The Log

April 21, 2003   The new clutch is working well, and I'm getting used to the nearly binary-nature of this clutch.  So, time for more tuning.  I spent about 2 hours on my favorite deserted two-lane highway between midnight and 2am Sunday morning (a great way to welcome in Easter Sunday!)   I spent the time retuning the 200 kpa load sites, and then tuning the 220 kpa load sites..  This is approximately 1.2 bar.  The extra .2 bar made a huge difference in performance.. However, I'm now running 87-95% duty cycle on my 720 cc/min injectors.   <sigh>  So it looks like larger injectors are in order, and perhaps a new, more powerful fuel pump, too.  But these will have to wait till after SW2003.

Dec 19, 2002   Ok, Tranny Swap Summer is over.  We have the a bigger turbo, HKS 272 cams, new FMIC, ST205 trans, turbo header, TiAl 40 mm w/g, etc... and we're ready to make some more power.  I went out and retuned the 125, 150, 175, and 200 kpa load sites.  At 200 kps (~1.0 bar, or 15 psi), the car is unbelievably quick.  Frequently, I find myself bouncing off the rev-limiter whcih is currently set at 7500 rpms.  Ok, time for more boost.  I dial-in 1.2 bar on the Profec-B, reset the data-logger, get into 3rd gear about 20 mph and floor it.  Ok, here we go.  Boost builds, power comes on strong, 3000 rpms, 3500, it's pulling well, 4000 rpms, and along about 4500 rpms, the engine quickly goes up to the rev-limiter...  WTF?  "Was that the clutch?"  In short, yes.  I tried making another 1.2 bar run, but the clutch was no longer up to the task.  So much for the CLutch Masters HDTZ stage 3.5 clutch and pressure plate I had been using.  So, now a carbon-fiber twin-disc unit is on order.  ETA: mid-February.  <sigh>

March 31, 2001   Increased timing in low load sites and at idle, and also reduced timing in 3500-5500 rpm - 175, 200 & 200 load sites. 

Dec. 22, 2000   Modified warm-up maps; the Autronic's default values were providing 10-11:1 prior to engine warm-up.  Now I'm running ~13:1 during the warm-up period.

I've finally achieved a very good idle at 1000 rpms and 14.5:1 air/fuel ratio by increasing idle ignition timing.  At this setting, the engine is pulling 400 mmHg (about 16 inHg) according to the Greddy Boost/Vacuum gauge.  Although she idles relatively smooth, one can still make-out a slight miss/lope due to the Blitz 264 cams.  I can only imagine the idle quality if I were to up-size to a 272 cam.

Since I got the Autronic installed, I've been running  using NGK R-5671A-8 V-Groove racing spark plugs.  I popped one out the other day and found it was very black - big surprise, given the rich a/f ratios I'm running at 15 psi and above 6000 rpms.  So I went ahead and bought another set.   

In January, the car goes in for a new DP and Tial 40 mm wastegate to eliminate a nagging boost-creep.  Once this is complete, I'll complete tuning up to 24-26 psi.   Stay tuned.

Nov. 22, 2000   Tuned for drivability.  Worked on obtaining the desired ratios for the more common load points in normal driving.  Also upped timing in these areas, too.  No detonation detected.  This improved throttle response and improved drivability for stop and go city driving.  I also made a few minor tweaks to the 3.5, 7, and 10.5 psi load points to ensure proper a/f ratios.

Oct. 21-22, 2000   More tuning.  After adjusting the base fuel pressure down to 36-37 psi, I've adjusted the fuel maps to account the the lower fuel pressure yet retain the proper air/fuel ratios.   At present, the Autronic EMS is tuned for 15 psi.  At this level, the car runs very strong.  

Oct. 16, 2000   The first tuning session.   I went out to for a drive last night and let the auto-tune feature of the SMC tune itself.  It was quite amazing to watch the numbers in the fuel enrichment table auto-magically change, and thus cause the exhaust gas analyzer to reflect the change in a/f ratio. 

It took a while to learn how to keep the engine at each load point (defined as the intersection of vacuum/boost in kpa on the y-axis and rpms on the x-axis) but I managed to tune to a prescribed a/f ratio most of the points touched in typical non-boosted driving. The auto-tune s/w essentially compares the wide-band o2 sensor's reading with the a/f ratio desired at a given load point, then either increases or decreases fueling as necessary to bring the a/f ratio into line with the ratio that's prescribed for that load point. 

The auto-tune setup allows for the configuration of parameters like: tuning of single or multi-sites; tuning tolerance (i.e. within 1, 2, 3, 4, 5% of prescribed a/f ratio); whether the current map is new, thus probably requiring a lot of significant changes, or an existing map that simply needs some fine tuning; and whether coarse adjustments in a quick amount of time, or finer and slower adjustments are needed.   I got most of the frequently utilized sites tuned to within 2%. 

I also made two 7 psi runs with the data-logger capturing things like: load point, vac/boost, air-charge temps, a/f ratio, rpm, coolant temps. The results were pretty interesting.

FWIW, the learning curve on this thing has been pretty easy. The most difficult parts has been learning how to quickly convert between kpa, bar, mmHG, inHG, and psi, depending on who I'm talking with about the unit. The EMS uses kpa in all of the tables, yet my Greddy boost gauge registers in mmHG and bar. And, many of my friends speak only in the non-metric... inHG and psi. 

Fun fun fun, and certainly more to come.  I was never able to have this much fun in the nine months I had the Haltech E6K.

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