How do I solve the problem of knock retard when the alky turns on? When the alky turns on the FAST XFI tries to take out fuel when the afr goes way rich. It takes out too much fuel and then the knock continues because the afr goes lean. My alky settings are the ones that Razor had set when the kit arrived.
Knock retard when alky turns on.
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Your sig says SMC. You have an SMC or my system?
What you do is trim fuel out of the turnon point and do this with the correction OFF. You cannot tune your computer if the correction is "ON" as it will swing the numbers.
You have two options, make the correction zero in that turnon area or set the correction to start at a higher boost level.. lets say 4800 RPM's. On cars with 2-steps you want the correction to be off while on the 2 step.
Once you have it dialed in with correction "OFF".. turn the correction "ON" if you wish.
There are other tables like AE vs MAP, AE vs CLT, AE vs TPS, etc that can affect how fuel is dumped in and cause problems.
Correction should be used for minor adjustments not fix tuning issues.
What you do is trim fuel out of the turnon point and do this with the correction OFF. You cannot tune your computer if the correction is "ON" as it will swing the numbers.
You have two options, make the correction zero in that turnon area or set the correction to start at a higher boost level.. lets say 4800 RPM's. On cars with 2-steps you want the correction to be off while on the 2 step.
Once you have it dialed in with correction "OFF".. turn the correction "ON" if you wish.
There are other tables like AE vs MAP, AE vs CLT, AE vs TPS, etc that can affect how fuel is dumped in and cause problems.
Correction should be used for minor adjustments not fix tuning issues.
I have your system. I left my sig. that way because that combo ran the time posted and I have not bettered it yet. 
The car currently runs great after I get through the turn on point knock retard (6.967 @ 100.58 with 1.613 60'). The correction is currently set to 5.
If I want to change the turn on point, what knob do I use and which way do I turn it?
If I want to slow down the ramp up, which knob do I use and which way do I turn it?
Thanks for the help.
The car currently runs great after I get through the turn on point knock retard (6.967 @ 100.58 with 1.613 60'). The correction is currently set to 5.If I want to change the turn on point, what knob do I use and which way do I turn it?
If I want to slow down the ramp up, which knob do I use and which way do I turn it?
Thanks for the help.
^ whos tunning the car? where did you get the XFI? I can tell you one thing for sure. make sure you have a good tuner. my current tuner made a huge difference in my cars tune. it would launch adding max fuel, go pig rich and try to correct then it would even out. now it lauches with adding fuel and then it has a stair looking drop to the perfect a/f and no correction.
with that being said make sure you have a good tuner and he can dail it in for you.
with that being said make sure you have a good tuner and he can dail it in for you.
I have your system. I left my sig. that way because that combo ran the time posted and I have not bettered it yet.
If I want to change the turn on point, what knob do I use and which way do I turn it?
If I want to slow down the ramp up, which knob do I use and which way do I turn it?
Thanks for the help.
Inside the PAC there is a control labeled "Turnon" that changes when the kit "turns on". Turning the control CW increases when it activates.
To slow down ramp, reduce gain. To reduce alcohol across the board.. reduce "Initial" inside the controller.
Say it this way, typically on my system you leave it alone and tune the FAST around it. Just put the Gain knob on 6 and tune your Fast.
You need to tune your FAST for the alky. this is hard to do over a keyboard on an internet forum. If you/your tuner need some help.. call me.
Hi Jim,
I overheard your conversation about this subject with Pat (SloGN) last night. He’s correct that the FAST XFI doesn’t have any control over the Alkycontrol kit. All the XFI sees is the A/F going rich for some reason and starts pulling fuel to compensate. The only thing to do is to anticipate in the tune when the alky comes in and compensate for that extra fuel. I know in speaking with Pat in the past, he has a strategy in his tunes to add fuel quickly and slowly remove fuel. Maybe because the alky comes in strong, the tune should allow more aggressive removal of fuel.
I’ll be learning the XFI soon myself and most likely be in the same boat as you are. The only difference is that I have a alky pressure transducer which I plan on hooking up to the XFI. I just don’t know that the XFI can use the information from the transducer to adjust the tune, or if the transducer is just going to give me a datapoint that I can log.
I overheard your conversation about this subject with Pat (SloGN) last night. He’s correct that the FAST XFI doesn’t have any control over the Alkycontrol kit. All the XFI sees is the A/F going rich for some reason and starts pulling fuel to compensate. The only thing to do is to anticipate in the tune when the alky comes in and compensate for that extra fuel. I know in speaking with Pat in the past, he has a strategy in his tunes to add fuel quickly and slowly remove fuel. Maybe because the alky comes in strong, the tune should allow more aggressive removal of fuel.
I’ll be learning the XFI soon myself and most likely be in the same boat as you are. The only difference is that I have a alky pressure transducer which I plan on hooking up to the XFI. I just don’t know that the XFI can use the information from the transducer to adjust the tune, or if the transducer is just going to give me a datapoint that I can log.
Eric,
Pat will get it right. He has already reduced the fuel input. I hope to have my tune figured out by the time you get your motor back together in 2012.
Yeah, that Thanksgiving projection is pretty much shot at this point. I'll be lucky to get the transmission done by then
No.. "IF" the FAST was tuned without alcohol being shot in.. then you throw alcohol on top of the tune of course its going to go rich.
If you tune the FAST and do so with the alcohol rolling in.. then its a non issue.
The only issue you may have is kit is not purged and when going into boost your air fuel goes slightly lean.. the fix is set correction to add fuel not pull it from the turnon area.
The way all of this is fixed pretty easy.. turn off the correction..arm the datalogger.. and go into boost so it starts recording.. like 0-15 PSI. Shut engine off.. play back your datalog.. and fix your VE table. Repeat until your air fuel matches your target. Once it does this.. turn on correction if you want.. it should not have to do much..
Question !
Hope I'm asking this right but would it be worth while using an out put signal from the XFI to trigger the alky pump so everything works more in harmony instead of independent of each other or would this be redundant.
Hope I'm asking this right but would it be worth while using an out put signal from the XFI to trigger the alky pump so everything works more in harmony instead of independent of each other or would this be redundant.
The alky system turns on using a variable voltage from the 3 bar MAP. This variable voltage also lets the system ramp up in pressure.
The XFI output is only on/off. So the XFI output would be like a hobbs switch.
