SparkFun Forums

[Dubbs_]

I want to build a VGT Controller (Variable Geometry Turbo) The VGT I have is controlled by PWM. I want to build a controller that takes information from the CAN on my truck and use it to build a map to control the VGT.
My problem is... I'm a newbie. (Feel free to harass me about it). I'm by no means the caliber of hacker most of you are but for some reason this stuff gets me all sorts of excited. From reviewing the products available on this site I think it's doable. But, to do so I'll have to do a little studying. What do you seasoned vets think? Is this doable? Or do I have a pipe dream here?

[lyndon]

It's doable and seems like fun. I did a lubrication controller for an RX-7 once, but I would get a spare truck to test on

Screwing with the turbo on your daily driver, esp. if you have no experience is not very wise.

[Philba]

Yeah, it sounds doable though there may be issues of response time - reading data and getting the VGT to respond may have some lag.

I assume by CAN you mean OBD-II. You can get data via an OBD-II connector. I'd suggest an arduino as the controller since it supports PWM directly. I'm not sure how to actually get the data into the arduino but it's probably not difficult. There are also high resoulution PWM libraries that support better than 256 PWM steps if that's needed. For controlling your VGT, you'll want to understand PID. There are several PID libraries that you'd want to look at.

[Dubbs_]

Yeah, it sounds doable though there may be issues of response time - reading data and getting the VGT to respond may have some lag.

I assume by CAN you mean OBD-II. You can get data via an OBD-II connector. I'd suggest an arduino as the controller since it supports PWM directly. I'm not sure how to actually get the data into the arduino but it's probably not difficult. There are also high resoulution PWM libraries that support better than 256 PWM steps if that's needed. For controlling your VGT, you'll want to understand PID. There are several PID libraries that you'd want to look at.

Good idea on the response lag...

Yes OBD-II

I'm looking in to those arduino controllers...

I don't know PID... I hope he is nice... Lol

It's doable and seems like fun. I did a lubrication controller for an RX-7 once, but I would get a spare truck to test on

Screwing with the turbo on your daily driver, esp. if you have no experience is not very wise.

Yes baby steps... Once I have the VGT installed on my truck I can just lock the fins in any position I want so I could drive my truck still.

The VGT I have is off of a John Deere tractor and I just happen to be a tractor technician for JD. Next time I have one of these tractors with this VGT I can look at what range of PWM is being sent to the VGT and all kinds of cool stuf with my laptop while its on a dyno.