Diesel Insights: Towing in the race tune

[ShinerBock]

This is a great video the guys over at Duramax tuner (aka Calibrated Power Solutions) talking about towing with the high 500 RWHP tunes on modern diesels trucks. Personally, I don't like to tow anything over 7K in my 500+ RWHP tune even though I probably can with the built trans. I usually switch between my 450 or 400 RWHP tunes as needed when I am towing over 7k.

It also touches on some of the de-fueling/pull timing parameters built into the stock tune of Duramax's that will lower power output similar to what I said happened in the Freightliner vs Duramax Ike video. All of the diesel manufacturers do this although some don't need to cut fuel as often or as much since they don't advertise such high power levels to begin with and like to advertise more conservative sustained power ratings. Basically, some may advertise the best their engine can achieve in perfect scenarios at sea level and will reduce power as barometric pressure increases(go up in altitude). While others may advertise what you will get all the way up to say 10k elevation.

So just because that new diesel of yours says it makes 440+ hp at sea level, does not mean it is able to make that all the time and the nannies built into the programming will cut power to keep you from harming the engine. As they say in the video, this could clearly be seen in aftermarket gauges like the EDGE CTS2 monitor because you will have less fuel pressure available.

DIESEL INSIGHTS: TOWING IN THE RACE TUNE

[twodownzero]

My concern isn't the engine anyway, it's everything else. Doubling the torque output is going to be really hard on the drivetrain, and doing so with 10k pounds behind me even more so.

[Grit_dog]

Right, my truck doesn't have a "race" tune. It has a Crazy Larry tune, lol!
(Shows you how cheap, old and poorly tuned my truck is....)

[ShinerBock]

schlep1967 wrote:
Now why would anybody tow while racing? I ask because we all know it says right in the instructions that that tuner with "race" as a setting, is only for off road use......

Most diesel tuners have gone away from calling them race tunes and just started calling them max effort tunes or by the amount of power being added. Terms such as "tow", "street", and "race" are mainly used for the "not so smart" people they talk about in the video who don't know when to back off or what supporting mods are needed for each power level. You can use any power level on the tune, just as long as you have the right supporting mods and know what parameters to watch.

A tuned truck is not for everyone. Most people like it dumbed down for them so that the vehicles does everything with all its nannies to keep them from harming their truck. As I said before on this forum, tunes are for those who know what they are doing and prefer to be the deciding factor when to lift, not the computer. The higher in power level you go, the more knowledgeable you should be.

I liken towing with a tuned diesel to that of the old semi's. Truckers back then had to keep an eye on a whole dash full of gauges, and a good trucker knew when to back off or when he a lot more to go based on his gauges. If that is not your style and like the computer to do everything for you, then I would stick with a stock diesel.

[ShinerBock]

philh wrote:
OEM's spend miliions upon millions of dollars calibrating the powertrain to achieve customer satisfaction, EPA requirements, and component longevity under a large variety of conditions.

That is the whole point of custom tuning. The OE's mapping is generic made for a variety of situations and scenarios many of which you may not even use your truck in. You may only tow 12k in 70F weather, but you have the same mapping of someone who tows 23k in 100F. With custom tuning, you can map the fuel and shift strategy specifically to how you use your truck. You can also shift to higher power levels as needed .

I can go for a 390 RWHP all the way to 500+RWHP by turning a my 4 selection CSP switch that is right below my steering wheel. Although my 500 RWHP at 2,800 rpm tune makes the same 330 RWHP that the stick tune does at 2,800 rpm, but just at a much lower rpm around 1,700 rpm. This means I don't have to down shift and can stay in a higher gear at a lower rpm more often which conserves fuel.

philh wrote:
tuners either stock or custom tunes, use either a set of assumed conditions or in the case of custom tuners, the atmospheric and fuel conditions for that day.

That is false. Fuel mapping doesn't work that way.

[schlep1967]

Now why would anybody tow while racing? I ask because we all know it says right in the instructions that that tuner with "race" as a setting, is only for off road use......

[philh]

OEM's spend miliions upon millions of dollars calibrating the powertrain to achieve customer satisfaction, EPA requirements, and component longevity under a large variety of conditions.

tuners either stock or custom tunes, use either a set of assumed conditions or in the case of custom tuners, the atmospheric and fuel conditions for that day.

Max HP tuning is awesome, but I can't even count on one hand how many times I've ever gone WOT at max RPM while towing a trailer.

YMMV

[ppine]

Don't use a race tune. Use a towing tune.
Heat is the enemy when towing. Give your self the best chance by using towing mode.