Modifications makes turbo boost too fast

[cerberusiam]

Am I going to get in trouble if I reiderate what was said by saying that my intake of air is working too well for my current turbo setup?

The problem with this statement is a diesel engine does not work that way. Without boost it will only take as much air as possible to fill the cylinders. It cannot flow too much. When you start boosting then you pack air and the ECU adds fuel based on boost numbers. It only adds a certain amount for low or no boost readings. Put a dirty air filter in and you limit boost which limits fuel hence better mileage.



What you are seeing for boost numbers is not unusual for a system that has no back pressure. The 15 psi at 70 mph is a bit high and would explain lower than normal mpg. I typically run 8-10 psi at 70 and it takes 80 mph plus to hit 15 psi, or weather and terrain. Your boost is controlled by your right foot. Less foot equals less boost. If you want to accelerate quickly you will need to make boost which uses fuel. There is no way around that equation.



The new fuel is more than likely what you are running. It was supposed to be in ALL stations by Oct 15. I find it highly suspect that the station you are using is NOT getting th new fuel, whether they know it or not. The new fuel will definitely impact mpg. I am seeing boost higher by a couple pounds and less EGT's. With the cold weather and winter blend I am not doing much better than 14-15 at 75 mph.



You my have posted it, but, what mileage are you seeing when you think it is bad?



Cheers

 

[SKneeland]

The harder I acclerate from any given speed, my truck produces more boost. It seems you are the only person that is getting that.

of course it does.....



your boost will spike under acceleration, whats the problem?



if im cruising at 60mph, 6psi boost and i mash it to the floor it hits 35psi until i take my foot out of it.



if im at 70 mph & 10psi, the same thing will happen...

 

[bmoeller]

your boost will spike under acceleration, whats the problem?

This is his problem. Needs boost fooling for the ECM. -

At WOT, I peg 35 psi, then my wastegate will open, drop to 25, then hit 30, then drop to 25, the hit 30 again and so on and so forth.

 

[Tryingit]

Could the problem be the wix. Filter. If it doesn't flow enough air won't it cause you to push a bit harder on the pedal and make the turbo work even harder, hence the higher than normal boost numbers. I guess the same would happen if you weren't getting enough fuel. You would have to dig deeper into the pedal to achieve the speed and cause higher than normal boost. I run 70 at around 5psi flat ground and slight hills at around 9psi.



The exhaust and the box alone should not do anything like that. Our turbos are good until 40psi.

 

[bmoeller]

If the air filter doesn't flow enough, the numbers should be lower, not higher.