Paul M Posted November 23, 2013 Report Share Posted November 23, 2013 Looking to vary boost pressures down a drag strip Most use the timed approach but I'd like to have the boost vary based on driveshaft rpm or wheel speed/rpm I have the driveshaft input rpm set as DI 5 and while setting the 'wastegate %DC1' table x=rpm and y=speed DI 5, the speed DI 5 would go to a maximum of 400. What units are these rpm or km/h? Any ideas on the best way to set this up or an alternative method to vary boost pressures down a drag strip?  Thanks in advance Paul Quote Link to comment Share on other sites More sharing options...
Fredrik Pettersson Posted November 24, 2013 Report Share Posted November 24, 2013 Speed is meant for wheels iirc(km/h) beware that just using rpm vs ds rpm will allow you to over boost the engine. personally I would set up the boost table to be as good as possible and then retard ignition based on di5 frequency. hope it helps Quote Link to comment Share on other sites More sharing options...
Kelly Gordon Posted November 26, 2013 Report Share Posted November 26, 2013 You need to look in the help file on how to scale a speed inputs. The max frequency input into the Link is either 400 or 500 Hz so you need to choose the appropriate tooth wheel that will keep you under that Hz limit at full speed. If the frequency at full speed is less than the limit you can scale the input however you like and use that value in your tables or you can use raw frequency but that doesn't correlate to rpm, kh/h, or anything, its just raw counts. Have you thought about using vehicle speed as an axis on the table   Previously Paul M wrote: Looking to vary boost pressures down a drag strip Most use the timed approach but I'd like to have the boost vary based on driveshaft rpm or wheel speed/rpm I have the driveshaft input rpm set as DI 5 and while setting the 'wastegate %DC1' table x=rpm and y=speed DI 5, the speed DI 5 would go to a maximum of 400. What units are these rpm or km/h? Any ideas on the best way to set this up or an alternative method to vary boost pressures down a drag strip?  Thanks in advance Paul Quote Link to comment Share on other sites More sharing options...
Stevieturbo Posted December 5, 2013 Report Share Posted December 5, 2013 Undriven wheel speed would be safer, so you would never experience an overboost with wheel spin scenario. Assuming the car doesnt pull wheelies of course. Quote Link to comment Share on other sites More sharing options...
Fredrik Pettersson Posted December 10, 2013 Report Share Posted December 10, 2013 Paul ; switches on the festbord sounds like a viable option , another option is to set up wheelspeed sensors and use %slip to limit rpm(dunno if it's usable for boost control , you would need dual boost maps with the second as overlay though so you can have %slip vs rpm vs map ) Hope I don't confuse  you , there are a lot of ways to do this Quote Link to comment Share on other sites More sharing options...
Paul M Posted December 12, 2013 Author Report Share Posted December 12, 2013 Fredrik, Can't use traction control here in Australia. That's the regulation ANDRA has placed I plan to run a wheelspeed sensor on one of the rear wheels instead of driveshaft speed, as I believe I can utilise this input for more functions Probably have boost control based on gear instead of km/h, would be more consistant I'm noticing there are lots of ways to do this Would love more boost tables instead of 3 max, got one dedicated to just the launch Appreciate your input   Quote Link to comment Share on other sites More sharing options...
Fredrik Pettersson Posted December 14, 2013 Report Share Posted December 14, 2013 Aha I see boost by gear is effective and simple so it's Worth a shot let us know how it turns out Quote Link to comment Share on other sites More sharing options...
Stevieturbo Posted December 15, 2013 Report Share Posted December 15, 2013 For dedicated drag use, then a timed approach will probably be better. There are obviously reasons why most controllers in the drag world use it. With the timer activated once the vehicle is moving. or if there is a way you can use GPS to provide a speed signal that would be reliable Quote Link to comment Share on other sites More sharing options...
Paul M Posted December 16, 2013 Author Report Share Posted December 16, 2013 Fredrik Thanks will do when it gets going Still looking at my options Got 4D igntion map for 1st and 2nd gear to reduce timing 2 boost tables, boost on the start and boost settings for the actual run for each gear Got plenty of additional speed and travel sensors for logging Should be fun  Stevie Timing is mostly used but so many things can happen between these points that would make your run inconsistent Timer switching would require dual switches, one for the clutch and a secondary switch GPS would be great where you're able to tune to specific sections of the track. Would be expensive for the sensor and can the link facilitate a GPS sensor? Quote Link to comment Share on other sites More sharing options...
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