Has anyone experimented with pressures?
The other question I had was once you have been out and the tyres have warmed up do you re-adjust the pressures?
Cheers Jamie
I think that was discussed recently, try a search.
Ian
28 HOT is a good place to start.
I was given a message from god that 28 hot was good.
I was given a message from god that 28 hot was good.
When did you last hear from her, & what else was said?
quote]I was given a message from god that 28 hot was good
The pressure is a result of the heat of the tyre and the air or other gas inside. What temperature should we run at is the question? . Playing with pressures and not knowing the actual resulting running temp.of the rubber seems daft. if the track temp is higher or more hard curves etc. the pressure goes up, so one could reduce the pressure down to 28 hot again. but do the tyres have an optimal operational temperature. surely a tyre temp gauage would be worth investing in to optimise the grip and life of those expensive 038’s?
Hint: measure temperature across the surface with a pyrometer.
The part of the tyre that is hotter is working more.
If one assumes a coorect geo setup (very important, could change everything), and to optimize the tyre contact patch, if the middle is hotter than the sides, let air out.
If sides are hotter than middle put air in.
If you are running a lot of negative camber though, maybe it would be better to assume that the inside of the tyre is going to run hotter than the outside? (Coz it is pressing down more on the surface?)
So is it more likely that the best set up is going to be, say, hottest on the inside, coolest on the outside, with the middle somewhere in between?
Or am I talking bollox?
If you are running a lot of negative camber though, maybe it would be better to assume that the inside of the tyre is going to run hotter than the outside? (Coz it is pressing down more on the surface?)
So is it more likely that the best set up is going to be, say, hottest on the inside, coolest on the outside, with the middle somewhere in between?
Or am I talking bollox?
Nope, no bollox there, thats correct .
If you are running a lot of negative camber though, maybe it would be better to assume that the inside of the tyre is going to run hotter than the outside? (Coz it is pressing down more on the surface?)
So is it more likely that the best set up is going to be, say, hottest on the inside, coolest on the outside, with the middle somewhere in between?
Or am I talking bollox?
Nope, no bollox there, thats correct .
but camber is only there to optimise the contact patch in loaded corner conditions, therefore if there is too much camber one would never achieve the grip to initiate the movement in tyre and suspension to achieve this optimal cornering contact. it might be sort of slightly complicated…
Balancing pressures all round when hot on the track also helps alot, do 2-3 laps come in balance pressures and i am sure you will be quite surprised at the difference in balance of the car. It helps to account for predominantly clockwise or anti clockwise corners. And a more even wear rate.
The ambient temp here is propably alot hotter than on your side of the world, with outside air temp of 30 degrees and reasonably warm track temps i balance to 29.5 all round and on colder days and in winter to 28.
If you are running a lot of negative camber though, maybe it would be better to assume that the inside of the tyre is going to run hotter than the outside? (Coz it is pressing down more on the surface?)
So is it more likely that the best set up is going to be, say, hottest on the inside, coolest on the outside, with the middle somewhere in between?
Or am I talking bollox?
Nope, no bollox there, thats correct .
That is correct, but then you might have the car setup with a lot of camber for a specific turn(s) in a circuit and most of the rest is flat so yes, the inside will be warmer and it should be.
OTOH, you might have the same camber on a very twisty circuit (no straights)where the tyres are always loaded and the temp would be more or less even.
It all depends…
Best way is with a temperature guage but you can do it purely from tyre pressure… which is how many of us do it and it does make a difference - generally when the pressure is too much the grip is too little.
If using a temperature guage and you have plenty -ve camber a 10 degree difference from inside to outside is in the correct ball-park… but its a pretty much a trial and error thing if your a layman like me…
More important than temp/pressure is to carefully inspect the tyres. How they are wearing gives you loads of info.
My car has 3deg neg camber at the rear, and the inside of the tyre is 10degc hotter, cooling to the outer. I think this is a bit much, but its how the car was when I picked it up. From my caterham days we tried to get an even temp across the tyre, so I may remove some camber and play about a bit. I’m on std suspension though, so I guess the neg camber is there to take up the lean. Get your Demon twonks catalogue out and order a pyrometer and a camber gauge, it stops the random guesswork. I put them on my christmas list one year
Oh, and while you’re at it, order Alan Stanniforths Comptetition car suspension book. ISBN 1 85960 664 X
Its published by Haynes (of manuals fame)
It’s a bit deep, but a great read if you’re interested. I also have competed with Alan many times (he’s in his mid 70’s!!!) and he’s a star. He’s forgotten more about suspension than I could ever hope to know.