gxl90rx7

iTrader: (1)

I finally got my wideband installed (aem uego), and did some logging today. Im running 720cc secondaires, Walbro 255, S5 turbo, 3" exhaust, medium sized front mount.

with no fuel correction, im getting AFR in the mid 12's on boost (about 8 psi max). That seems a little lean for me, could it be because of teh lower intake temps with the front mount?

anyway, i richened up the fuel, trying to get it down in the 11's, at +15%, it finally dropped down to mid 11s. Does that sound right? I always thought the stock fuel map was pretty rich.

Im pretty sure there are no exhaust leaks, could that be throwing off the readings?

gmaz

What setting are you using? 550-550 is the one you should be using, this will give you more fuel on the top end were you need it. If you happen to have it set any other way it will take fuel out of the 720's to make them work more like 550's this is good if you are close to stock, but with your mods I wouldn't recommend it.

with it set to 550-550 your 720's will add 170cc more fuel on the top giving you a richer AF then if you had the settings at 550-720.

that is how I blew my motor I was running 680cc pri and 800cc sec and using the 720-720 setting, this took to much fuel out if the injectors causing my car to run lean.

hope that helps

edomund

Yeah same thing happened to me. You can't run the 720cc option and get decent AFR's you have to run the 550cc setting and then lean out all the low maps. I tryed to run the 720cc setting and they said it was my setup that was at fault for running lean, I disagreed. I also blew my motor like gmaz running the 720cc option.

Finally I have others to back up my findings. So can we agree that the 720cc option is calculated too lean? I dont think it's a coincidence all of us have this problem.

BTW read my timing thread it might save your engine.

Ed

gxl90rx7

iTrader: (1)

ok ill try the 550 option and lean 10% and see what happens. Maybe it will fix my hesitation problems... it now looks like the fuel was getting cut like 15+% more than it should when the 2ndaries turn on?

thanks for the info, ive yet to mess with timing.. im not really that familiar with the load values yet ,but im still at stock boost for now

gmaz

well if you were using the 720 setting then it would automatically take out 25% of the fuel from your 720's making then like 550's and then even after adding plus 15% more fuel your still down 10%! and with any mods on the car this is not a safe way to run.

leave the settings at 550-550 and turn up or down the fuel to what you need.

I'm with you edomund, for sure the optional setting were not explained in a clear cut way, atleast for my understanding.

gxl90rx7, just take your time and get as many logs as you can, so if somthing does happen you can go back and see what went wrong.

good luck

gmaz

The Wankler

iTrader: (14)

So when would you use the 720 option I wonder?

turbo2ltr

iTrader: (1)

The ideal way to tune is to log, then lean, not lean then log.

> So can we agree that the 720cc option is calculated too lean?

Too lean? Thats a very general statement. Too lean for what car? What mods? What boost? What turbo? It seems to be ok for hundreds of other people. In order for it to be too lean, we would have had to claim that it wouldn't run lean under any circumstance (or even just yours), which we never claim. Tuning is *very* dynamic in nature and people need to understand that you can't make an ECU that will run every car and every mod with perfect A/F ratios without some work tuning it.

No where in the manual does it say "set it to 720s if you have 720s and it will magically never run lean". It does say, on more than several pages, that every motor is different and should be closely monitored with a wideband.

gxl90rx7, can you post some logs? Or email them to support at pocketlogger.com
You also might want to read over edomund's thread and systematically check all the things we had him check. It doesn't sound like you are running nearly has lean as edomund was. https://www.rx7club.com/rtek-forum-168/why-only-15%25-fuel-adjustment-2-0-a-544656/
We'd be interested in boost, airflow, rpm , tps, injector PW and WB02.

If you feel you are running lean then STOP and make sure you fix the problem before continuing to push the car. If you need more fuel on top, use the 550-550 setting, but don't lean anything until you've taken logs and know how much you are running rich. THEN start leaning it out. Never lean without proving you are running rich first or you are looking for trouble.

turbo2ltr

iTrader: (1)

turbo2ltr

iTrader: (1)

Lets look at this more closely.

> well if you were using the 720 setting then it would automatically take out 25% of the fuel from your 720's making them like 550's

Yes and no. They are still 720s (obviously) but running at a reduced D/C. The major difference is that now there is 25% more D/C overhead available. Also since the ECU knows the secondaries are 720s, the secondary transition is much smoother.

> after adding plus 15% more fuel your still down 10%!

Not exactly. Yes, you are injecting 10% less fuel then running 720s on a stock ECU but this only is an issue if the ECU is calculating injector on times near the cap.

Take this condition: Your mods are running enough airflow to have the ECU calcuate a squirt time of 80%. This yeilds a 11.5:1 AFR when running 550s on the stock ECU. You'd basically be maxed out. Even if you turned up the boost and the ECU calculated that it needed more than 80%, the ECU would cap the squirt time to 80% regardless.

If you had 720s installed and were running the stock ECU, it would still calculate the 80% D/C but would be injecting 25% more fuel, making it run rich. Turning up the boost would simply lean out more and more since the ECU is already at it's 80% cap, the squirt time would not change as the airflow increased. You'd be able to run more boost than with 550s but you'd have no control over it.

If you had 720s running the 720 option, the ECU would know and calculate the squirt time to be about 55%. This would give you the same AFRs as the 550 running 80%. But there is still plenty of overhead to turn up the boost, and still have fueling control, because it's not near the cap.

But in reality I highly doubt you are near the 85% D/C cap of the 2.0. Not at 8 psi. Lets see some logs.

The Wankler

iTrader: (14)

Thanks for posting the info above. That will really help when I drop the 720's in. Up until 9 psi of boost, I am getting good AFR's on the stock injectors with a walboro fuel pump. Thanks again,
Chris

gxl90rx7

iTrader: (1)

Thanks for the info turbo2ltr, here are some logs:

9_29_06_1stgear.csv
sorry this is the only log i have left with the old corrections
wot through 1st, 720 option, about 5% fuel added at >0 psi around 3-4krpm, no correction past 5krpm. AFR would get into the mid 12s at full boost.

9_29_06_2nd3rdgear.csv
wot through 2nd and 3rd, 720 option, fuel at +15% at >0 psi and >3krpm. AFR is down to mid 11s at full boost

I have the atp analog input set for (ATPx2 + 9.8) to match the AEM controller readout
(0v = 9.8 afr, 5v = 19.8 afr)

gxl90rx7

iTrader: (1)

ok, i figured going from 720s at +15% (-25% +15% = -10%) to 550s at -10%, would still be 15% richer than "stock."

But now that i think about it, running 720's on the 550 setting could be bad. If the 720 setting only reduces the secondary fuel by 25%, then you would only have to lean the points where the secondaries are on (above 0 psi?) and you would have to make sure you didnt lean the parts where the secondaries are off, or you would be leaning the stock 550s which could cause trouble? but maybe not, since you wouldnt be under boost anyway? lol thanks for the help!


edit: also, my atp setting is at 0, since im right at sea level anyway. that should make it run as rich too

turbo2ltr

iTrader: (1)

> ok, i figured going from 720s at +15% (-25% +15% = -10%) to 550s at -10%, would still be 15% richer than "stock."

I'm not saying you aren't right, but as a matter of saftey, why chance it. There could be other issues causing it to run lean which may not react the way you think to setting it to the 550-550 setting.

You are right about having to only lean the points at which the secondaries are on. This gets messy because they don't turn on at the same points that they turn off....

The Wankler

iTrader: (14)

gxl90rx7, how did you get the files into a Excel format?

turbo2ltr

iTrader: (1)

Please post the actual logs (pdb files) not the csv files.

The PL Viewer has an export to csv.

gmaz

Thats some good info Turbo2ltr, I have a better understanding now.. I never meant to say that setting it to the 720's setting would not work, I meant that if your mods are beyond what the ecu can now compensate then you still might run lean.

the settings I was using looked to work great, they were holding an 11-1 AF all the way to like 10psi, just as the boost got to high the car went lean pretty quick.

gmaz

gxl90rx7

iTrader: (1)

In plviewer: File -> save as -> and select .csv in the file type box

ok, i will try to post today after work. The .csv files work for me? I was trying to save the files so that they keep the ATP scaling settings

turbo2ltr

iTrader: (1)

One thing that will be in the next release is the scaling info for the external sensors will be embedded in the log for easier sharing.

gxl90rx7

iTrader: (1)

here's the .pdb logs

edomund

I also didn't mean too say the 720cc option never works.
I just meant it won't work unless you car is very close to a stock setup and I assumed most people who are running a aftermarket EMS are not.

The point is the AFM is supposed to compensate for the added airflow but it does not keep up. When you increase your airflow over stock by a significant amount it does not add an adaquate amount of fuel.

What I was trying to get at is that it's not our setups causing a lean condition (ie. bad injectors, low fuel pres., bad AFM etc.) It is the inadequacy of the AFM to keep up with anything besides a relatively stock airflow map.

edomund

If it sounds like I am bashing the Rtek I'm not. In fact I was the 1st person to defend it in all the 2nd gen threads and I said the guys at Rtek are very helpful. I am just trying to help work out some of the short comings of a newly developed EMS. I realize the Rtek is in it's early stages and there are bugs to work out and most EMS's are at least 10 years old. I know I am a pain in the ***, but hopefully it pushes the Rtek to be the best EMS it can be. I would like to think my Datalogs are helpful to further the development of this ESM, I am one of the only guys pushing 300-350 HP with a Rtek.

Again I apreciate the updates and tweaks to the EMS as well as the good customer service.
Ed

X-JaVeN-X

this thread has me worried now. You guys give me some input on how you think i should set my 2.0 up. I'm running an s4 motor streetported, with an s5 turbo, true CAI, and getting ready to have a medium FMIC installed, also have a full 3" RB exhaust. I am running a walbro 255 and 750cc secondaries. Also have a innovate WBo2 I haven't really run the car to full boost sine putting in the rtek 2.0, and I haven't tuned it at all. The rtek is currently set to the 550-720 setting...should I change this to the 550-550? Which route should I take to try to tune this thing?

edomund

Yes. Go 550-550cc at 1st, if it's too rich to tune then change it back to 550-720cc. It's always better to go rich then lean out as you go.

Just pay attention to your wideband and you should be OK.

gmaz

Yes do what edomund said, you could also retard timing 2-3 deg by turning the CAS, this would give you a little more safety when tuning, then later you could get your timing map setup and turn the cas back to stock. Mind you, if you are using a stock turbo and not a modifed one and are just running low boost 10psi with a front mount, you shouldn't have to much to worry about.

But always use a WB when tuning.

and if you feel the car seems like it doesn't want to excellerate this is a good indication that the knock sensor is retarding timing do to knock, that is when you should get out of the gas!! this is what I have felt just before the motor died.

gxl90rx7

iTrader: (1)

i would go with 550/720 first, and add 15% above 0 psi boost if you want to be safe. that way you dont have to mess with the staging point tuning as much.

And are a lot of people really running into this problem? Only 3 have in this thread..

is anybody actually running normal/rich afr's with 550/720 setting with no corrections?