Nissan Titan XD Forum banner
1 - 3 of 3 Posts

·
Registered User
2019 Titan XD Pro4x Cummins
Joined
·
800 Posts
Anything that blocks or redirects coolant flow might be a problem. Wouldn’t want one head to have a hot spot from coolant deadheading.
 

·
Registered User
2019 Titan XD Pro4x Cummins
Joined
·
800 Posts
Higher engine temperatures are important, for efficency and to help prevent fuel from condensing on the cylinder walls.

Most of the deleted trucks are running so lean there is actually risk from the diesel flashing. More fuel you add, the worse that risk gets.

The Isv is averaging 10-15psi more boost than it needs for a good fuel air mixture.
 

·
Registered User
2019 Titan XD Pro4x Cummins
Joined
·
800 Posts
Lmfao how are we running lean when we barely touch the pedal and it’s dumping smoke out, that’s extra I burned fuel, I promise I’m not lean.
You do understand there is a difference between acceleration and the engine being under steady load right?



If you look at the "Boost - Stock" tab of this sheet, I have done a loose calculation of the fuel air mixture according to mass air and fuel consumption on the bottom table. The numbers are certainly very rough as I I'm missing a lot of datapoints, such as compressor efficiencies. Anything larger than 0.0625 is richer than an ideal stochiometric afr of 16:1. Supposedly Cummins likes 14.4:1.

For the vast majority of the engines operating range, and where you would actually be using power, the engine is running extremely lean. To run this lean, it takes a fair amount of energy to maintain that boost request. That's a cut and paste of the stock table. It's requesting almost 3.5psig of boost at idle. That means the rotary valve is clamped right down. This is happening with most, if not all of the delete tunes and why they exhibit such obnoxious turbine noise in the exhaust.

The map I'm currently running is on the next tab, however it has a host of issues I haven't resolved yet.
 
1 - 3 of 3 Posts
Top