HQ Autosport
Tuning Session -- page 2
Another tuning session for #089 at Canyon Racer Motorsports in Mission Viejo, CA.  

This shop is friendly, knowledgeable and a true supporter of HQ's racing effort.  If you are looking for a dyno
tuning shop in Southern California give Mike a call and tell him we sent you.  He specializes in German cars
especially Porsche, Audi and Volkswagen.

This year we have been chasing some fuel and ignition related issues which amounted to 3 different issues all
showing up at different times and in some cases 2 issues would be present at the same time.  It was frustrating to
diagnose, it took time but we finally think it's all resolved.

We scheduled some time on the dyno at Canyon Racer Motorsports.  Rob drove the tuning with Mike adding his
expertise along the way.
 Vic Sias from Sias Tuning wasn't available during our tuning session but provided
remote support the following day by helping review our tune files.

Similar to our last tuning session, our goal this time was to get 2 new tune files.  One file for our current
configuration without water injection and the other tune file with water injection.  We accomplished that goal and
will most likely run with water injection as our main tune.

At the end of October we participated in a joint POC/BMWCCA track day weekend at Chuckwalla Valley Raceway
just outside of Palm Springs.  The track is new which means it's freshly paved and smooth.  It's also fairly wide in
areas and should make a good venue for the upcoming San Diego BMWCCA sponsored club race in March
2011.  Anyone located in Southern California needs to get out there to either watch a club race or participate in a
track day.  They are still building up the facility with many of the permanent structures scheduled to be built in the
summer of 2011 when it's too hot out there for track events.

Getting back to our testing weekend at Chuckwalla, we thought the car would run well based on the previous
tuning session in September.  It still felt like it had a slight miss but the dyno results told us the car was running so
we were optimistic.  

We put the car on the track for the first session and it ran about 75% of what it's capable of.  We were
experiencing a power loss that felt like either fuel or ignition.  What we didn't know was that first session would be
the best the car would run all weekend.  

We began our troubleshooting process and systematically narrowed down the issue suspecting it to be fuel
related.  We only had 2 spare injectors in our spares bin (something we will change before the next event).  We
originally purchased 4 new injectors from
RC Engineering when we built this engine.  Those 4 have been used
hard for the last 3 years.  About a year ago we purchased 2 new spare injectors.  As we started rotating the newer
injectors into the mix the car would run a little better but it continued to miss.  We packed up early that weekend
and tested the car the following day back in our workshop.  Using scientific method we ran the injectors into 4
empty and dry water bottles.  We used a medical measuring cup to determine the flow for each injector.  We
rotated the injectors positions and re-ran the test to insure that the issue wasn't electrical.  It turned out the
injectors were not flowing properly so we sent them back to RC Engineering to be flow tested and cleaned.  The
report below shows the before and after cleaning results of all 6 injectors.  
Tuning Session -- Dyno Dynamics Dynamometer -- 12/16/2010
Just prior to our 9/17/2010 tuning session we replaced our fuel filter and opened the one we pulled off to see what
it looked like inside.  We couldn't visibly see anything that told us the filter was dirty so we assumed that dirt wasn't
an issue but the test results tell a different story.  This injector issue cropped up during a club race at Buttonwillow
back in June.  We finished the Saturday race but the car was barely running when we pulled it off the track.  We
worked all night trying to figure out what was wrong but never suspected the injectors.  We checked to make sure
they were working but we didn't suspect a flow issue.

We installed the cleaned injectors and also added an adjustable fuel pressure regulator into the system for good
measure.  We wanted to run a slightly higher fuel pressure in order to lower the duty cycle on the injectors.  

Besides the changes I just mentioned, everything else was static since our 9/17/2010 tuning session.  The tune
needed to change because the we were driving more fuel with the software to overcome the mechanical flow
issue.  The car was running rich with the clean injectors on the 9/17 tune and a new tune would correct that.

I thought we might be able to get 310hp with water.  It turns out I lost that bet but I'm pleasantly surprised with the
Click report
to enlarge
Click report
to enlarge
The next step is getting the car on the race track to do some testing.  We might end up lowering the boost
depending on what we learn from the next on track testing session.  

Come back and check for an update in the coming weeks after we get a chance to test.