kjm

I design control systems for John Deere. Theings like auto height control for combines and auto track systems that allows the operator to plant cane with gps and the following year harvest using the gps data. So I decided to design a boost controller for myself. I'm using the John Deere ecu which has 30 inputs and 20 outputs. So as of now I'm reading the following

Boost psi
Fuel psi
Gear selector on trans
Before and after intercooler temps
Transbrake on/off
Front wheel speed
Rear wheel speed
Coolant temp
My question is what would be the best system to control traction and
Get the fastest 60' and et. I'm thinking 3 designs

1. Standard boost control based on time and also using wheel speed comparison from front to rear for a secondary control. So time based boost chart and if it sees wheel spin it will reduce boost until wheel spin is gone. Not sure if hen the wheel spin comes in should the power be reduced through wastegate or should I pull timing to have a quicker response ????

2. Would be just leave wastegate with high pressure spring and control traction through timing when wheel spin is detected???????
3. Is to just run a electronic controlled dump valve in the charge pipe and let the turbo spool and just dump boost to atmosphere to control launch boost and then plot time based pressure map for the run and control traction with dumping boost with the proportional dump in the charge pipe or control traction with timing curve dependent of wheel spin sensors ???????

I know that the turbo could over speed some by dumping boost at charge pipe. But this would be only activated for 1/4 mile passes. The rest of the time and normal street driving would control boost with wastegate and comparison of front and rear wheel speed sensors.
Any thoughts would be greatly apreciated. I'm also thinking I can use this to add traction control to a stock ecu. By reading in the coolant temp into my ecu then sending out signal to the stock gm ecu. When the traction control is not active. I would just read in the coolant temp and send the exact data to the gm ecu. How ever when the traction control is turned on for 1/4 mile pass I could read in coolant temp but as wheel speed sensor show tire slippage I could send some predetermined high values like 5% wheel slippage would send gm ecu 250 degree coolant temp and 6-8% would send gm ecu a coolant temp of 275 degrees and the tuner could set his tune to pull a given amount of timing for 250 degrees and pull a more aggressive amount for coolant temp of 275. And this would reduce power and recover wheel spin and then my ecu once wheel spin is below the parameters would start back sending out the true coolant temp and gm ecu would return to standard timing

Any thoughts would be greatly appreciated. Nice part is. I can read in any data compare it. Do math channels with two or three or multiple inputs and send out a control to a valve , solinoid or anything like that.

Kerry

Sleeperls

I just want some john deere goodies. Ill be following this since im a farmer.

flyingbrick88

Why? Lots of electronic boost controllers available cheap already- and most aftermarket ECUs these days are able to do it.

If just for personal DIY gratification then AWESOME. I think biggest hurdle will be the software and programming interface so that its functional

kjm

The software and programing is easy. I have many closed loop control circuits running on many combines and harvester. I want to design it the way I want it. I'm also working on an electronics wastegate that I Wil control with this system so no CO2 or solenoids just a electronic actuator that will do what I want when I want lol. My big question now is. Can reduced timing alone be enough to stop a turbo charged cars wheel spin? Or will boost need to be reduced????? I'm also using this system for data logging runs, turning on fuel pumps and lights , watching afr data, personalized dash with speedo, trip resets, fuel level, tach, shift points and lights and activating meth by boost and temps.

ironhorse583

iTrader: (5)

bump this up...give the man some info...

stevieturbo

Whether timing along will reduce wheelspin is very dependent on traction vs power.

If I made 2000hp and running on asphalt or concrete...then no, timing will never reduce power enough.

If I made 500hp, on same surface, then very easily timing would be enough.

Pulling timing is the fastest way to respond to excess power, after that killing either fuel or sparks per cylinder to reduce power. Beyond that you could use boost I guess, but boost control for that would be very slow by comparison.

Likewise venting boost pressure would be a slow response to excess power. But I'm sure they could also be used to some effect.

kjm

Thanks for all the thoughts and comments. Not trying to save money or reinvent the wheel. It's just that I'm using this system to control and display other data so I might as well use it for a custom boost control.
Thanks again and any more comments are welcomed

koolrayz

iTrader: (26)

Big stuff 3 pulls timing to reduce wheel spin

kjm

Thanks. I think I will start with a time based / gear based boost map and if wheel spin accurs I will try pulling timing first and se how that work. I will change the time based boost targets if wheel spin remains but if it accurs in a run I would like to try and salvage the run by reducing timing when wheel spin is present. We are planning on campaigning this car around the south louisiana area street scenes

ls1_chevelle

iTrader: (9)

If you want to become rich and throw a controller my way for testing... lol. you need the boost controller to control boost based on wheel speed/driveshaft speed and/or front vs rear wheel speed(doesn't work well when a wheelie comes into play but for the majority of street car it will work awesome).

A guy will have more control over getting the power down with boost than he will with timing.

gpr

iTrader: (6)

I was literally just thinking the other day how I should build something exactly like this. Control wheel spin based of the front and rear wheel speeds to get max traction and power to the ground. Only side affect is wheelies will make the car pull power....

Like mentioned above timing is the best and quickest way, but can only pull so much power. Controlling boost would also work but is slower response. If you could control both and have them work in conjunction this would be a sweet system. I think i would control boost by leaking it off the bov instead of trying to control the waste gate. Keep the turbo spooled that way when you regain traction you can slowly close the bov and your boost will be there instantly.

kjm

Yea I was kind of thinking wheelie would throw things off, I have been writing software to look at rate of rear wheel speed increase. I can allow a given amount of speed increase at rear wheel per millisecond and if it increases faster I can consider that wheel spin.

asubennett

iTrader: (6)

Search "skinnies" set up. He has his dominator controlling boost based his front wheel speed sensor. Very effective.

If you could some some combination of time based boost initially that changed to the front wheel speed sensor after say 2 seconds that would ideally eliminate the wheelie issue at the track.

kjm

Yes that is very doable. I have a state Chanel that changes the control state depending on your predetermined parameters. So the state of control can go from time based to wheel speed or from time based and if wheel spin accurs it can swap to wheel speed control and back to time base after wheel spin has been eleminated.

You dream it and I can program it into this Ecu and it has a nice 5" display that can be set to display any inputs or outputs in any way we see fit

Very nice ecu. I use it to control auto steer on johndeere harvesters. All closed loop and the harvester drives itself without an operator.

I just need to figure out what I want to control and how and when I want to control it.
I have a launch boost that is turned on with transbrake on. Or foot brake and when released the timer starts and every .500 ms you have a target boost up until 10 seconds. Now I just need to decide if I dump boost at charge pipe to maintain turbo speed and get instant reaction? Or if I just control my electronic actuated wastegate to control boost

If you guys have anything you think ams, boost leash or any other boost controller should have that they don't. Let me know. I would like to try some new options dream it and I will see if I can make it happen

stevieturbo

Using boost to prevent wheelspin in the first place yes.

But as a reaction to wheelspin, boost control will be very sow compared to timing.

You could use boost control secondary to timing though, if timing wasnt sufficient then you could try pulling boost.

Really though, a decent standalone ecu will already do all these things in one package.

Not quite sure how he's going to interface an external controller to have proper control over timing in order to reduce it, or cut cylinders if need be for a power reduction.

kjm

I set my coolant sensor as an input to my ecu and sending out a coolant signal from my ecu to the gm ecu. Then create a coolant map that will reduce timing depending on sensor temp

Something like this

My ecu alters coolant temp when it sees wheel spin. So maybe 1-3 % wheel spin equals coolant temp of 230. And my tune will have coolant temp 230 pulling -5 timing. And then wheel spin of 5-7 would send coolant temp of 240 which my ecu tune would be set to pull timing back another 8 degrees of timing. As wheel spin is reduced my ecu will return to delivering the exact coolant temp that the sensor is seeing and timing returns back to standard timing map
Of course these values are just examples