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Interesting book! Were does one get one of those?!?
Books are sold by Porsche during the release of new models. Usually you have to buy them close to the release of the new vehicle, but PDF versions do end up floating around.
Originally Posted by rs10
Very interesting post as well - thanks!
Do you know if the 987 (or the 997)'s vents into the wheel well are shaped and positioned like the 996 turbo's (as shown earlier in this thread)? Or like the 996 GT3s? Or ... ?
Thanks again!
You're welcome! They’re more like the C4S and Turbo’s than the GT3’s. GT3 makes use of additional brake cooling deflectors, which necessitate the open airflow through the wheel housing liner.
Originally Posted by vandersmith
Do other 996s not have wheel liner fins like this?
This photo shows a C4S and Turbo style fender liner I believe…
If you notice all cars that have relief for pressure in the wheel well is at the top of the fender - if you open that area up
No personal opinion or experience on this myself but this informed video just popped up in my youtube feed and it's super interesting given the topic of this thread.
You're welcome! They’re more like the C4S and Turbo’s than the GT3’s. GT3 makes use of additional brake cooling deflectors, which necessitate the open airflow through the wheel housing liner.
Again very interesting. I don't suppose you know if the relevant part of the fender liner from a C4S, 987 or 997 could be used on a 996 C2?
Been following this thread, and there are some interesting things here. One of the things I see being overlooked to some extent. There's two sides to the drag ratio, one is the leading side of the equation where air is pushed through or around structures. The other side of the equation is the air extraction or the 'vacuum' side. Air recombines after leaving an area of disturbance. This side is often given short shrift.
Again from an aerodynamic theme, the original P-51 Mustang aircraft was water cooled. This allowed it to have a very high volumetric efficiency. One of the byproducts was the ducting for the radiator(seen on the belly of the fuselage, a snorkel facing forward). The original design was done poorly, and caused a pressure bubble to be formed in the inlet. Once it was reworked, and the adiabatic effects of heating the air were taken into account, the venting of the hot exhaust from there actually improved the speed of the plane!
Back to cars, I once owned a car called a Cord 812. Along with the Chrysler Airflow, it was one of the first cars to make serious use of aerodynamics. It had contoured fenders with hideaway headlights. Back sloped windscreen. No running boards(first car without). Flat under-floor, and even the door handles were teardrop shaped. So, it's nothing new, but it is a tough thing to solve. Without a wind tunnel it's so hard to prove out, even something that looks like a solution, may not be.
So, don't get too wrapped up in just the venting of the intake air. Also consider more the effects as the air is warmed(or not) and how and where it recombines after going around the obstruction.
Again very interesting. I don't suppose you know if the relevant part of the fender liner from a C4S, 987 or 997 could be used on a 996 C2?
Thanks again!
Originally Posted by b3freak
Could I please get a parts list, I upgraded my bumper and feel some underbelly parts are missing. Thanks!
Looking at it now, there might be subtle differences in the way that the forward edge meets the bumper if the car does not have the C4S /Turbo/ 40th Anniversary style bumper. There will probably be a few different variations of this “conversion” whether you want to go with the full conversion including the bumper all ducting around the radiators, and the fender liners. Just FYI, the non vented fender liner is a one piece liner while the later vented style uses two pieces to accomplish the same thing.
See below:
Vented style:
I don’t really know if one could simply adapt “just “ the vented fender liner, to really get the most out of the mod you would want to go all out. I’ll look at what is involved and let you know if it’s worth the time. I'll report back soon!
Yes it can, in conjunction with the other pieces. The 40th Anniversary cars were essentially C2’s, which had this setup.
If you want I can put together a parts list with our Pelican part numbers. Let me know.
I'm also interested. Definitely if it can be made to work without changing everything from the bumper to the wheel well. Maybe if can't.
So there's interest for Carreras who have a turbo front bumper, and for Carreras that don't (yet) have a turbo front bumper.
By the way, it sounds like the discussion is now focused on C4S/Turbo wheel well liners. I don't suppose the 987 or 997 parts would work?
Finally, I understand the Turbo and C4S still have the same opening on the bottom of the car as the Carrera. (Or is it a similar opening with a different shape?) What about the 987 and 997?
Not exactly rocket since. You could just cut some vents with an exacto/stanley knife.
You could. But they wouldn't direct air outwards like the C4S/Turbo vents do. So rather than making things better, they might welk make things worse.
Originally Posted by beetleything
BUT as poster above said - unless you are going really fast i.e. a race track - i don't think it's going to make a difference.
But if you are going fast, like on a race track, then it probably is going to make a difference.
At 124 mph (200 kmph), the TT has 6kg of lift in the front, versus 24kg for the Carrera, around 12kg for the C4S (due to a smaller lip spoiler than the TT - and whereas I'm sure of the other two, the C4S is from memory), and 13 for the GT3. Small differences, it seems. But C4Ss and Carreras with the aerokit (identical to the GT3) are said to be recognizably more tied down in the front at speed - which is consistently reported as a very good thing.
Of course, it's not all because of the vent change. But I'm pretty sure it helps. Indeed, the spoiler part of the bumper on the GT3 extends even further down than the TT's, so all else being equal, one would expect the GT3 to have less lift than the TT, not more.
There is always the question, will venting air from the wheel wells in the same way as a TT/C4S/40AE, or a 987 or 997 work if you don't have the same front bumper and bits in between.
You probabbly don't have to have the exact same bumper, but I had a look at pictures of a 987.1 bumper from a non S Boxter, and it seems to me it is very similar to a 996 bumper. You wouldn't mistake them, of course. But it seems to me that air hitting the car at any given height and any given distance from center will be directed in roughly the same direction, and the left and right openings have roughly the same size and position. So if the bits between the bumper and the wheel well vents are similar, then 987 (and probably 997) style vents would work.
I also had a quick look at wheel well vents in s 997, and they look rather like the C4S vents. They also direct the air horizontally outwards. Though the vents together fill a rectangular space, instead of a triangular one. They are fruther inboard than I expected, though this may also be the case with a C4S.
01-25-2017, 01:26 PM
