What does all this mean?? I feel so stupid but I gotta learn sometime Would this turbo be a good upgrade or not??
SHAFT & WHEEL TRIM 64.5mm

COMPRESSOR WHEEL SUPER 70 60.5mm

( similar to Garrett T61 for comparison purposes )

TURBINE HOUSING A/R .84

COMPRESSOR HOUSING A/R RATIO .70

 

Shaft and Wheel Trim is the size of the exhaust wheel.

Compressor Wheel size in mm.

Turbing Housing A/R .84 is garret, switzers and some others way of measuring the size of the exhaust housing and the direction of the exhaust flow into the wheel. Basically The ratio of the size and shape of the exhaust housing. Similar ratio for the compresor housing. It is hard to explain without some kind of picture. Holsets for example measure exhaust housings by 14cm3 or 16cm3 and so on. They are similar but not exactly the same. Places like High Tech Turbo that build the Switzer (S-300, B1, HTB2) style turbo go ahead and call the exhaust housings for there turbo 12CM or 14CM. But the exhaust housings are acutally measured in the A/R method. They call them 12 or 14 CM to give people any easier understanding to how they will spool. When have you ever heard of someone making 500+ with a 12CM exhaust housing which is what they advertise thier turbos to make. Its simply not accurate. For the life of me i cannot remember off the top of my head what the A/R numbers for what people call the 12CM or "QuickSpool" for the S-300 style turbo and the number for the 14CM. I'll find out and edit it into this post.

As for wether that is a good turbo it depends on what you are doing. In comparison to your hybrid in your signiture its going to flow more air, and spool a bit faster than your 16CM exhaust housing. But you will have a higher drive pressure ratio.

 

not a good turbo for our trucks... those little garretts don't run the pressure ratios we need.

Forrest