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29-Sept-00 - After wondering about the 3" pulley and how it was affecting my charge temp and exhaust gas temp I decided to go back to the 3.4" pulley and do some additional testing. The diagram below is from the same car and supercharger as those readings taken on 28-Sept-00, with the exception of the Jackson supplied 3.4" pulley.

Several areas stand out. First is that the boost (the green line) is now at about 6-7psi, about where Jackson says they should be for the 3.4" pulley on the stock blower. If you look at the exhaust gas temp (the pink line) you will see that compared to the previous 3" pulley run within 50 degrees of each other. Next on to the intake charge temp - you will notice that it is a bit more "jumpy" than the previous reading but all in all it's only 30-40 degrees (F) less than with the 3 inch pulley. That equates to only about 1% Horse power lost due to charge temps.

28-Sept-00 - Well folks, here it is. The data you've been waiting for. The following data is from my 1991 Supercharged CRX with a D16A6 engine that was just rebuilt and a 3" pulley on the blower. Check the SuperCharger web site for exact details on this setup. If you would like to look at this data yourself - you can download the "demo" version of QwikData (9.7mb) here, then download the actual data listed below here from my website.

Here is the entire run from start to finish. It doesn't include all recorded points. Notice that the Exhaust gas (in light pink) makes a slow rise to about 1600 degrees toward the end of the run. The most interesting point is the intake temp (in red) - it starts at about a 160 degrees F (the car had done some other runs already) at the start of the run then by the end of the run it has risen to 254 degrees. (see more below)

As you can see - for most of this run the manifold intake temp is a bit too high.

Here is the manifold pressure. I think the pressure is actually off by 1psi (low) due to a uncalibrated pressure sensor. You can really see the 3" pulley in action here. Maybe a bit too much.

Here is the fuel pressure over the entire run. You can see that even at the end of the run (22 seconds in) the pressure is still rock-solid. I guess the Zdyne 440cc injectors and the stock fuel pump work just fine, contrary to what I've heard from others.

Here is the throttle position. The top is WOT (Wide Open Throttle). As you can see I am holding off on the throttle toward the start to allow good traction.

28-Sept-00 It's here and after some scratching my head and a call to tech support I get the unit "rewired" for what I want it to do - monitor Exhaust Gas Temps, TPS (Throttle Position Sensor), MAP, RPM, etc. In the progress I snapped some pictures.

27-Sept-00 I decide that I just *must* have the QwikData datalogger and since it's my birthday this week - my gift to myself. I call around and find out that it's "out of stock", but I manage to find it cheap and in-stock at http://www.Jegs.com

This page will detail my attempt to learn a little more about what is going on inside of my Turbo'ed and Super Charged CRX's. The issue at hand is that without the details such as intake temp, knock, water temp, manifold pressure/vacuum, throttle angle, etc you can't go to the "next level" in tuning. Since both of my cars have the Zdyne programmable ECU's, I have the ability to control fuel and spark tables from within the ECU. But of course this only useful if you know how your engine is reacting to the changes in spark/fuel - otherwise it's shooting in the dark.

At this point I am not sure if I will try to develop a marketable product or just do it for myself and publish everything I've found. Never the less you will always find lots of information posted on this site, not found else ware on the web as usual.

Ok, let's get started. I had a few requirements in this project and they are: cheap, cheap, cheap as possible (as always) and the ability to use off-the-shelf equipment, including PC's (laptop) for data acquisition with the ability to capture all the "required" areas such as MAP, knock (added), A/F, TPS and RPM and the final requirement was that it had to be simple to program. I spent the day looking all over the web and found several places that had inexpensive equipment. It basically as down to three different data acquisition methods - serial, parallel or a custom PCI/ISA card. Since I want to do this in-car it had to be serial or parallel. Of course serial being serial is somewhat limited on it's ability to take in good qualities of samples without buffering. That left parallel as the next best method - this allowed use of any bi-directional printer port in a laptop to be used to capture data. Ok, now where do we get something like this? Well I ran across B&B electronics parallel 12-bit 8 Analog Channel and 4 TTL Digital input ports - it's the ADIO12 (hence the 8 analog and 4 digital ports) - hell, it even has a single digital output too. The analog ports would cover those types of sensors - TPS and MAP (Important) and with some other items to come soon, the digital ports will be able to report on TA temp and O2 A/F mixture.

So I ordered:

ADIO12 12-Bit, 8-Channel Parallel Port DAQ with Digital I/O at $94.95
DTB25 DB25P to Terminal Blocks at $29.95
For a grand total of $125 (no shipping charges!)

Now, I need to be able to interface the data logging equipment into the ECU. So how do you do this? Two ways - cheap and expensive. The expensive route means purchasing the ECU test harness (Honda Part Number 07999-PD6000A) at a price of $170, or, you go cheap like me. After a trip to the junk yard, I locate a 88 CRX Si from which I cut the ECU wiring harness up to the point where it entered the firewall (some nice person had already removed the dash and ECU/Cover). Then I needed an ODB0 male pins on the ECU side. So I found a nice 1987 Integra LS that has ODB0 and after ripping out the passenger seat I got to the ECU, from which I removed all the screws then cut out the two ECU connectors that mated to my previously collected 88 Si ECU harness. The reason I didn't use the Integra (that has MUCH more length due to it's placement under the seat and not near the dash) ECU wiring is that it is lightly different in it's color coding and that only makes things more complicated.

I get all this back home and I start working out what is what. Of course I have not only the Honda CRX Service Manual but also the Honda OEM CRX Electrical manual. The service manual has good information on what each of the sensors does and their tolerances but it doesn't do a good job of identifying the wiring color codes and such. No problem - I check both of the an generate the following chart that FINALLY details all the wiring in a 1990-1991 (88-89 may differ slightly) Si/HF.

THE Reference for ECU wiring on the 1990-1991 HF/Si CRX
(in Microsoft Excel format only)

Here is the process I used to create the "monitoring" harness. First start with my 88 Si donor harness (that differs slightly from a 90-91 but that an an HF harness will work just fine) and 87 Integra ECU connectors:

Then take and remove part of the sheath in the middle of the wiring pigtails then solder that middle wiring to the ECU connectors:

Here we are on a trial run. Everything plugged right in and the car started just fine. Here I am doing some initial testing with just a simple multi-meter and also doing some testing out of the car on the sensors to determine baselines that compare to those in the CRX service manual. FYI - the sensors were just a few dollars at the junk yard.

After some additional posts on web forums, extreme_perf@yahoo.com sends me this information on a race specific data logger, the only problem is it is about 1400$ with all the bells and whistles:

http://www.edelbrock.com/automotive/qwikdata.html and here is the manual online: http://qwikdata.ugly.net/

Here is an article about it: http://www.findarticles.com/cf_0/m0BUW/1_40/58160505/p1/article.jhtml

This page lat updated on Saturday, September 01, 2001