Turbo Sweet Spot

[boostmaster]

This may be a stupid question but when talking about the sweet spot on a turbo in what part of the run is this referring to. 1st - 2nd or third gear at full boost.

 

[Two Lane]

Originally posted by boostmaster
This may be a stupid question but when talking about the sweet spot on a turbo in what part of the run is this referring to. 1st - 2nd or third gear at full boost.

Generally refers to the psi-range where maximum efficiency is reached...beyond which no further gains are made.

HTH

 

[boostmaster]

I understand that part. What I am asking is are you refering to peak boost at what part of the run i.e. 27psi in 1st, 25 psi in 2nd and 23psi in3rd. Would the 23psi be considered peak efficiency or would it be 27psi.

 

[JaBoT]

The peak efficiency of a turbo has nothing to do with the gear you are in. It's just the point at where the turbo will not make any more power, usually do to the air charge becoming to hot. If your turbos peak is 25lbs, then its peak is 25lbs in first, second, third or forth.

As far as having different boost in first second and third gears, that is either programmed in you chip or you are having a problem somewhere else.

 

[boostmaster]

I understand that part of the explanation, but I guess what I am getting from all this is, I have a TA49 and if the peak effeciency of this turbo is between 23-25psi then I want to be within those spec's when I'm going thru the traps right? But due to certain factors such as chip programing, boost creep or whatever, does that mean that I may start out at 27psi in first gear? That's what I'm trying to understand.