t-15 efficiency

Jtrain

New member
The Explorer sports are using the T-15's right?

Can anyone translate those turbo graphs to tell me about what PSI these turbo's stop being efficient?

EG: my G18's really don't add much power after 18/19 psi.
 
15 psi is the most efficient but if that was the case, no one would need a 3 bar. Theres a couple more PSI in it (1-2 PSI) Maybe not efficient, but its there
 
Understood. I can definitely see the need and use for a 3 bar sensor. My G ride with my current motor set up rolls about 600 wheel at 17.X Psi... 18PSI is about 615 whp and 620 torque. 20psi is ~625 wheel. 16 PSI was about 560/570.

You hit that mark and the car feels like it's working so much harder and getting nothing done- Just wanted to know where that was with these baby turbos.
 
I thought that we used the Garret GT15. If so here is the map profile.

1bar is 14.7lbs (normal air pressure at sea level) 2bar is 14.7lbs of boost.

454082-2comp.jpg


As you can see we are pretty close to max efficiency of the turbo.

 
As you look at the graph notice the percentages of the 'islands'? The smallest one in the middle shows a efficiency rating of 75%. That is the most efficient this turbo is.

So if you boost it to 2.5 bar (22lbs) then the EF rating drops to 72% but the turbo, which normally spins at 150-170000rpm, is now spinning at 210000rpm. That's gonna shorten its life. Plus at that speed more heat will be created as it compresses the air (hence less efficient) which will affect other things like what timing you can run.

There is a lot more to it than just that though. ;)
 
The gt15's in the sho are not off the shelf turbos but the turbine and compressor are closer to a GT1548 not the GT1544.


The gt1544 are past the map at the air flow requirements of a stock SHO (about 18 lb/min at 365 hp).
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