Ok I am new to turbo trucks but have turboed snowmobiles before so have an understanding how the system works but confused tuning for trucks. If you tune let say 4# of boost and go to 8# will the ecu compensate or have to retune completely with more boost. Looking at efi live or hptuners. I live in northern Minnesota so there is no tech support to go to. So would like to know best way to tune for boost.

Truck being turboed
Chevy silverado 2009
Hd 2500 6.0

 

Welcome to the forum!
I have a turbo M8 153, so you are in good company

Your truck should be tuned to calculate the mass of air in the cylinder so it can the injector cycle to deliver the appropriate amount of fuel. For instance, on the dyno, a tuner will be able to accurately hold your engine at particular load points through out the rpm range and measure the amount of air your truck is pumping (volumetric efficiency). Your pcm (powertrain control module) is overwritten with the new data so it can calculate accurately for your given arrangement how much air is actually making it into the cylinders throughout the range. For areas of the VE map that a tuner can't produce to measure, the data is interpolated so that if for some reason you were to hit that point (i.e. by increasing boost pressure) the map would allow the pcm to estimate the amount of air. Usually it is estimated on the safe side so the PCM thinks there is slightly more air so that it adds more fuel as opposed to less. This is assuming the MAF sensor has been removed, although regardless the VE table should be updated to reflect the engines ability to fill the cylinders.

Also keep in mind that boost pressure is simply resistance to flow and not actually a measurement of airflow.

You going to Hay Days?

 

The pcm should be tuned to the maximum desired/allowed boost in accordance with wastegate setup. On my old 05 2500hd turbo truck I was tuned to 14lbs of boost using a MP70mm, but in use of wastegate spring only, I was always limited to 7-8lbs of boost with no issues. I used the smaller turbo for instant spool and kickass tq for towing

 

thanks for the information!! Which would be better to tune with efi-live or hptuners? Or is that just personal preference?

And yes I will be going to Hay Days. Be there friday evening some where around 7-8 ish.

 

Sweet I'll see you there, I'm usually a vendor but this year I am just going to do the swap. Have an enormous amount of cleaning out to do, I have a 12 cat on order so have to get rid of 2 sleds and all the spare parts.

I have EFIlive, I would assume either could do what you want but I like mine so far. You will probably get different opinions, you may want to go with the same software that the person ultimately tuning your truck uses. I assume he would use your license to tune your truck and then you could edit it and make small changes without having to book an appointment every time.

EFIlive lets you download a full featured demo version of their software, the "Scan" software program for logging data, reading and clearing dtc's and many other features and the "tune" software that reads, edits and flashes the program into your trucks pcm. You need to buy the software though to actually connect it to a vehicle, it comes with a handheld scanner and cords that connect your pc to the vehicle.

 

Both softwares will do essentially the same thing. I would recommend finding a reputable tuner close to you that can get you going. The software can be a bit overwhelming when you first begin using it, and a turbo truck isn't the best place to begin your learning curve lol. If your satisfied with your tuner by the software he uses to be compatable, and you can slowly learn and make adjustments on your own. I own efi live but I will say that there is much more beginners support for hp tuners available, just something else to consider