag strip, install the air horn with no filter just for racing.

Northern Cat, I will also bring a spare thermocouple with a remote readout.

Today I put the spare thermocouple on our new Infiniti FX35 air inlet (280 HP V6 4000 lb. AWD Crossover). The air inlet on this vehicle is between the front edge of the top of the hood and the grill. The air temperature was 3 degrees warmer entering the air filter inlet than the ambient temperature!!! On my Prowler, the difference between inlet air temperatures is 60 degrees higher than ambient air temperature, under the same driving conditions! (Speed and ambient)

We are driving a thermo runaway machine.

posted 08-30-2003 06:45 PM                  

Very interested in the results!

posted 09-01-2003 04:17 PM                  

At the meet in Pigeon Forge, Bob Goetz of Real Rod kindly let me test two different side panels. The test was conducted at 85 degrees ambient with only the right side panels at 50 MPH. I was trying to quickly test each panel while the temperature was the same. For this reason, I could not drive 75 MPH for an extended test close to the hotel. I believe that the following temperatures would be lower if I could have been moving faster, and if I had matching side panels on both sides of the Prowler. (The stock panel remained on the driver's side during the three tests).

Findings:
1. Stock panels, inlet air temperature was 125 degrees.
2. TGF Engine Side Panel available from Real Rod was 120 degrees.
3. Ram Air Side Panel available from Real Rod was 115 degrees.

Again, I feel if the test was at 75 MPH, the inlet temperature would have been down another 10 or more degrees with the modified side panels.

While getting to my test section of the road during all three tests, I noticed that there was no difference in inlet temperatures at stop lights (140 to 160 degrees). This means that the Prowler has to be moving to get cooler air to the inlet.

Bob said he may build an air scoop to direct outside air from his panels into the air filter. This is what we need! Thanks to Bob Goetz for letting me test his panels.

posted 09-01-2003 06:56 PM                  

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