How much airflow is a .80A/R T25 "SR20" turbo good for? Also what are the siZes of the compressor and turbine wheels? (I know I made a capital "Z" but my "Z" button only works when the shift key is held down... Weird I know..) I have read through the turbo tech pages on the garrett website several times, but its still kinda foggy.. Now, I understand that A/R mean area ratio, and this is referring to the compressor housing correct? Based on that number is it possible to figure out the wheel siZes on my own? Also, Is 16psi reasonable from this turbo, being near the efficiency range I mean... Sorry for the newb questions I'm still getting my feet wet to how all this works..

 

find the compressor and turbine maps. good luck.

 

After a half hour of searching I found an old site on google that lists this turbos specs:
.80 A/R compressor housing
60 "trim" compressor wheel
.64 A/R turbine
62 trim turbine
Airflow was said to be 28 lbs/min, does that sound correct? Also is there a way of calculating horsepower based on this airflow number?

 

Isn't the SR20 turbo (idk if there is a difference b/n blacktop and redtop ones) the 2560? I thought Garret's website said something like that.

 

^No, the regular T25 is a small journal bearing.
On a 1.6 with good management and 3" exhaust, it's good for about 220whp at 16psi, fully spooled by 3k, and that's it. You can squeeze another 10whp or so out of a 1.8. Torque will never be above about 190wtq and it starts to fall of about 5000 rpm.

The T28 is BB, and came on GTiR motors of various models and years and is comparable to a 2560.

 

ask and you shall recieve.

 

lb/min / AFR / (BSFC/60)


28 / 11.5:1 / .00916 = 265BHP

 

this is the difference between the T25 and a T28, the compressor wheel:



the 2560 uses a 60mm compressor wheel.

t28 = t25 + T3

 

Wow thanks so much for all the info! When looking at that first map, is it read like a contour map? Like does each line represent a given "Altitude" or pressure? Thanks again all this info is great!