A/R sizes or conversions

D

Diesel Dummy

D-Maxin
Joined
Dec 29, 2006
Messages
542
Does anybody know where i can find a list of A/R sizes converted to cm, just trying to learn alittle more about exhaust housings and the sizes in A/R terms.

DD
 
i made a thread while back and no-one seamed to knwo the anserw
 
Holset used cm. Everyone else used A/R. Since Holset kept their measuring process fairly proprietary, the conversion process is undefined. There have been guesses and the other threads refer to these guesses.
 
joefarmer said:
Holset used cm. Everyone else used A/R. Since Holset kept their measuring process fairly proprietary, the conversion process is undefined. There have been guesses and the other threads refer to these guesses.
Click to expand...


Brandon summed it up, there are some guess, but they are just guesses.


Since A/R is a ratio, and holset uses a cm^2. I don't think there it is a linear multiplier.
 
I've been thinking the same, but for example II and High tech say their S300 based chargers are 12 or 14 cm for cast, but label them as .80 = 14cm is that correct in that 1 case? Is a .80 t-3 smaller than a .80 t-4, what are they measuring to get the ratio?
 
The area that they are measuring is the cross section of the smallest point of the housing before the exhaust goes into the turbine. The A/R is the area divided by radius in cm. So if a 14cm² housing is a .80ar, the radius is 17.5cm. If you have a 14cm² housing on a bigger turbo with a radius of like 22cm, then the AR would be .64.
compressor_housing_showing_A-R_characteristic.gif
 
You must log in or register to reply here.
Top