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Are there any significant advantages to lowering the car for track use?

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Old 01-17-2011, 01:44 PM
  #16  
FFaust
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Originally Posted by mobonic
...the lower the car the lower the center of gravity, which will result in better handling and better weight transfer...
Absolutely!

In a turn, your C of G wants to keep going straight, and resist the change of direction (something to do with one of Newton's laws that says that "a body in motion..." I think) . The "only" thing to oppose this and cause the turn is the tire contact patch on the outside wheels (oversimplified, I know).

Therefore, it's fairly easy to picture the relationship between the C of G and the tire contact patch, and to "see" how the two forces oppose each other. Therefore, the more "in line" and in direct opposition the two forces are, which is enhanced by a lowered car and lowered C of G, the more balanced everything becomes. And as we all know, driving fast and in control is all about balance (hope I said that right).

Of course, this is all on paper. In real life, where road surface, intended use, mechanical limitations... and budget allowance are thrown in, YMMV.

It's all very fascinating
Old 01-17-2011, 01:44 PM
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fc-racer
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I'd recommend lowering ~10mm. This doesn't affect the suspension angles enough to be a net negative and you get the benefits of lower centre of gravity, less weight transfer and potentially better aero. Perhaps the biggest benefit is aesthetic; it just looks a lot nicer. The pics in my sig are with the car lowered 10mm for a visual reference.

If you do decide to lower, here is the factory way of measuring and the factory heights:

WM 4400TW Adjustment values for suspension alignment Technical values

Location Description Type Basic value Tolerance 1 Tolerance 2
Front axle height Adjustment value 108 mm + 5 mm - 0 mm

Rear axle height Adjustment value 133 mm + 5 mm - 0 mm

Vehicle height

Note

The following values relate to the empty weight, i.e. full fuel tank/fluid reservoirs, vehicle with tools, but without driver or additional weights!

Vehicle height 911 GT3/911 GT3 RS (997) RoW/USA

Front axle

Height with 19-inch wheels
→ Adjustment value: 108 mm+ 5 mm- 0 mm → :

From road contact surface to lower edge of hexagon-head bolt of cross-member threaded connection to the body.

Rear axle

Height with 19-inch wheels
→ Adjustment value: 133 mm+ 5 mm- 0 mm → :

From wheel contact surface to the locating bore in the rear-axle side section (between toe and camber eccentrics).

Permitted transverse inclination of the vehicle: Max. difference in height, left to right = 5 mm.

Max. wheel-load difference from right to left on front and rear axle is 15 kg.

Old 01-17-2011, 03:44 PM
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DavidNR
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Interesting difference in rake between the .1 & .2. What do you think is the reason? Downforce & turn in grip?
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Old 01-17-2011, 09:49 PM
  #19  
deputydog95
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Originally Posted by TRAKCAR
I'm lowered 10mm from factory ride height, maintaining the factory rake.
I would not lowered it too much for Sebring. IMHO most cars are too low and start bouncing more..
You couldn't see us but you had a cheering section as we were watching that Scuderia try to catch you lap after lap. It was fun seeing you stick it to that Ferrari

You were mooooovin' out there in the last session.
Old 01-17-2011, 09:57 PM
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Originally Posted by Izzone
And you said all stock......so now I know how you get those lap times......super glue on your tires and a lowered car
Judging by his times I have to believe its even more sinister. Maybe electro magnets under the track. I'm still not sure how the hell he's doing it...
Old 01-17-2011, 10:24 PM
  #21  
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You couldn't see us but you had a cheering section as we were watching that Scuderia try to catch you lap after lap. It was fun seeing you stick it to that Ferrari

DeputyDog, sorry I was a little foggy that morning. Brain no workie with hangover until caffeine hits..

LOL, thanks for cheering, but I wasn't sticking anything, Rad could have passed me pretty much on half the track at will. I left him on very few corners if any.
I was driving my *** off and he just was entertained and wanted it on film ;-)
He also wanted to see my line since it was his first! day at Sebring. Very good driver, very fast car..

I have seen a few '10RS do 2:19's on Hoosiers in warmer weather. Erik, Juan, all the decent DE weekend warriors will run my times in my car. It's just that much faster then the MK1 GT3 and RS..
Old 01-17-2011, 10:48 PM
  #22  
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First day at Sebring and he drives like that??? Does he have a pro background or something? Impressive. If you were consistently turning 220's, and with him essentially right on your tail, that's amazing for sebring newb. When I break 224 in my car, I'm treating myself to a .2 RS the next day. I can say that with confidence as I know it's a long way off
Old 01-17-2011, 11:02 PM
  #23  
aussie jimmy
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i was impressed too. i have seen quite a few scuds and strads vs gt3 before, but the power difference on that car was amazing. and he took unorthodox lines and just muscled through, he didn't wait for other drivers to acknowledge that he was there.
he is on here, so maybe he can explain....????hahaha
Old 01-18-2011, 09:09 AM
  #24  
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NJ-GT is here often, but I know he's travelling a lot. he could not stay on Sunday. Too bad..
Old 01-18-2011, 02:46 PM
  #25  
deputydog95
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Originally Posted by aussie jimmy
i was impressed too. i have seen quite a few scuds and strads vs gt3 before, but the power difference on that car was amazing. and he took unorthodox lines and just muscled through, he didn't wait for other drivers to acknowledge that he was there.
he is on here, so maybe he can explain....????hahaha

Were you at winterfest too?

When you say the power difference was amazing, did you mean the Scud was faster? Either he was holding back or he couldn't get past Peter on the front straight. We couldn't see anywhere else on the track from where we were watching.
Old 01-18-2011, 02:52 PM
  #26  
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He was holding back on the straights and probably faster in most corners..
Old 01-18-2011, 06:38 PM
  #27  
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Originally Posted by deputydog95
Were you at winterfest too?

When you say the power difference was amazing, did you mean the Scud was faster? Either he was holding back or he couldn't get past Peter on the front straight. We couldn't see anywhere else on the track from where we were watching.
i was there through the power of the internet! (and peter's good recordings)

check peter's video on the other thread. nj-gt was holding back, it is fun to follow and playfully torment sometimes. i think he was watching and learning the lines, as it was forementioned that it was his first time at sebring. when he passed, the scud was much faster. faster than a 50bhp advantage usually represents. you could see him pull away everywhere, even when he took any odd line into corners......there was one on the entry to back straight where he went very wide to the left and hooked it in like a go kart. the thing was finding grip everywhere. maybe he was on slicks? he was just rocketing out of the corners. obviously, peter probably knows most of the guys on track and out of respect and safety, he waited to pass them, but mr.scud just muscled on through like no tomorrow. a scud and rs should be doing very similar laptimes, but the difference here could easily have been 2-3 seconds.
Old 01-18-2011, 07:35 PM
  #28  
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Deputydog, just click on my signature. The film with the Ferrari is the 4th from the bottom.

The Ferrari was on Hoosier A6 (autocross tires) they heat up fast, but then overheat.
Yeah, the Ferrari was in a bit of a hurry, we're not supposed to go 3 wide, but he had plenty of room..
he took a lot of passes, but he did not "Get lucky" he seemed very in control and a few times when other cars did not give an indication the has seen hem coming he backed off and dd not take a pass.

When NJGT showes up, he will post the few laps where he was following (Toying with?) me..
Old 01-18-2011, 11:04 PM
  #29  
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Come on Pete. Tie that V1 cord already

The Ferrari seems to have endless grip no matter what line he drives. That was amazing. Even if he totally botched a corner he didn't lose any speed or track position. Is that more of a function of the driver (who is obviously very good) or at least partially the stability aids in the car. I'm still shocked at how fast that Scud is. Very impressive.
Old 01-18-2011, 11:08 PM
  #30  
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Was that pass coming out of bishop's bend as hairy as it looked? I haven't run an "open passing" event yet. Looks sketchy. I'm used to driving a line. You guys are constantly changing your lines depending on the position of the other cars in the corner. Looks more like racing than DE.



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