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Don Supreme
11-13-2008, 02:02 PM
Ok guys....

No stupid comments here. If you don't understand the nature of these questions then please just read.

My current tune is less than ideal. I am running it temporarily until I move onto better things. I have tweaked the hell out of it using lemmiwinks, but I am concerned about something.


Situation A:

If I step on the gas from 4000 RPM or so, the AFRs come into spec (decent, not perfect) and hold in a fairly safe range until I let off. Please see screenshot below (Run started from 4500 RPM or so).

http://www.wisptech.net/images/misc/4500punch.JPG


Situation B: If I step on the gas past the boost threshold, lets says 5100 RPM + -- The boost comes on QUICK, and then I look at my wideband and its reading some crazy lean values and then everything catches up.

I am worried that my injectors or tune for injectors are not keeping up, and too slow to respond. 24 PSI and 13.5 AFR is does not seem right (even if it is for only a split second). If you pay attention to the market location #2, the AFRS are in 14s and then it drops down to the 11s.

See screenshot below:

http://www.wisptech.net/images/misc/5100punch.JPG


What you guys think? Normal or what?

offroader1006
11-13-2008, 02:05 PM
hard to tell without timestamps how long it actually sits at a lean mixture.

it will usually take a split second for the ecu to get its calculations into physical changes.

if you were in a low gear 5100-5500 doesnt take long

Don Supreme
11-13-2008, 02:08 PM
hard to tell without timestamps how long it actually sits at a lean mixture.

it will usually take a split second for the ecu to get its calculations into physical changes.

if you were in a low gear 5100-5500 doesnt take long

The second screenshot is 4th gear.

b5s4tt
11-13-2008, 02:08 PM
wat size injectors

Don Supreme
11-13-2008, 02:09 PM
wat size injectors

630cc @ 4 bar.

pac1085
11-13-2008, 02:22 PM
On my ECU you need to tune the 'acceleration enrichment' to work that out, however there is always a very brief period where it might spike lean, since the ECU needs to register the drastic change in MAP value before it can fully compensate

bassed
11-13-2008, 02:23 PM
Not normal, it richens then leans than richens. Lemmi is static logarythms not progressive algorythms and can be very very dangerous what channels are you adjusting and by what deviation from default? You're tunning and injectors could be fine down the line, but I would think the 630's and the HTA35 are not paired correctly.

solowb5
11-13-2008, 02:27 PM
What kind of a wideband are you using and how is it hooked up? ie power supply wise.

Don Supreme
11-13-2008, 02:28 PM
Not normal, it richens then leans than richens. Lemmi is static logarythms not progressive algorythms and can be very very dangerous what channels are you adjusting and by what deviation from default?

The rich then lean you are seeing is the from 0 psi boost to 20+ psi boost --- so don't focus on that part.

What exactly are you saying when you use the word "logarythms"......?

Don Supreme
11-13-2008, 02:30 PM
What kind of a wideband are you using and how is it hooked up? ie power supply wise.

Its powered near the fuse box behind the bolters... Maybe 75x? I don't think that matters.

Zeitronix.

1NaudiA4
11-13-2008, 02:30 PM
At 23psi on my HTA30r with 860's I was running about 85% duty cycle. You have to be very close to 100% with 630's and a HTA35r. As for the AFR as pac1085 said you need to play with the acceleration enrichment to get it to richen up right away when you press on the gas.

Don Supreme
11-13-2008, 02:31 PM
People usually post afr logs of entire gear pulls have you guys actually taken the time to analyze what happens when you stomp on it @ 6000 RPM?

Don Supreme
11-13-2008, 02:33 PM
At 23psi on my HTA30r with 860's I was running about 85% duty cycle. You have to be very close to 100% with 630's and a HTA35r. As for the AFR as pac1085 said you need to play with the acceleration enrichment to get it to richen up right away when you press on the gas.

I had Ch02 : Fuel Tweak (Accel Pump); Increasing Loads
-This channel adjusts a fuel enrichment under load

Jacked up to +15% during those logs..... I guess I could try pushing that up even more!

solowb5
11-13-2008, 02:33 PM
I asked that bc I ran an AEM wideband at first and it didn't last worth a shit. I then used a LC-1 wideband w/led guage. I just ran it from a 12+ source and at full throttle it would read crazy lean and sometimes freeze up. So I ran it on it's own relay straight from the battery and that fixed the problem. Seems it needs a very good power source. Just thought that may be a reason to seeing crazy a/f readings. Just suggesting it bc I haven't had any experiance with zeitronix.

Don Supreme
11-13-2008, 02:36 PM
I asked that bc I ran an AEM wideband at first and it didn't last worth a shit. I then used a LC-1 wideband w/led guage. I just ran it from a 12+ source and at full throttle it would read crazy lean and sometimes freeze up. So I ran it on it's own relay straight from the battery and that fixed the problem. Seems it needs a very good power source. Just thought that may be a reason to seeing crazy a/f readings. Just suggesting it bc I haven't had any experiance with zeitronix.

Well, as I posted, the AFRs are fine if I start accdlerating from early enough.... Its more of a reaction time thing.

bassed
11-13-2008, 02:46 PM
Logarithm I spelled it wrong the first time is more or less static it holds the same value across the board. So your increasing a channel is the same from 1k to 8k RPMS with Lemmi being a Logarithm based app. it's not progressive sequence of infinite instruction like that of a Alorithm (what our ECU does). I am not a big fan of these applications like Lemmi for just this reason, it's static not progressive. Values are the same all the way through when using Lemmi/UNITUNE/CTAPPS etc... they're all the same at the moment and none of them recomend most people to use them.

Don Supreme
11-13-2008, 03:07 PM
Logarithm I spelled it wrong the first time is more or less static it holds the same value across the board. So your increasing a channel is the same from 1k to 8k RPMS with Lemmi being a Logarithm based app. it's not progressive sequence of infinite instruction like that of a Alorithm (what our ECU does). I am not a big fan of these applications like Lemmi for just this reason, it's static not progressive. Values are the same all the way through when using Lemmi/UNITUNE/CTAPPS etc... they're all the same at the moment and none of them recomend most people to use them.

I thought thats what you meant, but....

Lemmiwinks is not real tuning, but its a great tool to get a car running decently.... My AFRrs would be deep into the 13s without lemmi.

Better things to come.

Don Supreme
11-13-2008, 03:09 PM
At 23psi on my HTA30r with 860's I was running about 85% duty cycle. You have to be very close to 100% with 630's and a HTA35r. As for the AFR as pac1085 said you need to play with the acceleration enrichment to get it to richen up right away when you press on the gas.

duty cycle is pretty much maxxed, but not @ 5100 RPM -- Its only 71-74% @ 5100, so thats not the issue. Its a tuning / response thing.

Properly 'driven' low Z injectors would probably help.

mike-2ptzero
11-13-2008, 04:29 PM
Almost sounds like the ecu just dumps fuel, corrects and then gets back to where it should be.