Jeff Zwart Pikes Peak International Hill Climb 2014 

Thank you! It would be a crime to cover the sounds the GT3 Cup Turbo makes with music!

Thanks dudes!

Thanks Brandon. Glad you enjoyed it!

It's already up, search the /drive channel for Jeff Zwart Driver's Eye.

4k acquisition on the RED Epic, Canon 1D C, and Panasonic GH4 - then edited in Adobe Premiere and exported as a Pro Res 4k quicktime. RU-vid is pretty nice for their higher resolution capabilities!

Thank you! It's the first time I've seen this, it's really amazing :D

Yep - sequential shifters work that way. Pushing towards you pushes the gear into a lower gear to go slower, and pulling towards you goes to a higher gear to go faster. Think about which way you are pushed into the seat when accelerating or decelerating, and the gear should move in the same way.

My computer couldnt handle it

Rian Fitzy It's super tough on computers, need a good connection, fast machine and big display! Imagine mine rendering it out!

Its the blow off of the turbos... Too much power.

Raul Hernandez Oh I thought that was more of a whistling sound haha. Must be a hell of a powerful turbo then... :O

The Dudester Yes and no. It is in fact the blow of valves, but it's only because he is modulating throttle so the valves are opening and closing little by little barely bleeding, making that funny noise as opposed to a fully closed throttle that makes them open wide with a big WOOSH. I can mimick the same noise with my car by coming on and off the accelerator fast like that.

It is not a BOV since the car has none. It is air circulating backwards into the compressor wheel, this effect is called compressor surge.

Compressor surge. Soon there will arrive bunch of people trying to tell you that it's wastegate chatter or blow-off valve, but they are wrong.

From the turbo winding down as hes coming off the power yeah?

J Stewart Well kinda, if you wanna simplify it extremely. You can have a google on compressor surge if you want to have the full explanation.

I will do that thanks for the clarification.

PePe You know yout wrong right???? It actually is the blow off valve because if you watch the whole length video of the race not only does it tell you bit you can clearly see one of the fuel pumps was failing and causing a loss in power which means the blow off is activating because power is getting cut. I work in a mechanic shop that specializes in turbos so I think I may a thing or two.

+MarkG It was the personal preference of the driver to use this vehicle. The 911 turbo is heavier because of AWD powertrain. GT2 is also a heavier chassis. Its basically a GT2 motor in a lighter GT3. Best of both worlds

Because everything with a turbo is awesome, would you just listen to that Turbo whistle

+MarkG He did, all of those. Watch the times at the end to see what's been tried. The GT3 is a SERIOUS car, the GT2 is a street car to the bone. It makes sense to turbo the GT3 and start off right.

Michelin slicks like he is using perform best around 30psi hot. A 24psi setting when cold will give that pressure after they have warmed up.

Thanks for the reply. That seems like a huge difference from the road cars. Porsche recommends 36/44 for all turbos or turbo-looks, if I'm not mistaken!

montanabb67 Yes, it is quite different from the road cars. The GT3 Cup weighs about 500 lbs. less than the street Turbo, even with a full cage, and the Porsche Cup race slicks are a different construction and compound than the road tires. In their race tire catalog, Michelin actually recommends a starting cold pressure of 22psi to reach the optimum range of 30-32psi hot. See www.scribd.com/doc/25197303/Michelin-Race-Tire-Catalog

Thanks for the information. It's interesting to see how the compound makes a massive difference to the inflation pressures. Do race tires use nitrogen or normal air? 8-10 psi jump seems like quite a lot! But then again, I guess the transfer of heat would be much greater with race tires compared to road tires. On a side note, many people I have talked with seem to believe the 36/44 cold pressures are too stiff for street/spirited street driving. We 'try' to maintain that on our cars as much as possible. We should never argue with the tire manufacturers!

It is not just the compound that effects pressures, but the tire construction (sidewall stiffness, etc), weight of the car and how hard (and long) it is driven in a stint (the PP hillclimb only lasts 10 minutes), plus the surface conditions of the road/track (abrasiveness and temps). Race teams often use nitrogen, but it is not that effective unless the tire is purged and refilled several times, something casual racers are not likely to do. "Normal air" is 78% nitrogen already, along with 21% oxygen, and if it is dry, it is not a problem. It is the traces of water vapor that cause inordinate pressure increases with rising tire temps. An 8-10psi increase is not unusual for a tire driven that hard on a hot asphalt surface. I routinely see that kind of increase in DOT-legal street tires in a 20-minute track session, or even a 4-6 psi increase after 4 autocross laps of one minute each with a 5-minute "rest" in between laps. From what I have read, Jeff's team used active tire warmers to bring the tires up to temp (and pressure) before starting his runs up the mountain. The 24psi reference seen at the beginning of this clip was a cold pressure taken when the tires were mounted, I believe. They did some careful testing with the Michelin Cup slicks to determine ideal setup before the event, so I wouldn't second-guess their choices. The tires performed very well, from all reports, and the car's handling was excellent, according to JZ. It was the fuel pump problem that let them down. The 36/44 psi recommendation you mention is Porsche's "door-sill plate" recommendation for cold pressure on OEM tires, no? I believe that is for "fully loaded" conditions (driver and passenger plus luggage) in normal street driving. For "partial load" (driver only) the cold pressure recommendation is 33/39psi on the Turbo, I think. If the car is used hard, on the track, lower starting pressures would be appropriate, as pressure gains would be greater.

2011 I believe.

with this type of comment, I'm sure you never did anyway :)) .. and you never will !