Quote:
Originally Posted by Soorena
I don't think anyone here mentioned that the boost will be limited during the whole powerband. It wouldn't be logical not to push more up top than down low, specially in a high comp engine like this. Engines take boost easier up top than they in low or mid range because boost means heat and heat kills engines. Up top, because the engine runs faster, it basically sends out heat faster. In lower RPMs, heat gets trapped in much longer and as a result can do more harm. No one would strap a TVS to an engine and limits boost in higher RPMs.
Even if we say they limit boost, still engine will make more power up top because it's getting more air and air means power not pressure.
This dyno shot i found is APR's stage III 4.2 which has this very same Eaton TVS 1740 and i think it's say to say that we will get a very similar powerband with this TVS blower due to the similarities between 4.2 FSIs and S65s.
Look how beautifully it mimics the OEM torque curve. Torque rises, peaks at midrange and then drops. Just like how our engines act. But with centrifugal, it just pushes up the torque all the way through the redline. Certainly our engines in NA form don't make more torque up top than they do in mid range, so saying centrifugal keeps the OEM character is not right.
Now only if Harrop guys would give us a compressor map of this TVS 1740 we could see how this TVS would do with S65 and how does against Vortech and Rotrex units.
BTW, Why the thread title still is "Harrop Twin Screw"? TVS and TS are very different types of PD's. One is a air mover, the other is a air pusher. |
Too bad we can't get APR to tune the Harrop SC for the S65... Where is Arin from APR to comment? (people that came from the whole VW/ Scene know what I mean... lol)
APR is a very big and well respected company taking Harrops Hardware and combining their software and R & D to get the kit to work in the Audi RS4... Wonder what equivalent software company is doing it for the S65?