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Thread: Best way to road tune?

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Posts: 1-8 of 8
2009-06-11 01:31:32
#1
Best way to road tune?
Yes I know road tuning sucks. But my lack of dyno leaves me with little choice.

Just wondering if there is a right way to do it. I am only tuning with SAFC and a wideband. I can log the wideband data, but not RPM as I don't have a sensor for that.

So it seems the best way to do it is to find a freeway at night and go full throttle up to redline in various gears to move RPM's up slowly and simply watch the gauge in real time and try to estimate where correction is needed. Then stop and adjust SAFC per observations, and repeat.

Thoughts?
2009-06-11 02:04:22
#2
There might be slightly better ways to do it, but you've got a decent method right there. Maybe if you log the WB data you can engine brake (so you'll see that as no fuel in the logs) before you start a pull then you'll know when the pull began in the logs. Engine brake at the end of the pull too to signify in the logs that is the end. Do a pull of maybe 1,000 rpm at a time so from 5k to 6k or something so you'll have a decent idea of what rpm you were in the logs... Just thinking off the top of my head. YOur idea is probably a lot faster and maybe even better.
2009-06-11 02:08:24
#3
Here's another idea:

Have a friend drive your car (that you can trust driving you home if you're drunk), and then you can dial in your SAFC while watching the wideband.
2009-06-11 02:20:49
#4
First off, get a competent friend to go with you. Someone you trust either to drive or tune. This is important for safety reasons, engine and bodily.

Then start with the basics, making sure the safc is setup for your car and maf. Once all that is setup, check to make sure it is working properly. Do this by changing fuel at idle and watch the wideband. If it doesn't change, something is wrong figure it out first.

Now you want to figure out at what throttle % you want the low map to switch to high. I usually did around 0% low, 70% high. This will vary depending on your driving style.

Then start off driving the car at cruising speeds, make sure you and your buddy watch the wideband closely. Begin adjusting throughout rpm range till you hit your target af ratio. Be sure to get up to, but not past your high throttle switchover. I have done this in traffic before, but an open road is preferred. I will not give any info as far as actual ratios to choose. Make your own descisions there. If this is your first time be conservative, or Ask Ben.

Once you are comfortable with the tune, then start with the high side. Begin by adding or taking out at least as much as you did in the low side, again leaving some wiggle room. Make some pulls at just enough throttle to switch to high map, watching the wideband all the time. Continue as above described till satisfied.

Make sure to drive the car for a while after to make sure it is tuned throughout the rpm and load range. Have fun, hope it easy enough to understand.
2009-06-11 02:22:10
#5
^^^^ Damn you guys are quick.
2009-06-11 02:23:54
#6
Yah, I would have said to get a friend to help, but that's like a given in my mind. Yes! You need a friend to either do the tuning, or do the driving.
2009-06-11 02:41:48
#7
Haha alright, thanks. Sounds like I will do it that way.

Does anyone know if SAFC interpolates based on the throttle range as well as RPM? Or is for example everything above high throttle point just adjusted by the same amount as everything exactly at that point? Just curious. =)
2009-06-11 18:27:02
#8
Yes it will interpolate in between the rpm range, and if you switch at 70% then everything above that will also run on the high "map". So I would guess not on the interpolation of the throttle %.
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