Intake Air Temperature Testing

Set up to do some tuning (laptop hooked up and temperature probes connected):

My first temperature experiments were made on 8/5/03. I used two cheapy (~$30 each) Radio Shack indoor/outdoor digital thermometers.

I have a k&n filter located right beside the SC and no heat shielding on my exhaust manifold or SC. I also have the MidTenn fixed headlight assemblies with the lens covers removed (should allow lots of air under the hood) and no plastic under engine pan. I mounted my temp sensors in three places (see below) and can see my intake temps from the link ecu (after the intercooler). My coolant system has had no piping modifications but the radiator has been replaced with an all metal unit. My 6 temps are:

1) The space behind where the wiper motor goes (where the vent gets its fresh air - completely sealed off from the engine bay)

2) The open space beside the intake manifold where the washer bottle normally sits (a nice open space to put an air filter)

3) The top of the K&N filter (again, right smack beside the JRSC)

4) NORMAL In-line measurement between my A/W IC and intake manifold (when not under boost)
5) MAX In-line measurement between my A/W IC and intake manifold (when under heavy boost)
6) Coolant temp

Some loose averaging out of the temps show:

1) 85* (pretty much ambient temp)
2) 100* (stayed about 15* above ambient)
3) 105* (always stayed 5*-10* above the cold-side)
4) 110* (was only 93* when cruising at 3500 rpm after some spirited runs)
5) 140*
6) 198*

My initial thoughts on this data:
1) My IC works pretty well. After all the pedal mashing I did I only got the intake temps heatsoaked to 100. That's only 15 above ambient and could probably be improved with out too much trouble.
2) Behind the wiper motor is a great place for an air filter. Wonder what 15* cooler intake (before SC) would do for my power?
3) Beside the SC is not really as hot as I thought it would be. Would shielding the SC with insulation hurt it in some way?
3) Its 5* hotter in the cabin (ashtray cup holder) than behind the wiper motor
4) My coolant system works fairly well
5) I'm going to get a ticket if I keep driving like this

As I do further testing and design a CAI system (cold air induction) I'll post further results.

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Water Injection

Even though I have an Air/Water Intercooler I have started testing my "Tom Graham" DIY water injection system to get further cooling. Many thanks to Tom for the inspiration on this!

Ok, just did my first test run with the new water injection. I had one problem with the system and that was water leakage. When I built it I did not use the correct "goop" and that cause quite a bit of water leakage (spraying on the underside of the hood instead of into the intake). I'm in the process of re-gooping and re-testing. Even though I lost a lot of water I did get some data but I am not sure what it means. Note that the WI was activated manually (no pressure switches) and used for the entire time I was under boost.

Without water injection:
Boost peak @ 4100 rpm = 8.6 PSI
Boost peak @ 7700 rpm = 9.6 PSI
Air temp increase during boost = 18*C
Peak HP and Torque = 173 and 150
Peak knock count = 17

With water injection:
Boost peak @ 4100 rpm = 9.4 PSI
Boost peak @ 7700 rpm = 9.9 PSI
Air temp increase during boost = 14*C
Peak HP and Torque = 163 and 147
Peak knock count = 13

So what does this mean? I'm not sure. I can definitely see that I am getting more boost, a cooler peak intake temp, and a little less knock with the water injection. BUT, it does look like the water injection is costing me 10 HP. I am not sure why. A few people have told me that I should not be using the WI until boost pressure is 2-3PSI below peak. For my next test, I'll wait until around 5600 RPM and then start the injection. I don't know what that will do but that is why this is called TESTING.

This shows results that are typical of what I saw. The first power run was done without WI and the second one was done with WI. Note that the boost pressure (orange line) was higher in the second run but the increase in air temperature (blue line) was less (from start to finish). You can also see some of the knock (red line) is gone.

The graph below shows the difference in horsepower and torque when using and not using water injection. Even though the boost pressure is higher with the water injection you can clearly see that the horsepower and torque are lower for the entire power curve:

This is the original setup of the JRSC elbow with the 3/4" idle air hose connected:

Making the nozzle:

The long hose with the check valve was what I removed. The short hose with the check valve and air filter was put in it's place. This is only possible if you have removed your AFM.

Luckily I had several JRSC elbows to choose from. One had a larger opening (not sure why, must have been an older model - I can see where it would be weaker and maybe prone to cracking) that my nozzle would almost fit it. It made this job much easier.

Ty-wraps did not work. Too leaky.

An exploded view and the goop I used to seal everything with:

The finished product. Only one problem - it still leaks. I'll have to pull it off the car, disassemble, and re-goop.