I now have 'before' and 'after' dyno results from Torque Performance.
Stock S2 (2 years ago) figures close to factory:
139kW at wheels
if assume 30kW lost to drive train=169kW at flywheel or about 230HP
Today (fuel and turbo remap, Miltek cat-back, Samco inlet hoses):
174kW at wheels
if drive train loss is the same that's about 204kW or close to 280HP
Torque looked like it was up around RS2 figures (400+ NM), but I don't know how accurate that is on this sort of dyno.
Roughly a 25% imporvement after a fairly inexpensive upgrade seems pretty good to me.
Notes if other S2 owners are interested:
-Boost is up from 15psi to just over 20psi. Air/fuel hovered around 12.5.
-One interesting thing with two runs: guys reckoned there was some knocking at about 3k, (this was really bad some time ago, before new fuel pump and filter). On the second run the ECU appeard to retard timing and drop boost (only hit 18psi), BUT result was better torque and HIGHER total power. One guess is that this might suggest the timing is a bit too advanced and would benifit from being pulled back a bit.
-Air/fuel got quite rich over about 5500rpm which may limit power. Probably not a bad thing though to protect from heat/knock.
-Torque curve is nice and steep: max torque down at about 3000rpm now? ;D
and i got to watch it all..
Quote from: urq20v on March 05, 2005, 03:26:44 PM
Didnt you do a run Noel?
yes, but in the levin. 98kw at the wheels.
I did the RS4 last year and got 229kw at the wheels, which i thought was a bit high.
Here's the plot, split into two parts (sorry about the quality: scanner broken).
Red is first run, blue is second (less boost, but more power).
Grey pencil lines are roughly the stock results from two years ago.
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I don't know how accurate A/F is (measured at exhaust tip, so after cats), but it is interesting to see how the ratio goes flat at about 11.5:1. Torque guys reckoned may see more power at high revs if leaned out some more, but I think I'd rather it stayed rich to prevent a melt-down.
Big black puff from exhaust on rev-limit, which I guess means a lot of extra fuel when backing off.