Tire Pressure - RDK
#17
Burning Brakes
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Goodrich is introducing a Protenza tire that fits our cars rears later this spring.
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Dan:
That's good news for all the D90 owners who want to keep there original wheels (and tire size) as long as possible. Like me!
Do you know in what model?
Just checked the Tire Rack site and the Potenza 225/50/16 go from 116$ (RE 760 Sport) to 220$ (RE 050RFT) each.
Billal:
If you want to keep the RDK system and open your tire choice, the 17" cup I is the way to go!
If you can get a set and are ready to put the extra $, do it.
That's good news for all the D90 owners who want to keep there original wheels (and tire size) as long as possible. Like me!
Do you know in what model?
Just checked the Tire Rack site and the Potenza 225/50/16 go from 116$ (RE 760 Sport) to 220$ (RE 050RFT) each.
Billal:
If you want to keep the RDK system and open your tire choice, the 17" cup I is the way to go!
If you can get a set and are ready to put the extra $, do it.
#20
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Bertrand: The Bridgestone rep did not state the model. He was making a big deal about how it fills an enthusiast market niche. I'm planning on purchasing a matched set of 4 of whatever model when they come out though. Apparently, that will take some deep pockets!
#22
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Our tires are designed to carry a specific load at a specific pressure. The Michelin 285 cup tires I ran on the rear were designed for 600 Kgs at 36 psi, thus they worked well at 24 psi carrying our 400 kgs assuming correct balance.
If you over inflate the centres will wear preferentially and I have seen that a lot over here probably becuase the hot temps just heat the wheel more than in Europe. For day to day running I use 32 psi on these rears nowadays and it seems to work well but it is probably more than I need and more than optimal for high load cornering.
As for RDK- I reckon it is useless to all intents and purposes and my experience is that to keep the light out you have to over rpessurise the tyres. I suspect Porsche worked this out and hence why they dropped it. Doubtless today's techology is far superior and more reliable. With the stock 16 inch wheels and tires on my late S4 it did not take me long [13 years ago] to work out the warning system was a nuisance and I quickly learned to ignore it.
Putting the jumper in and ignoring the system is the way to go and if you want to revert to stock it takes a matter of minutes to reverse.
Fred
If you over inflate the centres will wear preferentially and I have seen that a lot over here probably becuase the hot temps just heat the wheel more than in Europe. For day to day running I use 32 psi on these rears nowadays and it seems to work well but it is probably more than I need and more than optimal for high load cornering.
As for RDK- I reckon it is useless to all intents and purposes and my experience is that to keep the light out you have to over rpessurise the tyres. I suspect Porsche worked this out and hence why they dropped it. Doubtless today's techology is far superior and more reliable. With the stock 16 inch wheels and tires on my late S4 it did not take me long [13 years ago] to work out the warning system was a nuisance and I quickly learned to ignore it.
Putting the jumper in and ignoring the system is the way to go and if you want to revert to stock it takes a matter of minutes to reverse.
Fred
#23
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If you click the link below you'll see the tire pressure on this chart are directly proportional to the speed of the vehicle. On the table it is displaying a speed of 161mph to 42.5psi...
http://www.tirerack.com/tires/tirete....jsp?techid=72
I don't know if this applies to our cars but it looks suspiciously similar.
Dan
http://www.tirerack.com/tires/tirete....jsp?techid=72
I don't know if this applies to our cars but it looks suspiciously similar.
Dan
#26
Race Car
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I know this thread is older (and I searched) is there a way to retrofit the 18" tires I have with the RDK sensors? The system is disabled currently in my 91 S4.
Thanks!
Michael
Thanks!
Michael
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What about installing a modern stem-based system, but then feeding signals from its controller into the RDK controller? I.e. keep the monitoring and reporting functionality, but upgrade the sensor capabilities.
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I'm thinking of installing fixed resistors on the RDK control unit inputs instead of the four tire pressure sensors. This would avoid problems with faulty/over-sensitive sensors, as well as avoiding any problems with ABS diagnostic if the RDK unit is disconnected. (and jumped between pin 2 and 13)
The sensors seem to be connected to ground and the RDK unit, thus implying that they are pressure-controlled resistors.
I'd have to ohm a working sensor, and/or the voltage at the RDK sensor input to be able to choose the right resistor value.
Anyone tried this?
Cheers,
Tore
The sensors seem to be connected to ground and the RDK unit, thus implying that they are pressure-controlled resistors.
I'd have to ohm a working sensor, and/or the voltage at the RDK sensor input to be able to choose the right resistor value.
Anyone tried this?
Cheers,
Tore
#30
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I have 2 sets of 16' wheels and all the pressure sensors work on both sets of wheels.
There are two methods to set up the RDK, one is the short method described in the Owners Operation Manual and the long method is in the Technical Publication located in Jim Technical CD's IIRC.
I have no problems operating with the rear tyre pressure at Porsche recommended pressure and I have good "nearly flat" wear across the entire thread. I check my tread depth together with my ride height at each yearly service.
Tails 1990 928S4 Auto
There are two methods to set up the RDK, one is the short method described in the Owners Operation Manual and the long method is in the Technical Publication located in Jim Technical CD's IIRC.
I have no problems operating with the rear tyre pressure at Porsche recommended pressure and I have good "nearly flat" wear across the entire thread. I check my tread depth together with my ride height at each yearly service.
Tails 1990 928S4 Auto