MikeR397's Porsche Turbo
#47
08-28-2010 | 01:22 PM
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I had Porsche reset the sensor ($60) and that didn't change anything. The car still applys breaking to the inside wheels when cornering on highway exit ramps at speeds over ~45-50mph, even though there is definately no slip. I do have mismatched tires (PS2 in front, Nitto Invos in back), but they are only .3 inch off in diameter which should not be the problem, and I really don't want to buy new tires prematurely. The problem isn't that big of one, but occasionally its an annoyance since I can't really push the car's handeling capabilities. Please let me know if you have any thoughts on the matter.
I would imagine it is due to the .3" difference in diameter. .3" in diameter will calculate to about one inch difference in circumference. That difference in circumference will cause the tires to rotate at different a different RPM. You take a high speed turn, PSM senses the tires spinning at different speeds, thinks its slip and tries to save you by applying the brake(s).
#49
08-28-2010 | 06:37 PM
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Just a $45 ticket for having a radar in VA. Pathetic.
#50
08-28-2010 | 06:41 PM
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I would imagine it is due to the .3" difference in diameter. .3" in diameter will calculate to about one inch difference in circumference. That difference in circumference will cause the tires to rotate at different a different RPM. You take a high speed turn, PSM senses the tires spinning at different speeds, thinks its slip and tries to save you by applying the brake(s).
Last edited by MikeR397; 08-28-2010 at 06:43 PM.
#51
09-14-2010 | 06:17 PM
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I removed the ugly rear windshield wiper; the car looks much cleaner without it, and I think you notice that classic 911 shape even more without that ugly thing sticking up. The plug cost $42 shipped and came with instructions (feel free to PM me if you want to know where I got it; I don't think I'm allowed to post that info?) The process took about 25-30 minutes total, but if I had the right size tools, you could do it in half the time.
Sorry for the night pics, I can take pics tomorrow in the daylight if anyone wants them. I think this $42 mod is definately worth it.
Sorry for the night pics, I can take pics tomorrow in the daylight if anyone wants them. I think this $42 mod is definately worth it.
#54
09-15-2010 | 06:13 AM
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#55
09-15-2010 | 11:26 AM
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I don't mean to be coy, I'm just not clear what stuff for sale we can post here and what we can't. I posted about some gas cards I was considering selling, it wasn't even a for sale post, just a "see if anyone is interested" post, and was told by the mods after they deleted my post that I'd have to become a site vendor for $350 a month to post like that. I've also seen other people only PM links to products even when for sale from a third party, so I wasn't sure.
#56
10-28-2010 | 11:43 PM
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Today was the first moderately cold day I'd had the car since I bought it in May, about mid forties. It seemed the car had some extra juice with the cold air today 
. I had PSM off and was really enjoying the hell out of myself today. I'm really getting addicted to breaking grip and AWD power sliding around any place I've got a reasonable margin of error to work with 
. My G35 Coupe can do a nice power slide too, with a "measly 285hp" compared to the Porsche's ~525hp, but being RWD in the G35, I'm always concerned about spining the thing around; the Porsche is just so controllable, just insanely precise and easy to control while out of control. For the first time, I can say I'm looking forward to it getting colder...
Something tells me I'm going to need a new set of tires before next summer...
. I had PSM off and was really enjoying the hell out of myself today. I'm really getting addicted to breaking grip and AWD power sliding around any place I've got a reasonable margin of error to work with . My G35 Coupe can do a nice power slide too, with a "measly 285hp" compared to the Porsche's ~525hp, but being RWD in the G35, I'm always concerned about spining the thing around; the Porsche is just so controllable, just insanely precise and easy to control while out of control. For the first time, I can say I'm looking forward to it getting colder...Something tells me I'm going to need a new set of tires before next summer...
Last edited by MikeR397; 10-28-2010 at 11:48 PM.
#57
10-29-2010 | 05:50 AM
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Hey Mike,
I responded to you on a different thread, too. I'm having the exact same PSM problem with my 315-25-19 Invos and 235-35-19 (4 yr old) PS2s. Interestingly enough, I had no PSM trouble when I was running the same PS2s, but 305-30-19 Hankook Ventus tires in the rear. The problem showed up when I switched to the Invos.
I have read about at least one 996 TT owner who solved this problem by buying new Invos up front.
I responded to you on a different thread, too. I'm having the exact same PSM problem with my 315-25-19 Invos and 235-35-19 (4 yr old) PS2s. Interestingly enough, I had no PSM trouble when I was running the same PS2s, but 305-30-19 Hankook Ventus tires in the rear. The problem showed up when I switched to the Invos.
I have read about at least one 996 TT owner who solved this problem by buying new Invos up front.
#58
10-29-2010 | 06:59 AM
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Now if I can just figure out how to fix this steering angle sensor problem that triggers PSM around fast/aggressive corners due to the 997tt wheels even when they are not slipping at all. Tym at Switzer said that he had another customer have the same PSM steering angle sensor problem with 997tt wheel upgrades, and no solution has been found; although I know this is such a common mod and I haven't read much about the problem elseware. I had Porsche reset the sensor ($60) and that didn't change anything. The car still applys breaking to the inside wheels when cornering on highway exit ramps at speeds over ~45-50mph, even though there is definately no slip. I do have mismatched tires (PS2 in front, Nitto Invos in back), but they are only .3 inch off in diameter which should not be the problem, and I really don't want to buy new tires prematurely. The problem isn't that big of one, but occasionally its an annoyance since I can't really push the car's handeling capabilities. Please let me know if you have any thoughts on the matter.
#59
10-29-2010 | 07:03 AM
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rosesplus,
I have heard several explanations for this problem. Many claim that it is the steering angle sensor (hard to see how the sensor could get out of whack). Some think it can be fixed by cleaning up the Hall effect sensors at each wheel (which tend to get gummed up with metal / magnetic bits). Some think mismatched rubber. I have found no repeatable, solid fix to this issue. It's kinda scary when it happens.
I have heard several explanations for this problem. Many claim that it is the steering angle sensor (hard to see how the sensor could get out of whack). Some think it can be fixed by cleaning up the Hall effect sensors at each wheel (which tend to get gummed up with metal / magnetic bits). Some think mismatched rubber. I have found no repeatable, solid fix to this issue. It's kinda scary when it happens.
#60
10-31-2010 | 08:43 PM
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For some reason, I have not had the PSM problem lately, although I do drive a bit more carefully around the corners knowing it could occur. I've also been more aggressive and put some wear on all my tires (including the new Nitto Invo's in the rear), so maybe that is it. For now, its not that big of a deal that I can't just wait until the front PS2's wear out and I"ll put Invo's on the front and hopefully the problem will be 100% gone. It definately is very unsettling when it happens.