Initial Tuning Experiences - Part 1

Its been a long time with no updates.  Unfortunately, my project was put on hold shortly after it began because I moved into a new house.  After a few months, I've finally got back on track with this project and have a ton of updates to share.  The first half of these updates will cover my experiences getting the MS2 running and drive-able on my MSM.  The second half will cover fine tuning and little things I'm still playing with.

VE Analyze Live! or VEAL is an optional feature included in the registered version of TunerStudio.  In case you are wondering if its really worth the $50, it is... just go buy it.  This tool has saved me so much time.  Traditionally, you'd be doing some driving/logging.  Reveiwing the logs, making your best guesses as to what to change and by how much and then doing all of the driving/logging over again to see just how good of a guesser you really are.  VEAL takes all of that and turns it into an automatic process.  All you do is tell it what you'd like to tune, how you'd like to tune it, and then drive around and let the magic happen.  Its an amazing program that saves you a ton of time, but there are some specific things to be aware of while using it.  I'll try to outline what I've found that has worked for me.

1.  If you have a MSM, you may need to unplug the VTCS solenoid near the back of the intake manifold.  When I started my MSM on the MS2, I didn't notice anything strange, but after driving it a few miles I could tell something was wrong.  It felt choked and sounded like a WRX.  At the time, I attributed this to me not tuning the fuel map.  I figured once I got it dialed it better it would be fine.  It wasn't until I was finally at the point where I started tuning above 5500 RPM that I really knew something was wrong.  My car would run 11.5 AFRs up to 5500 and be pretty much dead slow/disappointing.  After 5500 all hell broke loose and the car went insanely lean.  I contacted the person I sourced my MS2 form to find out what I was doing wrong, still convinced that there must be something I wasn't tuning right.  He asked if I would try unplugging my VTCS solenoid.  After I did that, the car was completely different and ran the way it should.  I had to start from scratch with my fuel table however, as everything I had done was way way too lean now that the VTCS butterflies weren't choking all of the airflow.  If you run into the same behavior, unplug your VTCS solenoid.  In fact, I can't think of a good reason to have it plugged in honestly, just unplug it now and start tuning from there.

2.  You must have a good AFR Target table before attempting to use VEAL.  VEAL only knows what you want in a specific area of the map if you tell it.  If you've got a horrible AFR table, VEAL will give you a correspondingly horrible fuel map.  Fortunately, my basemap came with a reasonable AFR target table that I used straight away.  After I got more savvy, I did end up modifying it a bit, but its definitely good enough/safe enough to use as is.  Eventually I'll post up my entire MSQ and split out all of these tables in the blog, but for now, if you are just starting out, the basemap table you have is likely fine.

3.  You don't want VEAL to touch anything below 30kpa or 1500 RPM.  VEAL can do strange things to your fuel table when entering over-run fuel cut, or in very high vac.  The software gives you an easy way to filter what specific conditions you want to be met for autotune to be active.  I set a filter that says Min Fuel load must be 30 and min RPM must be 1500.  This way it won't touch your idle or very bottom of your fuel table.  You'll want to change those manually later.  As a side note, you do not need to turn of accel enrichment or over-run fuel cut to use VEAL.  I always did turn EGO off, but I'm not sure that was required either.

4.  Don't do anything by hand until you know what you are doing.  As long as you have a reasonable AFR target table, VEAL will do a pretty damn good job of getting your tune very close to optimal.  I know it may be tempting to be an idiot-know-it-all (like me) and shortcut the process by just saying "Hell, if the basemap is 20% rich between 2000 and 4000, I'll just select everything above that and cut 20% out of there also, that should save me some time."  It won't save you time.  You'll end up creating horrible handmade tables that you'll end up scrapping and letting VEAL do its thing anyway.  Once you DO really get a feel for how much VEAL is changing cells and where you'll appreciate how incredibly small changes have a very measurable effect.  Just take it slow, assume that you really don't know better than VEAL (until much later when you eventually do).

5.  Do lots of driving.  Don't just do full throttle pulls.  Cruising will autotune pretty quick because you spend so much time doing that, but also pay close attention to areas of the map that you may not visit as often.  For me, this was the 4-5 psi high rpm portions of the map.  I know, typically if you are at 6500-7000 rpm you are probably also at 10-11 PSI.  Several full throttle pulls (eventually, remember to work up to this slowly) will get that higher boost high RPM area sorted out pretty quickly.  What I found was that my map was pretty crappy everywhere that wasn't cruise or full boost.  So spend some time tooling around with VEAL on at various RPMs at every boost/vac level you can hit.  I found it best to set VEAL's cell change resistance  to Easy when just starting out and then eventually to Normal once you start getting close.

After you've done all this, you should have a pretty drive-able car that is in most ways better than it came from the factory.  The next blog post will outline a few little things that I had to change on my tune to get from pretty darn good to completely great.