Toyo Proxes R: handling & pressure
Discussion
Before I had Toyo Proxes T1-S's all around and the handling was superb.
Now I have T1-R's at the rear and the handling is different: front feels lighter and in fast long corners the rear feels less stable. The R's are supposed to have a stiffer wall.
I'm running 23 psi at the front and 25 psi at the rear (same as with the T1-S's). The R's have now done some 700 miles. Together with the new tyres I've had my engine done which is now producing some 100 bhp/torque more than my (worn) engine, which affects the handling too, I guess.
What should I change: increase/decrease pressure fronts or increase/decrease rears?
Or are the R's still bedding in and should I be patient?
thanks guys.
Now I have T1-R's at the rear and the handling is different: front feels lighter and in fast long corners the rear feels less stable. The R's are supposed to have a stiffer wall.
I'm running 23 psi at the front and 25 psi at the rear (same as with the T1-S's). The R's have now done some 700 miles. Together with the new tyres I've had my engine done which is now producing some 100 bhp/torque more than my (worn) engine, which affects the handling too, I guess.
What should I change: increase/decrease pressure fronts or increase/decrease rears?
Or are the R's still bedding in and should I be patient?
thanks guys.
I would fit the T1-R to the front as well. Not keen on having two different tyres front/rear with obvious differeing characteristics.
I've got T1-S tyres on my BMW and have nothing but praise for them. They are almost down to the canvas now but the T1-S is still available if you search.
Experiment with the pressures a little.
Just read your other post regarding your substantial increase in power.
I think your T1-S rears would have behaved differently with all that extra torque.
Sometimes it is better to change one thing at a time.
>> Edited by Aaron C. Reskew on Sunday 5th June 14:01
I've got T1-S tyres on my BMW and have nothing but praise for them. They are almost down to the canvas now but the T1-S is still available if you search.
Experiment with the pressures a little.
Just read your other post regarding your substantial increase in power.
I think your T1-S rears would have behaved differently with all that extra torque.
Sometimes it is better to change one thing at a time.
>> Edited by Aaron C. Reskew on Sunday 5th June 14:01
Aaron C. Reskew said:
I would fit the T1-R to the front as well. Not keen on having two different tyres front/rear with obvious differeing characteristics.
I've got T1-S tyres on my BMW and have nothing but praise for them. They are almost down to the canvas now but the T1-S is still available if you search.
Experiment with the pressures a little.
Just read your other post regarding your substantial increase in power.
I think your T1-S rears would have behaved differently with all that extra torque.
Sometimes it is better to change one thing at a time.
>> Edited by Aaron C. Reskew on Sunday 5th June 14:01
I know, I wanted T1-S's but they were unavailable at that time; and I didn't want some local French Renault garage doing my tyres, so I went for the R's.
I had T1-Rs on the Chimaera after they were highly regarded on PH. They took about 700 miles to wear in (throughout which they were extremely on edge) and when they did wear in they were only slightly less crap. The car did not handle well on them at all. Not sure why anyone recommends them, total pile of shite.
gerjo said:
What should I change: increase/decrease pressure fronts or increase/decrease rears?
Or are the R's still bedding in and should I be patient?
Given those perameters then I'd say try 2 or 3 psi less at the rear but given your engine changes the rear answer is to look at your spring rates and that also means thinking about dampers. Have you read www.pistonheads.com/gassing/topic.asp?h=0&f=8&t=183730 ?
19560 said:
Given those perameters then I'd say try 2 or 3 psi less at the rear but given your engine changes the rear answer is to look at your spring rates and that also means thinking about dampers. Have you read www.pistonheads.com/gassing/topic.asp?h=0&f=8&t=183730 ?
I'll try less at the rear (thought of increasing it myself, but I'll try both). What about the dampers? I have fully adjustable Koni's especially designed for the Griff; they have been absolutely brilliant so far. I did one click softer on all dampers when I moved to France because of all the nice but sometimes bit bumpy small roads over here; should I go a click firmer on the rear now with all the extra power?
gerjo said:
Given those perameters then I'd say try 2 or 3 psi less at the rear but given your engine changes the rear answer is to look at your spring rates and that also means thinking about dampers. Have you read <a href="www.pistonheads.com/gassing/topic.asp?h=0&f=8&t=183730">www.pistonheads.com/gassing/topic.asp?h=0&f=8&t=183730</a> ?
I'll try less at the rear (thought of increasing it myself, but I'll try both). What about the dampers? I have fully adjustable Koni's especially designed for the Griff; they have been absolutely brilliant so far. I did one click softer on all dampers when I moved to France because of all the nice but sometimes bit bumpy small roads over here; should I go a click firmer on the rear now with all the extra power?
What spring rates are you running? You will need stiffer than standard IMHO.
I went down this route some years ago.
Tried AVO's (crap). Took them off within days of fitting them.
Nitron are about the best as there has been a lot of development work with TVR's gone into their production.
My car was overdamped and undersprung.
The Nitrons have had many changes over a short period. I seem to remember reading somewhere that there is now a 7th version of the original damper suited to the Griff/Chimaera.
It all depends on what you are aiming for. Comfortable general use or serious track work, you cannot compromise.
Haven't got a clue what spring rates I'm running. Car was originally set up by the Koni Race Department in Holland; it was actually my car they used to develop the special dampers for the Griff. These Koni's are the Dutch equivalent to Nitrons.
Isn't 22 psi at the rear too low in terms of risking that the tyre seperates from the wheel?
Big M: Good to hear you are satisfied with the R's. What pressures are you running front/rear?
>> Edited by gerjo on Monday 6th June 07:45
Isn't 22 psi at the rear too low in terms of risking that the tyre seperates from the wheel?
Big M: Good to hear you are satisfied with the R's. What pressures are you running front/rear?
>> Edited by gerjo on Monday 6th June 07:45
Aaron C. Reskew said:
I would try and find out what springs they used.
Interesting one on the Koni's. How much and what are they made from etc?
I'll try to find out.
Spoke to Austec yesterday; they said the back seems to lack grip. Could be tyres are still not fully bedded in. I remember the Toyo S´s also took ages. Must try a lower tyre pressure and/or damper setting at the rear. If that doesn't help, more camber (can't do that myself).
The Koni´s are top of the range dampers. Don´t know exactly what they are made from. I bought them a few years ago so I don´t know the current pricetag but should be around EUR 400 to 500 a piece.
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