GT4RS - Track Setup
#1186
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My setup with front shims, front Porsche Motorsport camber plates and longer rear toe arms.
Front. -3.23. Toe 1mm out each side
Rear. -2.55. Toe 2.2 mm in each side.
Front left tyre shoulder still delaminated with these settings
Front. -3.23. Toe 1mm out each side
Rear. -2.55. Toe 2.2 mm in each side.
Front left tyre shoulder still delaminated with these settings
#1187
Three Wheelin'
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If you want your camber in the -2s you pretty much need rear toe links to have freedom with your toe. They aren't that much and I have an extra set to sell. PM me if interested.
I don't know where that alignment really came from but it won't work very well. The car will push, and with your driving skill, you won't be happy. See Misha's video of his first GT4 RS ride. They did an alignment at Manthey and show you the numbers -2.2 and -1.8. With stock tires this is likely to still be on the push side of neutral so I would go the full -.5 difference to the front axle. The Ring is different from pretty much any other 2-4 mile circuit that we will ever encounter. So my recommendation in your case would be to start out with:
Camber: -2.3/-1.8
Toe: 0 front and +12 min each side rear
Caster: no more than 9 degrees ( they need to adjust the LCA bushing after adding the front shim, we've seen that not happen before! )
Ride height:standard OEM to start @ 109/130 (When they add shim, it will lower the car a bit. It may be more off than you might think form the factory too. Each coilover turn is worth about 2mm in ride height)
See Misha's video for their camber recommendations which follow the same parameters that everyone I know uses (-.5 difference to start with). My toe numbers are within the above parameters. +2' then -2' equals 0 front. +10' then +2' equals +12' rear, you want stability in the rear. Drive the car, see what you think, and adjust from there. Three hundred dollar alignments are peanuts in the scheme of things for tracking your car.
Misha's video (at 3:50)
I don't know where that alignment really came from but it won't work very well. The car will push, and with your driving skill, you won't be happy. See Misha's video of his first GT4 RS ride. They did an alignment at Manthey and show you the numbers -2.2 and -1.8. With stock tires this is likely to still be on the push side of neutral so I would go the full -.5 difference to the front axle. The Ring is different from pretty much any other 2-4 mile circuit that we will ever encounter. So my recommendation in your case would be to start out with:
Camber: -2.3/-1.8
Toe: 0 front and +12 min each side rear
Caster: no more than 9 degrees ( they need to adjust the LCA bushing after adding the front shim, we've seen that not happen before! )
Ride height:standard OEM to start @ 109/130 (When they add shim, it will lower the car a bit. It may be more off than you might think form the factory too. Each coilover turn is worth about 2mm in ride height)
See Misha's video for their camber recommendations which follow the same parameters that everyone I know uses (-.5 difference to start with). My toe numbers are within the above parameters. +2' then -2' equals 0 front. +10' then +2' equals +12' rear, you want stability in the rear. Drive the car, see what you think, and adjust from there. Three hundred dollar alignments are peanuts in the scheme of things for tracking your car.
Misha's video (at 3:50)
Last edited by lovetoturn; 08-02-2024 at 07:59 PM.
#1188
Three Wheelin'
#1189
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Always a recommendation, after a few events/sessions. How many events had that tyre completed?
Did you take a picture of the tyre…would be interesting to see general state of tyre.
Last edited by TDT; 08-03-2024 at 12:15 AM.
#1190
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Only reason the tyre is falling apart with -3.2 camber is over driving the car.
you must be on wot while it is pushing at a guess over heating and scrubbing the tyre.
so you need to be slower on the throttle out the bends a and feel what the car is telling you.
I was not killing my tyre with oem geo, now I am on -2.7 front and yes it still pushes but I don’t force it to a point my tyres being wrecked I just feed the power in.
i have no parts on my car to get -2.7/-2.2 and can get 4mm total toe.
caster is ok above 9 it helps give you more camber in the bends. People saying go below 9 seems odd to me.
more caster gives you more mid bend camber on a strut. And more steering response a win win side effect.
keep it below 10 not 9 ! But on the 4rs it has adjustable caster anyway. But don’t see a reason to have it below 9 !
fixes
1: drive to the geo
2: add front rebound
3: add rear bump
4: add a 9” front rim
5: add more rake.
6: add front aero
most of those require some adjustable shocks though. As you cannot add rake due to the bouncing rear which my car don’t really do after lowering the rear.
if you are getting turn in understeer, you need to again slow down and trail brake more. I am only getting understeer out the bends on wot. If you are getting turn in under steer with -3.2 you are going into the bend too fast with no trail.
sorry to say killing tyres is driver error. Never killed a tyre in my life. The other day at Donny was close to wreking front, but was the hottest day of the year and on a few laps I was pushing the tyre a bit out the bend, but after two laps I rained it in a bit you can feel a tyre push.
the cups cannot do 30oc air temps on hot track for more than 5 laps. Hence the USA guys like Dunlops more.
i like cups more but it’s not normally 30oc. Once my cups are done, that should be heat cycles over wear. I will fit A052 on a 9” front.
i don’t think you can fully dial in a 4rs without at least 2 way coilovers. You can then adjust front rebound and add rake to the car, which I hope would then not need a 255 tyre. A 991.2 gt3 don’t under steer on a 245, but it did have a 9” front wheel ! But you could add a lot more rake with no neg effect.
remember the cars need to be set up to understeer bias over over steer. So a car will always understeer if you over drive it esp one with more power as it adds to the effect when maybe a non RS GT4 would not do it as less power out the bends so less front end lift ie the car not squatting under wot lifting the front tyres off the ground.
all imo of course :-)
you must be on wot while it is pushing at a guess over heating and scrubbing the tyre.
so you need to be slower on the throttle out the bends a and feel what the car is telling you.
I was not killing my tyre with oem geo, now I am on -2.7 front and yes it still pushes but I don’t force it to a point my tyres being wrecked I just feed the power in.
i have no parts on my car to get -2.7/-2.2 and can get 4mm total toe.
caster is ok above 9 it helps give you more camber in the bends. People saying go below 9 seems odd to me.
more caster gives you more mid bend camber on a strut. And more steering response a win win side effect.
keep it below 10 not 9 ! But on the 4rs it has adjustable caster anyway. But don’t see a reason to have it below 9 !
fixes
1: drive to the geo
2: add front rebound
3: add rear bump
4: add a 9” front rim
5: add more rake.
6: add front aero
most of those require some adjustable shocks though. As you cannot add rake due to the bouncing rear which my car don’t really do after lowering the rear.
if you are getting turn in understeer, you need to again slow down and trail brake more. I am only getting understeer out the bends on wot. If you are getting turn in under steer with -3.2 you are going into the bend too fast with no trail.
sorry to say killing tyres is driver error. Never killed a tyre in my life. The other day at Donny was close to wreking front, but was the hottest day of the year and on a few laps I was pushing the tyre a bit out the bend, but after two laps I rained it in a bit you can feel a tyre push.
the cups cannot do 30oc air temps on hot track for more than 5 laps. Hence the USA guys like Dunlops more.
i like cups more but it’s not normally 30oc. Once my cups are done, that should be heat cycles over wear. I will fit A052 on a 9” front.
i don’t think you can fully dial in a 4rs without at least 2 way coilovers. You can then adjust front rebound and add rake to the car, which I hope would then not need a 255 tyre. A 991.2 gt3 don’t under steer on a 245, but it did have a 9” front wheel ! But you could add a lot more rake with no neg effect.
remember the cars need to be set up to understeer bias over over steer. So a car will always understeer if you over drive it esp one with more power as it adds to the effect when maybe a non RS GT4 would not do it as less power out the bends so less front end lift ie the car not squatting under wot lifting the front tyres off the ground.
all imo of course :-)
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TDT (08-03-2024)
#1191
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Only reason the tyre is falling apart with -3.2 camber is over driving the car.
you must be on wot while it is pushing at a guess over heating and scrubbing the tyre.
so you need to be slower on the throttle out the bends a and feel what the car is telling you.
I was not killing my tyre with oem geo, now I am on -2.7 front and yes it still pushes but I don’t force it to a point my tyres being wrecked I just feed the power in.
i have no parts on my car to get -2.7/-2.2 and can get 4mm total toe.
caster is ok above 9 it helps give you more camber in the bends. People saying go below 9 seems odd to me.
more caster gives you more mid bend camber on a strut. And more steering response a win win side effect.
keep it below 10 not 9 ! But on the 4rs it has adjustable caster anyway. But don’t see a reason to have it below 9 !
fixes
1: drive to the geo
2: add front rebound
3: add rear bump
4: add a 9” front rim
5: add more rake.
6: add front aero
most of those require some adjustable shocks though. As you cannot add rake due to the bouncing rear which my car don’t really do after lowering the rear.
if you are getting turn in understeer, you need to again slow down and trail brake more. I am only getting understeer out the bends on wot. If you are getting turn in under steer with -3.2 you are going into the bend too fast with no trail.
sorry to say killing tyres is driver error. Never killed a tyre in my life. The other day at Donny was close to wreking front, but was the hottest day of the year and on a few laps I was pushing the tyre a bit out the bend, but after two laps I rained it in a bit you can feel a tyre push.
the cups cannot do 30oc air temps on hot track for more than 5 laps. Hence the USA guys like Dunlops more.
i like cups more but it’s not normally 30oc. Once my cups are done, that should be heat cycles over wear. I will fit A052 on a 9” front.
i don’t think you can fully dial in a 4rs without at least 2 way coilovers. You can then adjust front rebound and add rake to the car, which I hope would then not need a 255 tyre. A 991.2 gt3 don’t under steer on a 245, but it did have a 9” front wheel ! But you could add a lot more rake with no neg effect.
remember the cars need to be set up to understeer bias over over steer. So a car will always understeer if you over drive it esp one with more power as it adds to the effect when maybe a non RS GT4 would not do it as less power out the bends so less front end lift ie the car not squatting under wot lifting the front tyres off the ground.
all imo of course :-)
you must be on wot while it is pushing at a guess over heating and scrubbing the tyre.
so you need to be slower on the throttle out the bends a and feel what the car is telling you.
I was not killing my tyre with oem geo, now I am on -2.7 front and yes it still pushes but I don’t force it to a point my tyres being wrecked I just feed the power in.
i have no parts on my car to get -2.7/-2.2 and can get 4mm total toe.
caster is ok above 9 it helps give you more camber in the bends. People saying go below 9 seems odd to me.
more caster gives you more mid bend camber on a strut. And more steering response a win win side effect.
keep it below 10 not 9 ! But on the 4rs it has adjustable caster anyway. But don’t see a reason to have it below 9 !
fixes
1: drive to the geo
2: add front rebound
3: add rear bump
4: add a 9” front rim
5: add more rake.
6: add front aero
most of those require some adjustable shocks though. As you cannot add rake due to the bouncing rear which my car don’t really do after lowering the rear.
if you are getting turn in understeer, you need to again slow down and trail brake more. I am only getting understeer out the bends on wot. If you are getting turn in under steer with -3.2 you are going into the bend too fast with no trail.
sorry to say killing tyres is driver error. Never killed a tyre in my life. The other day at Donny was close to wreking front, but was the hottest day of the year and on a few laps I was pushing the tyre a bit out the bend, but after two laps I rained it in a bit you can feel a tyre push.
the cups cannot do 30oc air temps on hot track for more than 5 laps. Hence the USA guys like Dunlops more.
i like cups more but it’s not normally 30oc. Once my cups are done, that should be heat cycles over wear. I will fit A052 on a 9” front.
i don’t think you can fully dial in a 4rs without at least 2 way coilovers. You can then adjust front rebound and add rake to the car, which I hope would then not need a 255 tyre. A 991.2 gt3 don’t under steer on a 245, but it did have a 9” front wheel ! But you could add a lot more rake with no neg effect.
remember the cars need to be set up to understeer bias over over steer. So a car will always understeer if you over drive it esp one with more power as it adds to the effect when maybe a non RS GT4 would not do it as less power out the bends so less front end lift ie the car not squatting under wot lifting the front tyres off the ground.
all imo of course :-)
I guess the same with camber … you wanted to go for MR set-up, and you ended up with -2.7 on the front.
In a few months, you will fit 255 and 305…
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
Last edited by 7184RS; 08-03-2024 at 05:24 AM.
#1192
#1193
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you need to side them L-R to help the set last.
Last edited by TDT; 08-03-2024 at 05:33 AM.
#1194
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I won’t be fitting Cup 2 s when I replace them but something like Yokohamas AO 52 s instead which are much less prone to wear the front shoulders. I’ ve done four Anglesey track days with the Cups which is well known to be hard on the front left tyre.
#1195
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Didn't you say that going for R compound tires were stupid just to gain 2 seconds on track, they were expensive bla bla bla... now you are after a set of A052 (expensive as **** tires)... LOL
I guess the same with camber … you wanted to go for MR set-up, and you ended up with -2.7 on the front.
In a few months, you will fit 255 and 305…![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
I guess the same with camber … you wanted to go for MR set-up, and you ended up with -2.7 on the front.
In a few months, you will fit 255 and 305…
![Wink](https://rennlist.com/forums/images/smilies/wink.gif)
my geo was the max I could have with no parts, when I went in that was the goal, see what the rear would do with 4mm total toe and add 0.5 to the front more. Ended up better and higher than I thought, too many people and Porsche UK settings said these figures were not possible. But they were. So that’s why I sort of said MR on those leaked sheets doing the rounds, but the goal was always max it out with no parts. Forums + people and 1/2 UK race shops don't seem to be able to get these higher number with 4mm total toe. So don't follow the sheep. The 4rs has been out 2 seasons now, so no idea why these lower geo figures are being set in stone, a few have now posted up more is possible on an oem car. So again some times you have to find out for yourself over forums and some less good geo shops. look what manifold was told above again BY PORSCHE Why ? It’s bull****.
Last edited by mrd_spy; 08-03-2024 at 06:35 AM.
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Taffy66 (08-03-2024)
#1196
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Same thing here. I’ll fit AO 52s probably in OEM sizes as I don ‘t want to lose the unsprung benefits of the standard Mags. You can buy a full set of AO 52s for £1360 here in the Uk. Will stick with standard PASM for now but will look for better dampers before next year. I’d love to fit some Ohlims TTXs but don’t want to lose the FAL because my garage has a inclined entrance.
If I had much deeper pockets I’d go all the way and fit the full Manthey Kit and ST brakes but at a silly £80k I’d be better off just switching to a 992 RS which is just perfect out of the box.
If I had much deeper pockets I’d go all the way and fit the full Manthey Kit and ST brakes but at a silly £80k I’d be better off just switching to a 992 RS which is just perfect out of the box.
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mrd_spy (08-03-2024)
#1197
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Shocks tyres and pads is a great start enough for 90% people.
I like you need lift my drive way demands it :-( so rules out TTX.
i would like SSR more ie 1st choice , but might go MCS knowing I can resell them on rennlist very easy later on.
selling a set of kw SSR might not get me the same return and be a tougher sell as selling a set of MCS.
UPS back to the USA is only 3 working days, the MCS would maybe a lower net cost over all once done. I am sure people would pay $4k 2nd hand for duddon MCS shocks with only 6 or 7 tracks days on them as I cannot see me keeping the 4rs into 2026.
I like you need lift my drive way demands it :-( so rules out TTX.
i would like SSR more ie 1st choice , but might go MCS knowing I can resell them on rennlist very easy later on.
selling a set of kw SSR might not get me the same return and be a tougher sell as selling a set of MCS.
UPS back to the USA is only 3 working days, the MCS would maybe a lower net cost over all once done. I am sure people would pay $4k 2nd hand for duddon MCS shocks with only 6 or 7 tracks days on them as I cannot see me keeping the 4rs into 2026.
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TDT (08-03-2024)
#1198
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With the MCS you’ll probably want top hats front and rear as MCS damper doesn’t come with as standard…. you’ll need to reuse OEM or if buying from Dundon, get their parts put on before shipping.
I’m sure @Jamie@dundonmotorsports will be happy to quote you with the appropriate package.
I’m sure @Jamie@dundonmotorsports will be happy to quote you with the appropriate package.
#1199
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Yep the kit is everything needed.
#1200
Three Wheelin'
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Higher caster numbers can work with OEM tires and wheels, but with larger after market tire and wheel combos and camber into the 3s, not so much. They will rub, so the wheel needs to be closer to the center, which is why I say to keep it around 9. Yes you gain some camber on turn in, but we never really turn the wheel that when at speed. Then there is the fact that some despise the feeling of the car when the camber is say 9.5 to 10. So it depends on what you have done to your car as to where you want to land. Porsche put the solid adjustable LCA bushings (caster pucks) on the car for a reason. Make your alignment tech use them if needed to get the caster number where you want. I would not call out a number for caster until you have a reading on where the car has been set from the factory or the last alignment. Adjust from there accordingly, or keep it the same. It is a game day decision.
As mrd says most people kill their tires by overdriving them. Learn to drive on the edge of the grip that you have and don't just grind your tires into the turn. The beginners need to learn to just push the car a little harder, and the intermediates sometimes need to back off a touch to preserve their tires. Look at what George Russel did at Spa.
Jason Hart has told us that the car ultimately needs more front end ... as much as you can get. So bigger front tires, bigger wheels, geo, aero, rake. The front end is the rate limiting step here. Get as much front end as you can and then balance it to the rear. Now this is a paid professional race driver talking, and the actual things that need to be done may be too extreme for most people here. But the general idea is such and does not change for anyone at their respective level. Porsche gave the car a fair amount of understeer from the factory to keep people out of trouble and not let it get too close to the 992 GT3. Again refer to Misha's comments about the car before and after he drove the SSR.
As mrd says most people kill their tires by overdriving them. Learn to drive on the edge of the grip that you have and don't just grind your tires into the turn. The beginners need to learn to just push the car a little harder, and the intermediates sometimes need to back off a touch to preserve their tires. Look at what George Russel did at Spa.
Jason Hart has told us that the car ultimately needs more front end ... as much as you can get. So bigger front tires, bigger wheels, geo, aero, rake. The front end is the rate limiting step here. Get as much front end as you can and then balance it to the rear. Now this is a paid professional race driver talking, and the actual things that need to be done may be too extreme for most people here. But the general idea is such and does not change for anyone at their respective level. Porsche gave the car a fair amount of understeer from the factory to keep people out of trouble and not let it get too close to the 992 GT3. Again refer to Misha's comments about the car before and after he drove the SSR.