Boost control

[Diesel Dragon]

Hi Everyone

I was out today looking around under my hood and I noticed that the turbo wastegate is controlled mechanically by a hose from the outlet (pressure) side of the turbo. I thought these new Duramax's turbo boost were computer controlled. Guess not. If there not, then what do all these power enhancers like the Juice do to increase power just add more fuel? I thought it would be a big benefit for power to add more boost too. Has any one tried experimenting adding more boost? :confused:

Diesel Dragon

[mackin]

Some of us have plugged the Wastegate.....Not me of course.....

Performance gains, minimal at best....

Lower EGT'S ya I believe so......

The million dollar question as asked before is exactly what your asking......

"I thought these new Duramax's turbo boost were computer controlled. Guess not. If there not, then what do all these power enhancers like the Juice do to increase power just add more fuel?"

Stock boost is 21 pounds or so.....With the Juice some have reported 28 Pounds of boost, no wastegate modification.....So if the bleed off mechanically is set for 21...... :confused: :confused:

I can register 32 pounds of boost,wastegate deprived with modified air intake......

Computer and sensor must play a part somewhere.....

Area 51 ring a bell on this subject ???? Martians ??

MAC :D :D :D

[Geerrhead]

Guy's maybe I could help explain this. ;)

The juice box adds fuel as well as timing to increase power. More fuel, means more heat. More heat spins the turbo faster, which mean's more boost!

Most people think that exhaust air blowing thru the turbine, spin's the compressor wheel. While this is true, there is also a scientific explanation as well. I'm not a rocket scientist, so bear with me. I'll explain in my laymen's term's.

I recall my teacher saying you can only convert energy. The diesel fuel is being converted into heat, during the combustion process. The resulting exhaust gas, is hot. As the exhaust gas expand's, it convert's it's energy to spin the turbine in the turbo. The turbine spin's the compressor, which builds boost. The hotter the exhaust gas, the more kinetic energy in the expanding exhaust gas, which makes more boost.

If you spend some time around performance turbo application's, you might see some attempt's to keep the heat in turbine. Examples would be an insulated blanket around the turbine housing, coated or wrapped exhaust manifolds, etc. By increasing the temperature of the gas reaching the turbine, there will be less turbo lag.

I hope this helps. smile.gif

[a64pilot]

TST provides a new boost hose with a calibrated leak with their Powermax fuel box. It increases the boost from a stock 22-23 lbs. to around 30-32 lbs. I believe it is done to help control EGT's although there is an increase in power also.
Apparently 30-32 lbs. of boost is about the efficency peak for the stock turbo, any higher and you are heating the air more than compressing it and even though the air is at a higher pressure, air density is lower.

[Kennedy]

FYI, there's a "sweet spot" for every turbo. When we start to bear down on the wastegate, we will come to a point where it adds say 5 psi of back psi and 1 psi of boost.

At present, I have seen 45 psi back psi and 28 psi boost at upper rpm's. In the "sweet spot" which is when you roll into it (at say 60mph locked in OD) the boost will get out in front of the back psi. This is why the truck (when chipped/programmed) seems so much better when you can hold OD.