New chip available for S4 TII's
12-01-03, 05:07 PM
#51
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Originally posted by HAILERS
Just a note. At idle, fully warmed up, my variable resistor reads 1.65volts and the afr is 13.0 give or take .1 If the electrical plug is removed from the variable resistor, the afr goes to 13.5 give or take .1
Just a note. At idle, fully warmed up, my variable resistor reads 1.65volts and the afr is 13.0 give or take .1 If the electrical plug is removed from the variable resistor, the afr goes to 13.5 give or take .1
12-01-03, 08:22 PM
#52
what language is the ECU code in BTW? just kinda curious, would you want to post the source? What are you using to edit/compile it etc...? tis ok if you cant answer some of them because you want to protect your product im just very intrested in this kinda stuff.
12-04-03, 03:51 PM
#53
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Originally posted by Digi7ech
Henrik you rock.
This is a great idea and I'm amazed no one else has really done this.
If I didn't just buy a FCD and ECU I would have bought yours.
From what I understood the ECU cut fuel to the rear rotors at a calculated pressure.
The FCD's would then trick the ECU into thinking the pressure is below that number.
I've heard this makes the car lean out a bit over that limit because the ECU still thinks it's running X amount of pressure instead of like 10psi and does not provide sufficient fuel.
I'm a turbo newb so I'm just learning this. Is the above somewhat true?
Would your modded ECU keep adding fuel after the original cut level as if the cut level never existed?
Henrik you rock.
This is a great idea and I'm amazed no one else has really done this.
If I didn't just buy a FCD and ECU I would have bought yours.
From what I understood the ECU cut fuel to the rear rotors at a calculated pressure.
The FCD's would then trick the ECU into thinking the pressure is below that number.
I've heard this makes the car lean out a bit over that limit because the ECU still thinks it's running X amount of pressure instead of like 10psi and does not provide sufficient fuel.
I'm a turbo newb so I'm just learning this. Is the above somewhat true?
Would your modded ECU keep adding fuel after the original cut level as if the cut level never existed?
bump for this question as it is important to me and im sure others.... if it does continue to add more fuel past 8.6 psi, thus eliminating the need for major fuel upgrades i would be interested for sure, and would FOR SURE purchase this product...
any info would be great!
thanks!
12-04-03, 04:04 PM
#54
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If they make a modded ECU that will control 720cc's without any other supporting electronic mods I'm in (even IF the maps are very conservative). These guys ROCK, the pocketlogger is what makes my GVR4 and many many other DSM's faaaaast. Before the logger came out who knows how badly DSM's were knocking and getting timing yanked - these guys knw their stuff!!
12-04-03, 05:08 PM
#56
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NO!!!! 
more important is if the upgrade continues to add fuel or not....
if im thinking correctly that would eliminate (or atleast lessen) the need for costly fuel upgrades...
if thats the case, then count me in
more important is if the upgrade continues to add fuel or not....
if im thinking correctly that would eliminate (or atleast lessen) the need for costly fuel upgrades...
if thats the case, then count me in
12-04-03, 08:12 PM
#58
Originally posted by Peruvianrx7
MORE INFO!!! on the s4 naturally aspired engines =) wouldnt stopping the AWS ( the thing that makes the engine rev to 3k) be bad?
MORE INFO!!! on the s4 naturally aspired engines =) wouldnt stopping the AWS ( the thing that makes the engine rev to 3k) be bad?
Revving a cold engine to 3k on instant start up is BAD!
That's why you let the car get to running temp before you give it gas.
Besides I have heard the AWS was added to US ECU's to help make the useless precats work for start up emissions.
So tossing the precats and getting rid of the horrid AWS is good.
BTW Icemarks note in the FAQ saying put it in gear doesn't stop it on mine from revving.
12-05-03, 10:39 AM
#63
Former Moderator. RIP Icemark.
Originally posted by Digi7ech
BTW Icemarks note in the FAQ saying put it in gear doesn't stop it on mine from revving.
BTW Icemarks note in the FAQ saying put it in gear doesn't stop it on mine from revving.
12-05-03, 01:36 PM
#65
Yeah both my FC's do it. So i guess their both busted. Oh well. Doesn't bother me.
BACK TO TOPIC!!!!!!
Does the fuel map continue after the current cut level if the FCD signal is removed?Any Idea of how high it goes?
Definitely a very good mod for people doing daily driver 10psi cars.
BACK TO TOPIC!!!!!!
Does the fuel map continue after the current cut level if the FCD signal is removed?Any Idea of how high it goes?
Definitely a very good mod for people doing daily driver 10psi cars.
12-07-03, 02:13 AM
#67
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Let me try again on the fuel map topic. Basic fueling in the FC ECU works like this:
For each rev there is one squirt of each primary injector. If the conditions are correct for secondary then they also fire. Front/rear injectors fire at different times but primary/secondary always fire together.
The ECU calculates each squirt as follows:
1. read AFM and linearize (AFM is a highly nonlinear sensor). This gives air volume.
2. read ATP and AFM temp sensor. Use these to correct air volume into air mass
3. turn into discrete durations based on rpm and injector size.
4. compute corrections for various conditions such as cold engine, throttle enrichment, etc. and boost/rpms. The boost/rpms corrections are maps with the boost map topping out at ~1.6psi. Above ~1.6psi the boost sensor plays no role in adding fuel (rpm's does though)
Because these cars have AFM's, there will be additional fuel added for boosting above the FCD setpoint (as the ECU sees the extra airflow via the AFM). The ECU does not add extra fuel per psi boost beyond the ~1.6psi mark. My mod does not change this (although I could add a correction if people wanted).
Extrapolating from the datalogging I've done, it looks like the ECU, AFM and injectors will be good up to around 10psi - maybe this is why people say there are maps to 10psi? Above 10psi, the injector duty cycle will start maxing and the engine will start runninng leaner than factory settings. Fuel pump wont help with this unless your going higher than stock rail pressures.
-Henrik
For each rev there is one squirt of each primary injector. If the conditions are correct for secondary then they also fire. Front/rear injectors fire at different times but primary/secondary always fire together.
The ECU calculates each squirt as follows:
1. read AFM and linearize (AFM is a highly nonlinear sensor). This gives air volume.
2. read ATP and AFM temp sensor. Use these to correct air volume into air mass
3. turn into discrete durations based on rpm and injector size.
4. compute corrections for various conditions such as cold engine, throttle enrichment, etc. and boost/rpms. The boost/rpms corrections are maps with the boost map topping out at ~1.6psi. Above ~1.6psi the boost sensor plays no role in adding fuel (rpm's does though)
Because these cars have AFM's, there will be additional fuel added for boosting above the FCD setpoint (as the ECU sees the extra airflow via the AFM). The ECU does not add extra fuel per psi boost beyond the ~1.6psi mark. My mod does not change this (although I could add a correction if people wanted).
Extrapolating from the datalogging I've done, it looks like the ECU, AFM and injectors will be good up to around 10psi - maybe this is why people say there are maps to 10psi? Above 10psi, the injector duty cycle will start maxing and the engine will start runninng leaner than factory settings. Fuel pump wont help with this unless your going higher than stock rail pressures.
-Henrik
12-07-03, 02:18 AM
#68
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Originally posted by J-Rat
Hailers just said, there are "maps" to 10 PSI, if the FCD is eliminated!
and I WANT ADJUSTABLE REV LIMITER!
Hailers just said, there are "maps" to 10 PSI, if the FCD is eliminated!
and I WANT ADJUSTABLE REV LIMITER!
-Henrik
12-07-03, 02:25 AM
#69
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Originally posted by Peruvianrx7
oh im sorry so what should i do... they dont make them for an N/a s4 do they?
oh im sorry so what should i do... they dont make them for an N/a s4 do they?
-Henrik
12-07-03, 07:01 AM
#70
HAILERS
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Hailers agrees he was, well, confused about the fuel non issue. He stands corrected.
Now here is a phenomen that has been puzzeling me for awhile. I've seen it on turbo and non turbo cars. Say your driving along the hwy. Say fifty mph on a level stretch. Now you come to a downhill section of road. You see a copper at the bottom of the hill. You want to maintain a perfect fifty mph (posted speed limit). So now that your going downhill you have to lift just a tiny amount to not exceed fifty. When this tiny amount of lifting is done......you'll see you air fuel gauge whether wideband or narrow band, go rich. Say it was 14.7 before you lifted. Now it's a full point lower (rich) at 13.5
Question: what causes that momentary rich condition??? An accelerator pump???(on lifting off the throttle?). The same can be monitored with a digtial meter tapped to pin 2D on a series four. And by the way, as soon as I step just a smidge back on the pedal, the afr goes back to the 14.7. Why bother asking, you ask. Well say your on a emissions dyno where they test at 15 and then 25mph. What if Mr Bozzo who is testing, reaches 25mph on the dyno and then lifts to hold 25? What happens...the afr goes from a 14.7 to 13.6 or so. Not a good thing. I think its pressure sensor related. I'm gonna pull my vac hose off it today and see what the results are.
Now here is a phenomen that has been puzzeling me for awhile. I've seen it on turbo and non turbo cars. Say your driving along the hwy. Say fifty mph on a level stretch. Now you come to a downhill section of road. You see a copper at the bottom of the hill. You want to maintain a perfect fifty mph (posted speed limit). So now that your going downhill you have to lift just a tiny amount to not exceed fifty. When this tiny amount of lifting is done......you'll see you air fuel gauge whether wideband or narrow band, go rich. Say it was 14.7 before you lifted. Now it's a full point lower (rich) at 13.5
Question: what causes that momentary rich condition??? An accelerator pump???(on lifting off the throttle?). The same can be monitored with a digtial meter tapped to pin 2D on a series four. And by the way, as soon as I step just a smidge back on the pedal, the afr goes back to the 14.7. Why bother asking, you ask. Well say your on a emissions dyno where they test at 15 and then 25mph. What if Mr Bozzo who is testing, reaches 25mph on the dyno and then lifts to hold 25? What happens...the afr goes from a 14.7 to 13.6 or so. Not a good thing. I think its pressure sensor related. I'm gonna pull my vac hose off it today and see what the results are.
12-10-03, 12:23 PM
#71
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I've read that the S5 pressure sensors are used to adjust timing, and fuel delivery as well as fuel cut. and on S4 models, the sensors are used for timing and fuel cut only. the only thing i'm worried about it the timing issue. what happens to ignition timing after 8.6 psi. if the ECU doesn't know you're running 10 or so pounds then the timing will be advanced. maybe it's only a degree or so, but what if i want to run 12 psi or maybe 14? i kept hitting fuel cut at the drag strip last weekend so i just unplugged the damn sensor. seemed to work fine. i made a few passes and hooked it back up.
Last edited by fstrnyou; 12-10-03 at 12:29 PM.
12-10-03, 02:13 PM
#73
Originally posted by Henrik
The ECU does not add extra fuel per psi boost beyond the ~1.6psi mark. My mod does not change this (although I could add a correction if people wanted).
The ECU does not add extra fuel per psi boost beyond the ~1.6psi mark. My mod does not change this (although I could add a correction if people wanted).
12-10-03, 02:24 PM
#74
Originally posted by Henrik
I'm not sure I can do an ignition cut, (cut rev limit is a fuel cut), I'll have to dig a bit on that one. What sort adjustability are you looking for?
-Henrik
I'm not sure I can do an ignition cut, (cut rev limit is a fuel cut), I'll have to dig a bit on that one. What sort adjustability are you looking for?
-Henrik
Problems with that are, fuel cut on a boosted car is not smart and the system doesnt control the revs very well.
Now here is what I would like:
A built in 2 step system. This would allow the ECU to limit revs to the 4000/5000 area with the clutch pedal depressed. Then an adjustable rev range of 6500 to basically 11/1200 (if anyone wants to wrap that high). I would imagine that in the interest of simplicity, you could use DIP switches, and give us 250 or 500 incrememtal adjustments.
What I would settle for:
An adjustable rev limiter 6500-11/1200.
Only reason I HAVENT purchased the chip yet:
A: My car doesnt flood
B: I already have an FCD
C: My AWS has been disabled by other means (IE removal of the components involved)
Jarrett
12-10-03, 04:20 PM
#75
I'm a boost creep...
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Originally posted by J-Rat
So in essence, setting the FCD to clamp the voltage at a resolved 1.6 PSI, would not be any different (fuel delivery wise), then if it clamped at a resolved 8 PSI, (or just at fuel cut)????
So in essence, setting the FCD to clamp the voltage at a resolved 1.6 PSI, would not be any different (fuel delivery wise), then if it clamped at a resolved 8 PSI, (or just at fuel cut)????
...fuel cut on a boosted car is not smart...