Tuning tips for a 2005?

[Firebirdjones]

I've had good success tuning our LS engines but completely new to the diesel world. I've been reading the small list of tuning help here in the diesel section but I'm still a little fuzzy.

I live in mountain terrain so that is a concern. I also occasionally tow a 10,000 lbs. enclosed trailer 2-3 times a year. Otherwise it's much smaller stuff on occasion, but primarily used as a empty driver 90% of the time. I don't know what a safe tune would be. I've read some suggest 10% increase in fuel and boost, others 20%.

I'm looking for a mild increase in power, decent fuel economy, on an otherwise stock truck that will have a turbo back exhaust and free up the air intake. I'm also running 33" tires. I'm thinking the 10% increase would suit me fine if it's safe to pull with.

Anyone that may have suggestions as to what is safe to change or lead me in a direction to take, or something to start with would be much appreciated. It's a 2005 LLY 4x4 crew cab. Thanks.

[sarg]

You are in about the exact same place I am, lol. I have pretty much determined I am going to add a lift pump and aux better filters and call it a day. But then I am looking for longevity. Seems gains are pretty easy, but at the potential expense of the transmission if you go too big.

[Dashman]

I'll share with you guys what I have done. I start off by copying with labels from the pulse width table into a spreadsheet. I paste the stock PW table into 3 different sheets. Delete the values only from the 2nd and 3rd sheets. Use the second sheet to enter in scalars (or multipliers). The 3rd sheet becomes your new PW table (value from first sheet multiplied by the scalar from the 2nd sheet). 30mm^3 gets reduced from 1 down to .95 at the least, and increased to 40% at the maximum. The incremental increase gets calculated from the differences (1-.95) or (1+.40) divided by the number of cells. For what you want to do, 20% would be fine. I've hauled beyond 20,000lbs with no problems. I cap out the lower pressure at a fixed 4200 usec where it was 3900 stock, and taper down to my new high pressure PWs. [In hindsight, it doesn't really matter what happens below about 90Mpa, so just use the stock values.] Use the same scalars per mm^3 to increase your boost pressures to match your new fueling. Use the timing calculator to adjust the timing for a few different ranges of mm^3. I start with as much as 54% and end with 44% or so (BTDC). [At lower fuel, you can be much higher than 60%. At higher fuel, you can be above 50%. As long as you don't exceed 30 degrees.] You'll need an EGT gauge for sure. When I have my 40% tune loaded, I'll spike EGTs to 1200 in no time. In this tune, I realize that I'm commanding too much boost, and timing is at 47% on the top end. Anyway, increase shift points, slightly, will help with mileage also. The biggest thing to protect your transmission is to get comfortable with the torque management quantity tables. I set up a scan config file to chart the main fuel with rpms and drivetrain torque. It'll show you where and how much fuel difference is happening at the shifts. You don't want a surge, but you don't want slippage either. If you make a tune that's not what you like, just don't keep loaded for too long, and you'll truck will live through it, hahaha. Good luck guys!