Robit28 Member 385 Member For: 18y 5m 29d Location: Brisbane Posted 05/05/06 03:12 AM Author Share Posted 05/05/06 03:12 AM The way the xr6t system is set up you will need a retune as the computor control the boost solinord on a duty cycle system and the % of duty cycle will need to be reset to the different actuator.I fitted a new one on my car and with out a retune it would over boost all the time.If you do not want to blow your motor do not do things by half have it retuned.Ian←Ahh, thanks Ian. That's what I was after. Wondered whether the XR6T controlled the solenoid some other way (besides sensing boost pressures). So it controls boost by duty cycle, I wondered whether the duty cycle page within the CAPA editing software was a 'display only' page to show the duty cycle, didn't know if it could be changed or not.Well that answers my question. I think it's a bit stupid controling boost pressures by duty cycle though, wouldn't actual pressures be a more sensible way of doing it? Duty cycles seem to leave you a bit open for errors.Rob. Link to comment Share on other sites More sharing options...
Robit28 Member 385 Member For: 18y 5m 29d Location: Brisbane Posted 05/05/06 03:17 AM Author Share Posted 05/05/06 03:17 AM See what I mean? As RPM increases the boost level will have to drop as more air is being fed (volume) at lower pressure... at the start the wastegate is closed to build pressure quickly, but is opened at the set level to control boost to the desired level, then dropped. If you "need" to drop your boost lower than 12.5psi and you are at 98% duty cycle then there's nothing you can do and you get an overboost condition. The ECU may already be set to drop your boost to say 10psi at higher rpm, so adding the new actuator it can't get it to 10psi and will fault...e are on the same track but... I would get those maps looked at before you give it some at high rpm.←Yeah I do. The only thing I would correct is that to get your boost lower, your solenoid would be at 0% duty cycle not 98%. The higher the duty cycle the more air is being bled and the higher the boost will be.Rob. Link to comment Share on other sites More sharing options...
Paradoxx Colossal Member Member 5,049 Member For: 19y 8m 4d Gender: Male Location: Perth, WA Posted 05/05/06 03:19 AM Share Posted 05/05/06 03:19 AM Sorry, I meant wastegate percentage... inversely proportional I'm just remembering how my last car showed this graphically, and it was wastegate% Link to comment Share on other sites More sharing options...
fill Member 127 Member For: 18y 8m 11d Location: Sydney Posted 05/05/06 04:05 AM Share Posted 05/05/06 04:05 AM This is a great post! I just have one question... Are there not adjustable actuators available, and what is the adjustability for? Link to comment Share on other sites More sharing options...
GOLDIE My new toy Lifetime Members 5,344 Member For: 21y 6d Gender: Male Location: stanthorpe wine capital of qld. Posted 05/05/06 04:41 AM Share Posted 05/05/06 04:41 AM The way the xr6t system is set up you will need a retune as the computor control the boost solinord on a duty cycle system and the % of duty cycle will need to be reset to the different actuator.I fitted a new one on my car and with out a retune it would over boost all the time.If you do not want to blow your motor do not do things by half have it retuned.Ian←Ahh, thanks Ian. That's what I was after. Wondered whether the XR6T controlled the solenoid some other way (besides sensing boost pressures). So it controls boost by duty cycle, I wondered whether the duty cycle page within the CAPA editing software was a 'display only' page to show the duty cycle, didn't know if it could be changed or not.Well that answers my question. I think it's a bit stupid controling boost pressures by duty cycle though, wouldn't actual pressures be a more sensible way of doing it? Duty cycles seem to leave you a bit open for errors.Rob.←The computor sensors boost with 2 sensors one after the throttle body and one before the intercooler so it controls duty cycle using these to values to determan duty cycle.Simalar to injector duty cycle in that the o2 sensor sends a signal to the computor and it controls duty cycle of injectors to make the motor rich or lean.There is a lot of other sensors and calultions involved with the fuel side of things but this gives you the idea how the wastegate system works. Link to comment Share on other sites More sharing options...
F6 UTE - Track Bound EVO III - Member 3,367 Member For: 19y 4m 13d Gender: Male Location: Strapped in and holding on Posted 05/05/06 01:12 PM Share Posted 05/05/06 01:12 PM This is a great post! I just have one question... Are there not adjustable actuators available, and what is the adjustability for?←I have an 'adjustable' 8psi actuator..It's 'adjustable' so you can place the correct amount of 'pre-load' on the flapper/wastegate to suit your own circumstances. Too little, it will 'flap' open under too low an amount of boost, too much it'll overboost your minimum setting.Mine cost ~$90 for actuator and adjustable arm.TurboTech, Great Eastern Hwy.. Link to comment Share on other sites More sharing options...
F6 UTE - Track Bound EVO III - Member 3,367 Member For: 19y 4m 13d Gender: Male Location: Strapped in and holding on Posted 05/05/06 01:24 PM Share Posted 05/05/06 01:24 PM I think you should look at it more from a duty cycle point of view, as this is how it would set the boost... in my previous car it was set as such...1000 - 0%1500 - 0%2000 - 0%2500 - 15%3000 - 65%3500 - 70%4000 - 50%4500 - 40%5000 - 30%See what I mean? As RPM increases the boost level will have to drop as more air is being fed (volume) at lower pressure... at the start the wastegate is closed to build pressure quickly, but is opened at the set level to control boost to the desired level, then dropped. If you "need" to drop your boost lower than 12.5psi and you are at 98% duty cycle then there's nothing you can do and you get an overboost condition. The ECU may already be set to drop your boost to say 10psi at higher rpm, so adding the new actuator it can't get it to 10psi and will fault...I think we are on the same track but... I would get those maps looked at before you give it some at high rpm.EDIT:Also, aswell as the boost maps there will be a "boost limit" which will be set to control the max boost at a given RPM, so if say at 4000 rpm the "max" boost is set to 11psi and your actuator is giving you 12.5 then it will be overboosting and will die. My previous car's ECU was a little more primative and only had a max boost level set overall (one value) which protected the motor at its highest boost point. I would assume the falcon ecu has boost limits set throughout the revv range.←Wait till u get your custom tune done.Then you get Throttle Position Vs Boost + RPM.10% throttle 50% Boost20% Throttle 80% Boost30% Throttle 100% BoostEffectivley ~halving throttle distance.etc etc etc... hence that squirt the throttle and BANG, off she goes.. Not entirely reflective of the cars power, you just don't have to put your foot to the floor ( I think factory is 80% throttle position 100% boost or something ) Oh, after fitting my actuator, boost changed rather dramatically.I could turn the tyres in 3rd at 60kph. But 100% load, it pinged. Part throttle was a Porsche Boxter 'S' destroyer.. All beacuse of throttle position Vs boost.. Link to comment Share on other sites More sharing options...
Ralph Wiggum Moar Powar Babeh Lifetime Members 19,323 Member For: 18y 7m 5d Gender: Male Location: Perth Posted 05/05/06 01:41 PM Share Posted 05/05/06 01:41 PM I'll be intersted in this as well, as I am considering changing the standard actuator to one with a higher opening pressure.I'm chasing high kw numbers, and expect poost to be reasonably high when my engine is complete, and I'm wondering if the standard actuator is up to the job.Anybody have any experience?Any suggestions where to get a good replacement actuator?←Hey Ninka whats Poost....... hehehe sorry couldnt help myself... Link to comment Share on other sites More sharing options...
Xtreme F6 Team Xtreme Donating Members 1,680 Member For: 19y 2m 20d Gender: Male Location: Perth Posted 05/05/06 02:00 PM Share Posted 05/05/06 02:00 PM I'll be intersted in this as well, as I am considering changing the standard actuator to one with a higher opening pressure.I'm chasing high kw numbers, and expect poost to be reasonably high when my engine is complete, and I'm wondering if the standard actuator is up to the job.Anybody have any experience?Any suggestions where to get a good replacement actuator?←Hey Ninka whats Poost....... hehehe sorry couldnt help myself... ←your a bloody shocker Link to comment Share on other sites More sharing options...
Ninka Donating Members 1,850 Member For: 21y 4m 5d Gender: Male Location: Perth, WA Posted 05/05/06 02:37 PM Share Posted 05/05/06 02:37 PM I'll be intersted in this as well, as I am considering changing the standard actuator to one with a higher opening pressure.I'm chasing high kw numbers, and expect poost to be reasonably high when my engine is complete, and I'm wondering if the standard actuator is up to the job.Anybody have any experience?Any suggestions where to get a good replacement actuator?←Hey Ninka whats Poost....... hehehe sorry couldnt help myself... ←What, you have never heard of Poost!!!! Blo*dy aussies, only know one language Link to comment Share on other sites More sharing options...
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