If you take the flow rate and a T4 TS .84 housing, what will the equal T3 housing be flow wise? I surely are bigger and should flow more than a T3 .82!

 

The normal math is 60% of the housing for equivalent single scroll, in this case is 0.50 A/r. The conversion from T4 to T3 is a little trickier since it really depends on volute cross section and volume (nozzle area).

I will have to look and see if I can find the math.

Aaron

 

^^^ What he said.

Just a wild, left field comparision, but I had a 0.58 A/R T4 housing T67/T350 on my old car. Spooled very similar to a friend's car with the GT35/T350 in a 0.82 T3. Considering the larger compressor yet similar lag, I'd put the 0.58 A/R T4 in the range of a 0.7-0.75 T3 housing. Not a real big difference, but the advantage (power wise) going to the 0.82 T3. That 0.58 T4 definitely looked smaller internally then the 0.82 T3 housing.

The GT T3 housings flow pretty well.