snowmanx

Gettina boost foler for my 05 truck. Running a smarty, and my understanding is that increase boost will help to lower the EGTs? Not sure I understand this.

When I turn up the boost on my snowmobile, with no other changes, I would burn it down, as more O2 = hotter egts.

Does the ecu on the truck automatically increase the fuel? Adding air without fuel normally increases temps...what am I missing here?

Thanks for any info

CamperAndy

You have to leave gas engine theory behind.

The diesel engine will only make as much boost as you have fuel for.

rip 112

Well in your case the he351 has a little more efficiency left in it over stock. Basically Cummins and Dodge have to tune these trucks to meet strict emissions and make the truck as reliable as possible. The stock programming yielded the best mileage around 25psi. When you add additional fueling you are creating a scenario to make more boost naturally by volume. In this case egts can become hotter with more fueling because there is not enough boost to evacuate the gasses in time. Adding a boost fooler will allow you to achieve more boost without causing overboost codes and in turn accommodate moving more air through. The Smarty with timing also cools egts down internally allowing for lower egts overall.

tesla440

Forgive me RIP, but I thought that increase timing was a trade off from less EGTs outside, to higher inside the cylinders to extract more energy.

rip 112

I'm just speaking from my own experience with my truck, with no timing it ran hotter, but with added timing egts were noticeably cooler all around, but especially up top. These trucks are known to like more timing. But I also know this has been said more for the 03-04s also.

ratsun

Doubt you need a boost fooler for just the smarty, it should do it for you up to 40 or so psi ( my 03 goes 45psi with out a CEL) and its only going to stop the CEL from coming on not give you any more boost.
Gas engines lean = hot
Diesel engines fat = hot.
Your sled would be running lean with more boost and no added fuel = bad
Your Cummins is already fat with the extra fuelling from the smarty so extra boost is generated to cool it down. The boost is generated by the fuel (heat) spinning the turbos turbine so more fuel = more boost up to the limits of the WG or turbos capability to produce boost (map).