Turbo boot

[MA2LA]

I was bsing with a fellow cummins nut who has a 04. 5 and had a 92, he also is an owner operator and wount buy anything unless it has a cummins in it. In discussing ways to get more power he asked if anyone had been wraping the down pipe and putting an insulated boot over the turbo. many of the bigger trucks seem to do it and on his pete he saw better power and performance. the only thing i can think of is simliar to caoting headers for gassers and picking the right size exaust for them is that that if you keep the heat in the exaust gas it will keep it velocity up and provide better exaust scavaging. but thats just a guess. what ya think?

 

[Bob4x4]

I have done this on a few trucks including my 94. I never did any before and after testing but I know my engine compartment is cooler as well as the floor. It may have also dropped a little noise through the down pipe. On of these days I will have to pull off the header wrap to see if it has affected the turbine housing and or pipe.



Bob

 

[jwgary]

I don't know if you would call it scavanging, but I could maybe see an advantage. At first I thought it would cause more backpressure since the pressure would decrease as the exhaust cooled. I would guess, however, that the pressure differential from the turbo exit to the pipe exit is not very much. Since a hot gas takes up more volume the velocity of the gas would increase. This could cause more back pressure since you get greater viscous drag from the inside of the pipe at higher velocities.



The greatest advantage would be to wrap the exhaust manifold BEFORE the turbo to keep the EGTs as high as possible to give more energy to the turbo. All of this is minimal since heat transfer is a very slow phenomenon compared to what is happening in the exhaust flow. I don't really know that you could actually measure the effects.