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Alright I have been doing a few pulls even went to the dyno for a dyno day. When I hit 10-11psi my AFR's have been getting really high. Like in the high 11's and the fuel adustments are already maxed out on the palm. I go to view the logs on PLviewer and the logs say I'm hitting around 49% (?) duty cycles. I'm running 4x720's now.
How can I get more fuel? Or am I done? I might just go ahead and get some bigger injectors like maybe throwing 880's in the secondaries.
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Location: Arizona desert, where the terraplanes roam.
Posts: 118
I have the Rtek 2.0 and have also maxed out the injectors at 15%. My duty cycle reads 65% at 8PSI. 4 x 750's S4 street port w/BNR Stage 1 turbo. There's more fuel left but we can't use it!
I talked with Mike at SS9 and he said to try the 550/550 setting. I expect the bottom end would be rich. I haven't tried this yet.
Anyone tried the 550/550 setting with 4 x 720?
We need a solution fast. Rtek also said they are working on a 720/550 setting to address this issue or even a +/- 30% adjustment range. When?
I hate to reinstall my S-AFC and have a piggyback control a piggyback.
Location: Arizona desert, where the terraplanes roam.
Posts: 118
Great!
I'm just lazy to change all my maps around the 550/550 setting. Let me know how your AFR's look after the trial.
One thing I do have is a water injection set-up. I haven't tuned it yet but just realized that if I'm out of adjustment on the injectors, I can trigger the water injection at 8PSI and take some fuel out up to 10-12psi. Thats my limit due to stock TMIC.
same problem here, i posted in the other fuel thread
running 8-9 psi, maxed out at +15% for mid 11's AFR, 550x720 setting. You could set for 550x550 and get another +25% fuel, and it wouldnt be difficult retune with your setup, since all your injectors are the same size
The next release will have an increased range of adjustment: +/-30%.
-Henrik
Cool man, thanks.
The only thing I worry about is if I set the injectors to 550/550 that I might not be able to tune the top end down enough. I might try it now. I already have the injectors set to 550/720 because it ran to lean at idle for some reason.
I'll see what it does. I'll keep my fuel trim down low the same but up high bring it down some.
I don't think the injectors are maxing out. Its just that there isn't any more room to adjust up. The duty cycles that I'm getting suggest that I can get more out of the injectors, way more.
Well I just back from messing with the settings. I set the injectors to 550/550 and did a pull. I instantly saw much richer conditions. Like in the low 10's so I leaned it out across the board from 10 psi to 12 psi. Did a couple of pulls and got it into the high 10's low 11's.
I don't think I have the input for the wideband setup right. I think the palm is reading a little high so I might set it better later. When I'm watching the wideband display it reads rich even with it leaned out a little.
I'm going to keep it where its at for now and do some more pulls later, but I think there might be enough fuel up to 14psi now. 14psi map I left maxed out for now because I haven't done a pull that high yet so I don't know how its going to act.
Location: Arizona desert, where the terraplanes roam.
Posts: 118
WOW, nice job.
It looks like you have plenty of fuel at the 10psi+ range.
So if we switch to 550/550, we get approx. 25% more fuel but we can only adjust down 15% which leaves and extra 10% that would make us rich.
I was concerned that the idle would be way too rich, but your at 12.5 which semms ok. Are you at full -15% at idle?
What kind of adjustment range do you have.
Any concerns at 550/550?
Thanks to you, I'm going to try it.
Damn, 10psi is maxing out 4x720 at 11a/f... I figured that would be good for at least 15psi, but I guess I was wrong
oh i didnt mean the injectors were maxed, only the adjustment with the 550x720 setting. I am only getting 36% duty cycle at 9psi, 3rd gear, mid 11's AFR. This is with stock ports and stock turbo though
So if we switch to 550/550, we get approx. 25% more fuel but we can only adjust down 15% which leaves and extra 10% that would make us rich.
yes, but if you were lean at +15% with the 720 setting then -15% on the 550 setting would be like +10 on the 720 setting so there is some overlap....
Overall is -40% at 720 and -15%
Overall is -25% at 720 and 0%
Overall is -10% at 720 setting and +15%
Overall is -10% at 550 and -10%
Overall is 0 at 550 and 0%
Overall is +15 at 550 an 15%
So as of right now, there is a 5% overlap. (720 and +15% will give you 5% more fuel than 550 at -15%.)
Though it could still be a problem if on the 720 setting you were set to less that +10%...or leaning out the 720s down low.
ynkeetratr: Did you view the files with a palm or the PLviewer? If you viewed it with the PLviewer how do you adjust the analog input to read 9.0-14.7 AFR's instead of 1-5 volts? Or did you just convert it from the top of your head?
I don't remember what I have it set at idle, but it isn't in the negative. I think I just left it alone. I like keeping it in the 12's because when my E-fan kicks on at idle it spikes the AFR's to low 13's. I still have alot of work to do on the low end or all around really. I'm on the plus side of the adjustments right now. Driving around town today my wideband display still reads rich. So I'm going to lean it out just a little more in some points.
I still have +5 - +10 to work with. If I lean it out in some points I might have more.
I don't see any concerns using the 550/550 setting. I just wish I had used it from the start.
I have less of a hickup now also when the secondaries kick on. Feels very smooth through the RPM band.
Location: Arizona desert, where the terraplanes roam.
Posts: 118
(yes, but if you were lean at +15% with the 720 setting then -15% on the 550 setting would be like +10 on the 720 setting so there is some overlap....)
I agree. This is good for the top/boosted range. Good solution
(Though it could still be a problem if on the 720 setting you were set to less that +10%...or leaning out the 720s down low.)
I'm at -1.8% at idle to get a 13.0 AFR using 720/720 at idle so I'm concerned that running 550/550 will give me even more fuel that I can't trim to get a good idle AFR. 95nracer got a 12.5 AFR without trim, so I can live with that.
I'm not sure if I'm interpreting all the "overall " stuff correclty. My slow brain will have to study it.
95nracer, I use 0V=9.6/5V=19.60 per Zeitronix WB.
Tutbo2ltr, what is the PL viewer parameter settings for the air flow? If I adjust to 0-43lbs/min. I still get the 0-1000 scale.
We tuned all the way back from SS9 slowing down and making 3rd gear pulls. The engine really likes fuel.
I need to get on the back desert roads this week and make some pulls.
Location: Arizona desert, where the terraplanes roam.
Posts: 118
OK, Reset the Rtek to 550/550 and zeroed the fuel.
Upon start-up it ran rough and adjusted the fuel at 2000 rpm to -15%. I went from 10 AFRs to 11.5AFRs. I was concerned that I was out of adjustment but then adjusted the idle pot to lean and brought it to 12.9-13.1 at idle. I likey.
Boy there's alot of adjustment range in that pot.
Ran around the block and tried some 0 psi mild pulls. Iv'e read that a 13.0 AFR at transition (0 psi) is ok. I was a little rich with my initial stab at a fuel curve but I think I can dial it in.
Linear Mode
