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First track day summary

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Old 11-01-2015, 01:53 PM
  #16  
Martini racer
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Originally Posted by 4carl
I'll have to see how things go together for the 20th. Are you going ? I Really wanted to do Mooty's day the timing just didnt work.

BW for me is either a two day deal or a 450-500mile day. Its 170mi each way 2:45. So either i go up the night before and stay at the beautiful Button Willow Super 8. Or leave the house @ 5am and get home @ 7pm, which is a real grind. carl
wednesday, Nov 18th at Calspeed way. Fast toys club, it's a good group and GT4 will shine at ROVAL config.
Old 11-01-2015, 03:11 PM
  #17  
jpgunn
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Carl,

I just ran my GT4 yesterday for the first time at El Toro (AutoX). Camber -1.9/-1.6, toe out 1 total in front and toe in 2 in rear. Car definitely wanted to push in the slow stuff. Was good in the faster stuff, but still had push.

I am going to:
go full stiff rear bar
Lower the car to minimum factory ride heights (10mm lower than they ship)
Put shims in front to get as much camber as I can while keeping factory toe links
Set rear to maximum factory camber while maintaining 2' total toe in. Not sure shims will be needed here.

Wonderful car overall.
Old 11-01-2015, 05:43 PM
  #18  
4carl
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Originally Posted by jpgunn
Carl,

I just ran my GT4 yesterday for the first time at El Toro (AutoX). Camber -1.9/-1.6, toe out 1 total in front and toe in 2 in rear. Car definitely wanted to push in the slow stuff. Was good in the faster stuff, but still had push.

I am going to:
go full stiff rear bar
Lower the car to minimum factory ride heights (10mm lower than they ship)
Put shims in front to get as much camber as I can while keeping factory toe links
Set rear to maximum factory camber while maintaining 2' total toe in. Not sure shims will be needed here.

Wonderful car overall.
Looks like you're running the same set up as me. Were you running both bars in the middle? tire pressures? tx carl
Old 11-01-2015, 06:52 PM
  #19  
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Originally Posted by 4carl
Looks like you're running the same set up as me. Were you running both bars in the middle? tire pressures? tx carl
Both Bars in the middle.

I got Dunlops on my car, and for pressures I was trying 31 front and 32/33 rear. I actually think it probably needed lower in the front (28 maybe), but I did not try.

Changing the front camber turned out to be simple. I measured before, and it was 1.6 degrees with about 1/4" Total toe in. I then loosened the nuts on the strut tower and slid them in as far as possible. Got to 1.9 degrees, and then measured the toe, and it was 1/16" total out, which I thought would be fine. The plus is, it is simple to go back to stock at this point (3 bolts loose per side and slide back to original marks). Obviously once I add shims, etc. it won't be as simple, but the shim is a factory method for adjusting the camber on these cars, so I think it is fine. Just have to watch the Caster does not get out of control with them.

My thought is to add a 6mm shim on both sides in the front. That should put me at 2.5 Degrees. Will measure total tie Rod length from the boot that comes out of Rack and Pinion and then determine how much thread is in the Rod End. I would not want less than 10mm. If I have more than 10mm, I would add more shims to the arm to get more negative camber.

I have not heard anyone determine the limits of the stock Tie Rods yet (without messing around with new Rod Ends or rear aftermarket toe arms). For the front, I have read posts that claim Manthey says the limit is 2.5, and others say that their "Shop" says it is 3 degrees based on their GT3 experience. For the rear, it seems most think it is -1.6, but I can tell you, mine came set at -1.6, and there is definitely more adjustment left (haven't played with it yet, and it looks like it is probably only .2 degrees).
Old 11-01-2015, 07:05 PM
  #20  
4carl
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Originally Posted by jpgunn
Both Bars in the middle.

I got Dunlops on my car, and for pressures I was trying 31 front and 32/33 rear. I actually think it probably needed lower in the front (28 maybe), but I did not try.

Changing the front camber turned out to be simple. I measured before, and it was 1.6 degrees with about 1/4" Total toe in. I then loosened the nuts on the strut tower and slid them in as far as possible. Got to 1.9 degrees, and then measured the toe, and it was 1/16" total out, which I thought would be fine. The plus is, it is simple to go back to stock at this point (3 bolts loose per side and slide back to original marks). Obviously once I add shims, etc. it won't be as simple, but the shim is a factory method for adjusting the camber on these cars, so I think it is fine. Just have to watch the Caster does not get out of control with them.

My thought is to add a 6mm shim on both sides in the front. That should put me at 2.5 Degrees. Will measure total tie Rod length from the boot that comes out of Rack and Pinion and then determine how much thread is in the Rod End. I would not want less than 10mm. If I have more than 10mm, I would add more shims to the arm to get more negative camber.

I have not heard anyone determine the limits of the stock Tie Rods yet (without messing around with new Rod Ends or rear aftermarket toe arms). For the front, I have read posts that claim Manthey says the limit is 2.5, and others say that their "Shop" says it is 3 degrees based on their GT3 experience. For the rear, it seems most think it is -1.6, but I can tell you, mine came set at -1.6, and there is definitely more adjustment left (haven't played with it yet, and it looks like it is probably only .2 degrees).
It's good to find another hands on guy doing his own setups. There's no better way to learn what does what than doing your own setups.

I started doing mine in 87 after a dealer screwed up my 911 . Over the years I've accumulated slip plates , scales, toe gauge, camber gauge. It can get tedious but you can do it as if not more accurate than a machine.

I can measure toe to .001" that's 1/300th of a degree. That's three times what a machine does. I'm not saying it makes a difference. Carl
Old 11-01-2015, 08:10 PM
  #21  
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I have heard the Dunlops require higher pressure than the Michelins. Accordingly, I Was running 32/34 and bumped it up to 34/36 yesterday in the mountains. Above 35 on the fronts, the steering feels off to me. The higher pressure produced a car that handles bumps slightly better, but slightly more numb feeling.

All anecdotal of course. Actual track testing needed.



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