What is turbo surge?

[DevenWood]

I'm pretty sure I understand turbo lag and turbo bark. But I'm not sure I understand turbo surge. What is it? At what rpm dose it occur and why? What are some fixes?

 

[Idaho CTD]

Typically it when you try to "over air" the motor. Diesels dont need a specific air to fuel ratio like gassers but they will only accept so much air at any given time. Once you go past that point it tries to stall the compressor on the turbo. It's quite common with large compressor turbos and is worse when towing. The easiest fix is to keep rpms up or to go up in turbine housing size.

 

[DevenWood]

I hope my sig. shows up this time.



So is it possible to experience turbo surge with a stock turbo? Thats all I have, and at moderate RPM with the TST on 6/6 or7/7 I get what sounds like turbo bark but I never let off the pedal. I also see a sudden drop in boost according to my gauge.

 

[Devan Manis]

there you go thats compressor surge. in addition to Idaho CTD compressor surge is when there is not enough air flow for a given boost pressure, the pressure tries to come back out through the compressor and thats where the "bark" comes from, and turbo bark is compressor surge as well. Ohh and fixes are better mass air flow through your motor, exhaust, intercooler, intake,anything that improves air flow through your engine. The rpm at which it occurs is different from differnt size turbo's and setups.

 

[DevenWood]

Thanks for the info.