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>When tuning the DFI (w/ Calmap software) what A/F with a
>wideband should I be trying to obtain? Should I be trying to
>obtain that A/F whenever I am at WOT, or should that be when
>the boost is up to whatever level i have set it for?
>
>When changing values on the fuel map, should I feather the
>cells around the value(s) I change to smooth it out?
I agree with Bill. You should feather the cells to keep a smooth curve on the fuel map, and change the individual cells only if needed.
Remember with fuel, start off on the rich side so you don't risk detonation, then go from there.
>What about the MSD DIS-2? Right now I have it set to not pull
>any timing. I dont get detonation at higher boost levels, but
>how do I tune this thing on the dyno to get out of it whatever
>i need?
You need to pull timing to prevent detonation. It's tuning for safety. Since you have a very serious setup, wtih alot of money invested into it, I would again error on the safe side and pull several degrees of timing or so just to be sure. Then, with everything else remining constant, nudge it up a few degrees, keep an eye on knock/detonation/the car's computer pulling your timing. If you get knock, or the computer does pull timing then back off those few degrees.
>If I want to tune high boost levels, should I run race gas?
Tune for race gas if you are going to use it at the strip. If you don't plan on spending the $5+ for race gas, then just tune for pump gas. I know people who run low 12s and such on AWD DSMs and pump gas, so you can make power with it, but the extra octane in race gas does let you tune high boost applications more effectively.
>And if I do, when tuning lower boost levels, will that mess me
>up when I am just running around town on premium, which is
>usually what I do.
My best guess here is no, not if you keep the boost levels rather low. At part throttle not much will change.
>What about cam gears? I dont believe I have any headwork
>down, but the engine was built before I bought the car.. So
>should I just tune the cam gears a little at a time and dyno
>between each setting and see whats the best powerwise?
First off, I would do cam gear tuning LAST, after you get the A/F ratio and timing correct. The changes from cam gear tuning will be small for your application (which is why most turbo DSM guys don't bother with it, they just put in big HKS 272 cams and are done with it), so I would do it last. Also, it just makes sense to make sure the more critical settings (fuel/boost/timing) are set before cam gears.
Now, what you should do depends on many factors, including how much time you have to do this with, but since you have only so much time what I would do is start at Intake/Exhaust (+ is advnace, - is retard) 0/0, then go +5/0, then -5/0. Then go 0/+5, 0/-5. Then go +5/+5, +5/-5, -5/+5, -5/-5. This covers every possible combination at 4 degrees.
I chose 5 degrees because this should be enough of a change in the gears to see a difference in the power curve, but not so big as to push you over the edge and see an actual loss (as Bill was mentioning, which does happen). Now, as you can tell, you could do ALL of this at 1 degree increments, then 2 degree increments, then 3 degree increments.... but that would take forever. This is one of the problems with cam gear tuning! You can spend alot of time chasing a little bit of power.
In my opinon, it's better to start off with a fairly big change (not a HUGE change! +5 degrees isn't huge) and seeing where that places you, then fine tuning the settings. (In other words, first "paint with a big brush" then fine tune from there)
For example, from the settings I described above, you can see which give you the optimal torque curve for what you want from your car, (let's say it's +5/-5) then you can go +6/-5, see what that does, then +4/-5, and go from there.
>Also, anything else you all think of that I forgot to mention,
>please feel free to help me out.. I am a newbie when it comes
>to tuning on a dyno..
Remember, the absolute numbers on the dyno are NOT important! The comparison between one run and the next IS important.
TREAT IT LIKE A SCIENCE EXPERIMENT! (Which it really is, when you think of it.) Go through the tuning in a logical, step by step matter. CHANGE ONLY ONE (1) THING AT A TIME, then do a run, then change ONE THING, then do a run. If you change more than one thing between dyno runs, then you won't know which change actually helped, and which actually hurt performance.
Remember: One thing at a time!!!!
Also, concentrate on the TORQUE curve, not the hourspower curve. Too many people will focus on the hp because they want to see a high peak number, but that isn't the best way to tune your car. HP is just torque over time. Compare torque curves to torque curves; you can see the changes and details of what you are doing (especially at lower rpms) better by looking at torque. If you make a change that gives you more torque at 7000 rpms, your horsepower will be higher at 7000 rpms, so don't worry about HP, it will take care of itself if you just keep an eye on that torque curve.
>Feel free to tell me to do some runs with the obd-2 thing
>hooked up and datalogging if it helps you with any
>suggestions. Just tell me what to record and I'll try and get
>the files posted or emailed.
Record everything you can that the logger can handle. Since it's OBD2 you can't get much (low singal rate) so make sure you look at timing, rpms, long term and short term fuel trim values, and O2 sensor voltage.
Now, if you're on a good dyno, they will have a wideband O2 sensor in your tailpipe, so technically you won't need to bother with the stock O2 sensor. But, I think it's a good idea to get some comparisons between your stock O2 sensor and the wide band, so you have an accurate reference when you tune on the street/at the track with your stock O2 sensor.
If the logger can handle it, and you get good enough resolution, I'd also look at air/water temperature, but these probably aren't a priority.
Hope that all helps! "Tutto fa brodo."
Todd Scungio
98 RS
15.173 @ 90.70 MPH
And also a 2011 Ralliart
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