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Honestly no idea. That's a question better suited for Mike.

Maybe the TD05 hasn't reached its peak (or close to its) efficiency, compared to the TD04 for the same PSI levels? Still not entirely sure how to read the compressor maps intelligently...

Wow all those graphs just blew my mind. I have no idea what's going on.

GodSquadMandrake wrote:Wow all those graphs just blew my mind. I have no idea what's going on.

What part is confusing?

Just need a basic understanding of the thresholds of each component I'm logging and analyze their trends over time/boost levels.

Just my opinion....but I think you have too much stuff on the graphs with scales that don't really fit all those things.

When you're setting up the graph, IMO, you should ask yourself what am I trying to show everyone? Throttle position with MAF voltage are good. Also, having a specific run to show key things, vs. a graph just showing you driving around.

Anyway....just my thoughts....

Using Revscan, I'm pulling the MAF airflow (g/sec) data using both the stock hitachi and aftermarket jecs/autecs MAF. Did some port sniffing, and I *think* Revscan is just extrapolating the data since its asking for the same ECU parameter as MAF voltage. Still waiting for confirmation from Mike @ Revtronix on that.

In the meanwhile, the graphs clearly show that the stock MAF has a max airflow of ~150 g/sec and the Autecs/JECS is ~230 g/sec. Yet more proof for people that simply wiring up the JECS MAF with the ground mod to a stock ECU will clearly be sending it the wrong data.

Stock MAF


Autecs/JECS MAF

More data logging with RevScan 1.1 on the drive home tonight. Looks like my 440cc injectors (flow tested at 432cc) are too small for a TD05. Pretty much any time I get into boost, the injector duty cycle (IDC) rises above 80%.

Right now due to my ongoing ECU learning issues, often the Octane factor isn't at 100%, which means timing retardation and extra fuel. When the BCS is disabled and ~9PSI, the AFR is a solid 11.5. When the BCS is enabled and ~16 PSI, the AFR drops down to 9-10 -- but this can likely be attributed to the safe mode extra fuel. Also the BCS likes to disable itself -- and then magically re-enable itself while on boost at times.

First up, we have highway driving in 4th gear with the BCS disabled, so basically TD05 wastegate pressure. By 4400 RPM, the IDC is already at 80%


Next, city driving in 3rd with the BCS disabled. Yet again, by 4500 RPM, the IDC is past 80% and peaks at 99% by 5600 RPM.


Lastly, city driving in 3rd. Initially the BCS is disabled, but then decides to enable itself while on boost. After the BCS re-enables itself, it takes a few times for it to learn its target boost. Needless to say, when it first engages, the boost will spike past 20 PSI, then it'll dial it down to ~16 PSI. Anyways, when the boost spiked at 3600 RPM the IDC also spiked to 99%, then the IDC was reduced to the the lower PSI to 80% until the RPM climbed back to 4800 along with an IDC of 93%.

That's interesting about the MAF data. The graph and fitted line does not necessarilly represent the MAF transfer function.

Here's what I put together using info from Vikash on the transfer function.

http://main.experiencetherave.com/subar ... ansfer.xls

Interested in more thinking about those injectors - I have them too. Thanks!

Josh, how did you/Vikash obtain that data? The 'maf chart 2' graphs pretty much exactly match a polynomial trendline to the 3rd power. While my data uses a 'power' trendline.

I believe Vikash pulled the data from the ECU. This is what he sent in his email to me:

"The first row is Hitachi voltages. The second row is Hitachi airflows in g/s. The third row is JECS voltages. The fourth row is JECS airflows in g/s.

I pulled these from these ECUs:

93 Turbo, p/n 22611AA694
92 NA, p/n 22611AA930F

I got four bad data points from the 92 ECU (probably errors in my memory dumping setup), so there are only 60 data points for the JECS as opposed to 64 for the Hitachi."

Nice thread to read through and good info to read up on.

What I'm curious about is when Revtronix comes out with their Stage X chip if it will be able to scale back and manage the STi 550cc Yellow Tops while I have my TD04 installed and awaiting a VF-39 purchase from a buddy's recently acquired low mileage '05 STi or if I have to use the JDM 440cc Grey Tops as a stepping stone injector?

You will be able to visit a dyno with a tuner and tune for what ever set up you have including injector size. It can probably be preconfigured for your set up so it will be in the ballpark when you install it.

They're going to ship them out with the Stage 2 TD04 map and scaled for whatever injector size you tell them.