rotary downshift

can anyonehere help me .. im to be purchasing a turbo and manifold both s4 now the twin scroll has been removed and pluged off and the runners on the turbo have been ported to match can somone describe to me what this means .. and the benafits of doing this/... would be greeatly appreciated

pistonsuk

The twin scroll is basicly a flap the covers one of the scrolls (openings that funnel exh. gases to the turbine wheel) under low load conditions. This doubles the velocity of the remaining gas through the other scroll. The equation that governs the force excerted on the turbine wheel has the area to the first power and velocity to the second. Therefore by halving the area (shutting off on scroll) and doubling the velocity int he other scroll (twice the volume through one scroll) the overall torque output of the turbine in increased. In short, the system makes the turbo respond as a smaller A/R turbo would under low flow (fast spool) and as a larger A/R turbo under high flow (low restriction).

Benefits to removing it?: a slight reduction in weight, slightly less exhaust gas restriction, complexity?

Justin

need-a-t2

iTrader: (9)

you'll aslo get better top end flow with the twin scroll removed. this is why most people remove it.

fastrotaries

I never like it, and with my DP never noticed any difference in the low end. Top end was ALOT better though.

RETed

http://www.fc3spro.com/TECH/HOWTO/TU...ORT/tport.html


-Ted