Area Under the Curve
#16
I dont know for sure because I never dynoed her. Somewhere around 600 depending on which dyno would be a rough estimate.
#17
It's amazing you can get mid-5s for 60-130 with "only" 600whp pump. Presumably your 5.5 was on racegas? Any idea what your best time is on pump gas?
#18
Yes, the 5.5 was on race gas. The car runs easily repeatable sub 6s on race. I have never tried with the current setup on pump. I would estimate it would be around 6.3-6.4s.
#21
this is a great graphical demonstration on how the theory of the VTG's have not proven to be a game changer in the practical application - conventional turbos with new vane geometries working within their efficiency islands are still superior
#22
Yeah, I was thinking about this too. Seems like the vtgs could be tweaked some more or perhaps better vane modulation would produce improvements? Or is this just a limitation in the inherent design?
#23
Now take the car in 6th gear, start at 1000 rpms and jam the pedal - the torque will hit at 2100 rpms. This is not seen in the other gears so Porsche did not lie, but the skyscraper of torque is not there for 90% of driving situations. The only ones getting their money's worth on the VTG's are the autobahn heroes dragging from 200-300 kph...
#24
It's deceiving since the stock vtg's are definitely slow to respond, so much so, that I was disappointed so I upgraded to 63.5 mm vtgs a while back. For stock, it seemed more like a boost threshold issue but it's been a while. The upgraded vtgs performed significantly better, seemingly eliminated the stock problem. I thought these were great until I saw Mike's A28 data and man, those just take off. I remember comparing several gears and times with Mike's A28 to see if my vtgs would have an edge somewhere. Couldn't find one.
#25
The stock car has been programmed to not allow full torque at lower rpms (I don't know the threshold). Todd at Proto told me this and the ecu tune upgrade from Proto does allow full torque at lower rpms and there is a significant boost in mid-range response with reduced lag. I'm currently getting the pbox data to compare stock car vs tuned car and then I'll add the data for upgraded vtg. So far the results show a big improvement with just the tune over the stock values.
#27
Very impressive all around. Have you been in a vtg car? What is your subjective impression of boost response/lag with vtgs vs your a28? Just curious. On paper your a28s seem to have it all.
#28
I have been in a VTG car but I did not get to drive so I cant really comment. I have been extremely happy with the A28s though.