Quote:
Originally Posted by SeanWRT
Endeav,
first thing to clarify - the dyno plot posted in my earlier post was not my car, so I'm not comfortable with your expression. "SeanWRT makes XXX at XXX."
Second, they were all 4th gear pulls, I'm assuming yours are 5th gear. Makes about 500rpm difference.
Next, 400lbft@3500rpm doesn't mean you're going to get it in the real world. It happens only when boost is fully built from earlier rpm and WOT. In real world however, low rpm downshift to higher rpm (even if it's 5k+), you don't have instant power. Still needs a few hundred (thousand) rpm to spool.
One more example - BMW says M2 peak torque starts from 1400rpm (maybe 1700 can't remember for sure). What does it mean? It does NOT mean every time you WOT and needle past 1400, you get peak torque. Instead, it means if you hold the rpm at 1400 for as long as it take, peak torque you will eventually get.
Next, PS2 lags by about 800-1000rpm on 3rd gear, compared to stock, a hard fact. Granted, at same boost, PS2 makes more power. Keep in mind though, how lag is felt is the time between power off/little and on.
Imagine you cruise at below 2000, you're pretty much are off boost completely because ps2 big turbine very likely isn't responding to exhaust gas at all on partial throttle. Smaller turbine from stock turbo already working though not enough to make boost. A crucial difference on how lag is perceived in real world.
When applying pedal, ps2 is less ready in the first place, on top of being slower in building boost.
Lastly. In the end, it comes down to how and where the car is driven. F1 car makes 700hp from turbocharged 1.6L. Laggy AF on street everyone should realize, but no one talks about lag on track. Even on street, Manhattan stop and go and Midwest 50mph so called bumper to bumper are different.
Ok office I just arrived. Let's agree to disagree.
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Didn't mean to come off stand-offish at all by using your user ID when discussing the dyno plots. I just assumed that was your dyno graph and used it as a point of reference. My fault for assuming - sorry!
As someone who has driven a PS2 car for over a year and clocked many kilometers on this setup I have to say dyno plots and datalogs don't know really show how responsive this turbo truly is. Real world performance is completely different than a set of numbers on a graph or spreadsheet. I agree, at 2000 RPM if I tried to floor it I would be lagging behind and be unable to experience the true power this turbo offers - 100% agree.
What I disagree with is that you're saying at > 5000 RPM the turbo is still laggy. I have to say, any time I'm above 3500 RPM and floor it, the turbo builds boost insanely quick and absolutely destroys the tires... there's no shortage of torque.
Agree to disagree
