FAST/Gen7/BS3 Users, jump in here....
Thread Starter
Joined: Nov 2001
Posts: 45,326
Likes: 1,767
From: Chicago, IL
FAST/Gen7/BS3 Users, jump in here.... A few questions, if you have time to reply...
1) VE numbers?
2) AF at idle?
3) AF at part throttle?
4) Are you open loop and then closed loop at 1500 or what are you doing?
1) VE numbers?
2) AF at idle?
3) AF at part throttle?
4) Are you open loop and then closed loop at 1500 or what are you doing?
my ve ranges from around .4 at idle to around .96 at 15psi or so. wide range depends on boost and rpm
my idle a/f is like 13.9
my part throttle a/f depends on how much vaccum its at durning that throttle (map/rpm referenced just like ve) but light load is same as idle.
my car runs closed loop all the time after the coolant gets to 100*
my idle a/f is like 13.9
my part throttle a/f depends on how much vaccum its at durning that throttle (map/rpm referenced just like ve) but light load is same as idle.
my car runs closed loop all the time after the coolant gets to 100*
1. normally around 100 at peak torque, then slowly drop off.
2. Depends on how well the headers and collectors are sealed. Normal around 12.5-13.2
3.around 14-1
4. Normally don't go closed loop until I'm over the transbrake rpm. I would set it to go closed loop 200 rpm above the rpm when you floor the car on the brake.
Good luck
Kurt
2. Depends on how well the headers and collectors are sealed. Normal around 12.5-13.2
3.around 14-1
4. Normally don't go closed loop until I'm over the transbrake rpm. I would set it to go closed loop 200 rpm above the rpm when you floor the car on the brake.
Good luck
Kurt
Originally Posted by Pro Stock John
A few questions, if you have time to reply...
1) VE numbers?
2) AF at idle?
3) AF at part throttle?
4) Are you open loop and then closed loop at 1500 or what are you doing?
1) VE numbers?
2) AF at idle?
3) AF at part throttle?
4) Are you open loop and then closed loop at 1500 or what are you doing?
Thread Starter
Joined: Nov 2001
Posts: 45,326
Likes: 1,767
From: Chicago, IL
1) I was thinking base VE like at idle but your answers are very useful, we've been playing with putting my idle VE anywhere from 45 to 55.
2) I"m around 13.1 right now at idle.
3) I"m at 12:1 I need to lean that out probably to 13-14:1 under light load (no boost).
4) We tuned in open loop up to 3000 so far, my t'brake rpm would probably be 4500.
2) I"m around 13.1 right now at idle.
3) I"m at 12:1 I need to lean that out probably to 13-14:1 under light load (no boost).
4) We tuned in open loop up to 3000 so far, my t'brake rpm would probably be 4500.
MM the 02 being on is a problem for me on the brake for a couple different reasons.
1. The 02 reacts to fast and overshoots the target AF ratio on both the rich and lean side. If you slow down its reaction then its to slow to correct during the run.
2. I have many times needed a two step rpm device to maintain traction by lowering the power on the starting line. This causes raw fuel to load the ex sending the 02 into a false zone that it can't recover from fast once the brake is released.
3. The surge from the 02 readings causes the engine rpm to raise and lower on the brake. This is the worst thing for a driver as it can take your attention from the job at hand.
When my tune up is right I record the 02 for info but I race in open loop, it makes the car faster.
Which system do you use on your car? Does it correct on every run? What type of 02 are you using?
Kurt
1. The 02 reacts to fast and overshoots the target AF ratio on both the rich and lean side. If you slow down its reaction then its to slow to correct during the run.
2. I have many times needed a two step rpm device to maintain traction by lowering the power on the starting line. This causes raw fuel to load the ex sending the 02 into a false zone that it can't recover from fast once the brake is released.
3. The surge from the 02 readings causes the engine rpm to raise and lower on the brake. This is the worst thing for a driver as it can take your attention from the job at hand.
When my tune up is right I record the 02 for info but I race in open loop, it makes the car faster.
Which system do you use on your car? Does it correct on every run? What type of 02 are you using?
Kurt
Originally Posted by MIGHTYMOUSE
if your sure your 02 is accurate then why dont you put it in closed loop and let it do the tuning for you? or is dfi different?
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Verdad Gallardo its gen 7 and whichever sensor they send with the wideband option.
i have a little bit of an overshoot problem when i initially stab it.. would be interesting to see if it goes away if i change some stuff..
an interesting table on gen 7 is allowed correction vs rpm and boost. you guys have that?
you could tune the max % 02 correction down to little or nothing in the areas you are talking about and still be in closed loop everywhere.
i have a little bit of an overshoot problem when i initially stab it.. would be interesting to see if it goes away if i change some stuff..
an interesting table on gen 7 is allowed correction vs rpm and boost. you guys have that?
you could tune the max % 02 correction down to little or nothing in the areas you are talking about and still be in closed loop everywhere.
MM, My correction limits are based on boost/ map. I cannot change them based on brake on or off. If I cut down the correction at a set boost level then if I hit that zone in a run it would not correct.
I guess everybody has a different way of tuning, although we all strive for the same thing(more POWER)! The wide band is a tuning tool we use to get our fuel map right. When the car goes down the track in a perfect world the 02 would be off.
Kurt
I guess everybody has a different way of tuning, although we all strive for the same thing(more POWER)! The wide band is a tuning tool we use to get our fuel map right. When the car goes down the track in a perfect world the 02 would be off.
Kurt
Originally Posted by MIGHTYMOUSE
its gen 7 and whichever sensor they send with the wideband option.
i have a little bit of an overshoot problem when i initially stab it.. would be interesting to see if it goes away if i change some stuff..
an interesting table on gen 7 is allowed correction vs rpm and boost. you guys have that?
you could tune the max % 02 correction down to little or nothing in the areas you are talking about and still be in closed loop everywhere.
i have a little bit of an overshoot problem when i initially stab it.. would be interesting to see if it goes away if i change some stuff..
an interesting table on gen 7 is allowed correction vs rpm and boost. you guys have that?
you could tune the max % 02 correction down to little or nothing in the areas you are talking about and still be in closed loop everywhere.
Thread Starter
Joined: Nov 2001
Posts: 45,326
Likes: 1,767
From: Chicago, IL
Great replies. Kurt, I was thinking you were doing open loop up that high to deal with some sort of overshoot problem.... I will do the same. We can easily tune open loop to 4500.
Kurt, we're debating going full standalone, here is what we see as the pros and cons, what are your thoughts (if we remove the pcm and engine control harness):
+ more room
+ less wires to chase when having problems
- need to wire up custom fan switch? Can do thru the FAST?
- need to wire up custom water pump switch? Can do thru the FAST?
- need to wire up custom oil temp, coolant temp, and fuel gauges
Anything else that runs off the engine control harness that we would need to address?
Kurt, we're debating going full standalone, here is what we see as the pros and cons, what are your thoughts (if we remove the pcm and engine control harness):
+ more room
+ less wires to chase when having problems
- need to wire up custom fan switch? Can do thru the FAST?
- need to wire up custom water pump switch? Can do thru the FAST?
- need to wire up custom oil temp, coolant temp, and fuel gauges
Anything else that runs off the engine control harness that we would need to address?
i hope to eventually arrive at that, but for now i just drive around putting the car in different load cells and tapping the auto calc button as i go along.... but i'm all over the map with the tubo so thats why its hard for me to cut the adjustment from the computer as it may hit cells that ive not touched yet.
John,
I vote for complete standalone.
The FAST will kick on the fan.
The waterpump should come on with the key.
I think your factory ECU controls your alternator output also.
The gauges part is a little expensive but what the hell its only money!
Kurt
I vote for complete standalone.
The FAST will kick on the fan.
The waterpump should come on with the key.
I think your factory ECU controls your alternator output also.
The gauges part is a little expensive but what the hell its only money!
Kurt
Originally Posted by Pro Stock John
Great replies. Kurt, I was thinking you were doing open loop up that high to deal with some sort of overshoot problem.... I will do the same. We can easily tune open loop to 4500.
Kurt, we're debating going full standalone, here is what we see as the pros and cons, what are your thoughts (if we remove the pcm and engine control harness):
+ more room
+ less wires to chase when having problems
- need to wire up custom fan switch? Can do thru the FAST?
- need to wire up custom water pump switch? Can do thru the FAST?
- need to wire up custom oil temp, coolant temp, and fuel gauges
Anything else that runs off the engine control harness that we would need to address?
Kurt, we're debating going full standalone, here is what we see as the pros and cons, what are your thoughts (if we remove the pcm and engine control harness):
+ more room
+ less wires to chase when having problems
- need to wire up custom fan switch? Can do thru the FAST?
- need to wire up custom water pump switch? Can do thru the FAST?
- need to wire up custom oil temp, coolant temp, and fuel gauges
Anything else that runs off the engine control harness that we would need to address?
You will get there!! It just takes time and patience.
I mostly run cars on drag strips. The cal on a drag car is much simpler to do. We only need a burnout and wot! The street stuff is faster if you get someone else to drive.( I will drive)
Kurt
I mostly run cars on drag strips. The cal on a drag car is much simpler to do. We only need a burnout and wot! The street stuff is faster if you get someone else to drive.( I will drive)
Kurt
Originally Posted by MIGHTYMOUSE
i hope to eventually arrive at that, but for now i just drive around putting the car in different load cells and tapping the auto calc button as i go along.... but i'm all over the map with the tubo so thats why its hard for me to cut the adjustment from the computer as it may hit cells that ive not touched yet.