Paccar MX-13 tuning

[Texasdude74]

(06-03-2017 )Black sheep freight Wrote:  Did anyone make it any further with this, I just a bought a 2015 t680 mx-13 485hp, that's crying out to be liberated from the mandate B.S.

If anyone has I'd be interested to know the results.

I now know several people that have fixed Paccars. But not by anyone on this board. I believe Unilever may have some options for them but I'm not certain of this. Last I heard Gearhead was working on it but wasn't 100% there yet. I'd contact Gearhead first since it was his tune that led to the first (and still only) common rail ISX powered car carrier to reach 400k miles on one engine and then 500k miles, truck currently has 563k and hopes to be the first to crack 600k! Truly uncharted territory. 300-400% durability improvement.

If you're going to do it, stick with VGT. Guys that have converted to old school turbo report their jake is about equal to ISX on first setting. I don't think I could live with that.

It's hard for me to adapt to recommending a smaller motor. My entire life I've subscribed to the theory that there is no replacement for displacement. Hardcore big block guy I've always been. But, in the turbo world all that really matters is can you spool a turbo large enough for your power desires at an engine speed you can use and will the bottom end handle that power. Variable geometry turbos and common rail fuel systems make it so much easier to reach a given power level and rpm with a smaller motor. In the 500-600 horse power and 1850-2050 torque range 15-16 liter engines are really no longer necessary. In fact, if you have to shorten the deck height, rod length and piston compression height to fit a 15L engine in a modern aero truck, you can make an honest argument that the larger motor is at a clear disadvantage.