joefarmer

Now that I have your attention...

I've been trying to find the A/R ratio for the stock 12cm2 housing and how that corresponds to how well it flows with the 14 and 16 housings. I've found a few guesses, but I have no idea if they're even close:

"Industry standard T3 flange for the exhaust inlet. They use similar t04s style housing on compressor 4". The compressor size is on par with a T04S. 4" inlets are standard. The wheels design is comparable to the Garret GT class, if not a tad better. The compressor does flow about 60~61 lb/min, which is good for the 600~650hp [gasser] range. The A/R on the exhaust housing is supposedly .55a/r. The housing is a divided tang setup which decreases the A/R of the turbo. This speeds the spool and decreases lag, but it gives less flow."

Another source had this to say:

"From what I've read the 9 and 12 translate (very loosely) to about a .45 and .65 A/R respectively, so I'll go out on a limb and extrapolate to ~.80, 1.0, and 1.25 for the 14, 16, and 18. This seems somewhat intuitive, as the larger area would be one part of the Area/Radius, and the radius must be fairly constant, as the housings are interchangeable."

I'm not sure what to believe. Anyone KNOW the A/R ratio of the HX35 turbo?

brandon.

got...DIESEL?

it's too small for real power by itself Seriously Brandon I have been sharpening that pencil for a long time now. I actually had one tech at holset going to e-mail the maps and specs to me because he had put in his two weeks and was to go work for schwitzer. It never happened though....go figure.

Short of measuring the distance from the center of the inlet's cross section to the center of the turbine wheel, then deviding into the full cross section measurement, I know of no other real concrete method of finding the actual A/R. When I take mine off for some strange reason in the near future , I'll measure it up. In the meantime, keep us posted if you find anything out, especially if you get your hands on one of them there compressor maps!

Rods

yr close , i have a T series garrett with a 81 a/r from what iv been told thats somewere around 15 c//m , id say that 12 is pretty close to a 61 a/r witch is common among garretts but @60 lbs/m i wouldnt mess with the hastle , my garrett pushes over 80 lbs with a 70 mm inducer wheel (minor) i havent been on a dyno yet still getting my fuel setup to spool it but id figured 400+ rwhp butt ill just have to c

joefarmer

Sweet. It's not that I'm actually going to run one of these ticking time bombs. I'm basically looking for sizing information to compare a known combination with what I want to run now. Getting this data from Holset is like trying to sneak a peanut past a herd of elephants.

brandon.