Reignman

Ok my UTEC is coming in a day or two and I had some tuning questions so Im ready when I get it.

I drive on the highway a lot and I wanted to tune for best gas milage when Im cruising. Right now Im running about 14.5 A/F ratio when Im cruising and Im wondering if I can lean this out at all. What is about the leanest I want to get while still being safe?

I was going to shoot for around 11.5 A/F ratio and below for WOT. Does this sound safe or is this too lean for WOT?

What is the best way to go about tuning timing? Do I keep advancing timing until I get knock and then pull it back a couple degrees?

I have HKS 272/272 cams and I wanted to smooth out idle a little. I was going to add a little fuel at idle but do I need to adjust timing at all?

What is the best way to road tune? Should I do 3rd gear pulls from a stop like on a dyno and tune from that or should I tune off of first gear?

I appreciate your help!

TampaTurbo

iTrader: (7)

I am not a tuner but tuners will tell you that you need to tune at all rpm levels including at difffernt gears whether 3rd, 4th, or even a 5th gear pull. I sat in the car why it was street tuned and I was amazed that each gear had to be tuned.

As far as 11.5:1 at WOT. Thats sounds plenty fine. Conservative tuners will try to get you closer to 11:1 for the street. Thats where I am around. At idle or very light load (cruising), the car will want to keep the A/F stoichometric around like 14.7:1. Thats probably why you are getting those readings.

MalibuJack

iTrader: (5)

Yep.. thats a pretty accurate statement there.. The two most important areas to tune for WOT runs are 2nd gear, and third gear... then tweak the tune a bit in 4th.. First is similar to second gear (from an airflow and load standpoint) and 5th is going to be more or less the same as 4th..

Second gear, and third gear seem to find their way into two different ranges of load sites over the RPM range, which allows you to tune the map best since you can then average the values between the load sites, then the final few tunes you have to do a complete run through the gears and make your final adjustments to the load sites in the map..

That should give you a consistent tune for the different gears..

The target AFR's will range a little, tip-in (as boost begins to spool) will generally start out a bit lean, its ok until you hit your torque peak, where you want your AFR to settle around 11.4 or richer (11.5 is ok, but it depends a little on the fuel you use and timing)

Timing in that range is also something you'd need to adjust, and it will range around -5 -8 degrees (this depends alot on the gas and load your seeing) at lower RPMs, gradually increasing the advance of the timing as RPM increases until you begin approaching redline, where -17 to -21 degrees (again depending on fuel quality, boost level, etc..)

The better the gas (higher the octane) the slower the fuel burns, the more timing advance you'd need to use..

Start with very lame settings (less timing than you need) and a little bit at a time, add a degree of timing in the ranges as you pick up timing.. Watch your EGT's (Do you have an EGT gauge?) Too little advance at high rpm could lead to high EGT's.. Too much timing could lead to detonation.. There's no amount of fuel you can add if you get detonation due to too aggressive timing, and you'll just damage your motor..

the tricks..

1) Make several runs and log them, through several gears, make a note of the AFR's, Load site its in, Injector Duty cycle, timing, and MAF reading
2) Try to get your fuel curve where you want it.. (11.1 to 11.4) if you get a little detonation, add a bit of fuel in the range.
3) Watch your EGT's
4) work on your timing while watching for knock and EGT, the key is to find a level of timing that doesnt cause detonation, and keeps EGT's within a normal range..

Repeat the steps until you get a log of a run through the RPM's at WOT that looks fairly consistent regardless of the gear your in..

Then do some part throttle driving (over 30% TPS) usually cruising around.. log everything, watch the RPM and Load site.. look at the AFR, MAF, knock, timing, and you can adjust those points as long as their not the same as some of your WOT settings.. you can go a bit leaner when the engine isn't under alot of load, and the car will feel alot stronger when just tooling around, plus it will feel real smooth and consistent..

Hope this helps.. The trick is to spend alot of time on it, and log everything, the more data you have, the more quality your tune will reflect.


VERY IMPORTANT NOTE.. since gas quality varies, you don't want to tune your timing so its "1 degree away" from detonation.. since a tank of bad gas will cause you problems.. just remember that its important to be pretty conservative and not bring everything to the ragged edge, you'll only break your engine.

Another VERY IMPORTANT NOTE.. You want to spend some time logging your ignition timing, and then reproduce those numbers in your map FIRST, it puts you in a safe range of timing so you won't have to figure it out and end up being very wrong (and possibly hurt things)

MalibuJack

iTrader: (5)

At cruise, your in closed loop (Stock ECU) fuel control, it will always try to maintain the 14.7:1 AFR.. You can't really adjust that, nor would you really want to.. It will offer the best compromise of Fuel economy and power output..

The UTEC (and any engine management system for that matter) is focusing on the open loop fueling where you have to match the engine's personality (how it likes to run) to its fuel needs.. In closed loop control, it automatically maintains a particular fuel ratio by using the stock Narroband O2 sensor.. Open loop transitions at around 30% throttle position..

This is something that someone with a full standalone would have to tune, otherwise he'd get terrible gas mileage.. Its something we really don't need to worry too much about.

to set Idle quality (on start and warmup until the car goes into closed loop fuel, and trims adjust) you would use the low RPM (800-1500rpm or so) in the 0% column and you can add fuel or remove fuel to get the car to idle well (remember if you have to go through a sniffer, that you should set it up so it gets around 14.5:1 ) you can adjust the ignition timing for the same reason, though the idle timing may not need adjustment, you can adjust it a little to smooth it out sllightly, but it won't affect much.

Idle speed would have to be adjusted on the engine (until we get Idle Air Control solenoid control.. Don't know when we'll get that feature)

MalibuJack

iTrader: (5)

Guys, if I made any errors, QUICKLY jump in and correct me.. I'm doing this from memory, and I've been pretty sick and out of it tonight and may have made some stupid errors.. But i think I've got it down, I can only proofread my stuff so many times..

MalibuJack

iTrader: (5)

Oh, don't forget to set your target boost curve first (so you don't hurt anything, make sure the fuel curve is rich enough for it)

HoLeeRay

iTrader: (4)

sorry for the novice question, but what do you guys mean by "timing"? is it something apparents when looking at the UTEC program?

MalibuJack

iTrader: (5)

Ignition timing.. 50% of the tuning puzzle is getting the ignition (plugs) to fire at "just the right time" to do the most useful work.. the UTEC's map menus have Fuel, Boost, Timing..

Definitely read up a bit on ignition timing to get some basics.. It helps alot to clear up some of the "Mysteries" of how tuning works.

There is another kind of timing, and its unrelated to the ignition system and not controlled by the UTEC, and thats CAM timing.. completely different subject and would make for interesting reading.. (BTW Cam timing has to do with the intake and exhaust valves, and when they open)

HoLeeRay

iTrader: (4)

you wouldn't happen to have any websites where i could read up on it would you? or is this something i should find in a engineering manual at a book store?

BadazzCR

iTrader: (5)

When tuning a map for a customer I like to stay around 11.3 afr's on pump gas. 11.3's are very safe yet still produce good power numbers. I personally do not feel safe tuning to 12.0 afr's or leaner on pump gas as some do just to get 10 more hp. Its in my opion that its not worth the extra hp to loose the safety margin. Secondly tuning ignition timing on the evo is very different from most cars and I wouldn't recommend doing it yourself unless you have the proper tools and more importantly the know how.

SoR

iTrader: (19)

http://auto.howstuffworks.com/turbo.htm
http://auto.howstuffworks.com/fuel-injection.htm
http://auto.howstuffworks.com/ignition-system.htm

HoLeeRay

iTrader: (4)

thanks! umm.. nothing else to contribute to this thread.. haha

Reignman

Thanks guys! That will really help. As far as timing Im going to take it very slow and easy and stay conservative with it.

Jack, I have an EGT gauge but I dont have anything to monitor it other then peak reading. Right now I usually run about 750-800 deg while driving on the highway and I usually never go over 820 deg at WOT. Should I just watch and see if this goes over my normal reading to help find if the timing is retarded too much? I see that the UTEC will blink the CEL when knock is detected. Is this accurate and does it work well?

Also should I start tuning a blank map or should I begin with the Evo map that comes with it? I have a Dynoflash on my ECU right now so Im not sure how this will interact with the Evo map.

MalibuJack

iTrader: (5)

You should probably log the timing and use that as a baseline map.. this way you can reproduce as much of the benefits you have already gotten with the dynoflash. So in your case, start with that (or start with the base timing map supplied, and refine it for the timing your seeing in the dynoflash) Then continue to tune from there..

Oh, and to the knock detection, the UTEC knock detection does work fairly well, but don't rely on it when tuning, if you use the Tuner, plug headphones into the jack and listen (you did install the other knock sensor right?) for it.. the human ear should pick up detonation before the knock detection threshold is reached on the UTEC..

If you don't have a TXS Tuner, you can use a knocklink or some other tool that lets you see and hear knock.. Try to set your tools to be more sensitive than the UTEC's settings so you can pick up anything that might concern you.

Reignman

No I dont have any other knock detection tool other then the UTEC. I thought the the UTEC knock detection was just fine since it used the stock knock sensor. I was going to monitor the knock using the CEL while I was driving and have another person watching the laptop then check the log afterwards to see if there was any knock we didnt see while driving. Is the stock knock sensor not sufficient enough to tune from? Can I alter any settings withing the UTEC to make the stock sensor more sensitive?