jadatis

Tire pressure advice is all about load on the tyre and speed you drive with. I registerd to this forum to give you an answer, and I think,give usefull information. Dont have a Porche, so wont introduce myself in a seperate topic. Once got hold of the formula , the European tire-makers use for decades,and the American since 2006 for standard load and XL. The pressures you write are for maximum load, and rear even maximum overload or shifted load R/L,For maximum speed of the car, so are even for on the road with only driver and a little load, much to high. This is only for the tire-maker, so he wont get a law sute when someone,goes to the edges of what is possible. I must say that for tires with low aspect-ratio ( 235/40 ZR 18 92Y XL for instance the bold part) I have my doubts about the calculation of the maximum load the tire makers do, so there you better be on the extra save side. If you first calculate the needed pressure for the weights you use when driving , and then fill it in another spreadsheet of mine, you will get the pressure you have to fill cold , to get a warm pressure that is right for the race. Under here a link to my public map of Skydrive/hotmail. Click at the end of the line of the document or map you want to use on the I in a cirlcle. Then at the right barr the info appears about it. Click on Download, and after downloading open spreadsheets in Excel or compatible programm to work with it. In the browser wont work because it cant handle some things I used in them.r You need the map "recalculating tyre-pressure" (7th map) and spreadsheet 1 from the bottom "pressurecalcution with temp" . https://skydrive.live.com/?cid=a526e0eee092e6dc#cid=A526E0EEE092E6DC&id=A526E0EEE092E6DC%21128 If you cant figure it out yourselves, give me here the details needed, and I will do it for you as an example. Greatings from Holland. Peter