RFT to Non-RFT tire pressures?
- Thread starter javis20
- Start date
I'm running 32psi F/34psi R, feels excellent to me.
A
Anonymous
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Definitely don’t inflate to same pressure as RFT’s. I’m running at 34psi front, 36psi rear on my E89
javis20 said:
My experience with new tyres suggests they require a fair few miles to scrub and feel like they should. Leaving the tyre shop I had a poo-poo moment when I floored the car on a straight and the car went side ways. Basically they had less grip than my very bold tyres just out of the tyre shop. After a 20 mile hoon the tyres felt a lot better, but only got full confidence on them after 150 miles or so. Just keep in mind they have a lot less grip initially so push your car accordingly; in the beginning of my first hoon I was understeering everywhere.
Attleborough, Norfolk
EssexZed said:
Same as me, but I'm on 18s.
Tried 32/34 but felt like a small amount of initial roll in the tyre wall as I cornered. The extra 2psi has resolved that.
I suspect different makes of tyre, as well as wheel diameter, side wall depth etc will all have an effect, so you'll probably have to pick a figure to start with and work from there.
General consensus (though not all I notice) seems to be a 2psi stagger from front to rear.
lucasxdiniz said:
That'll be the release agent so they can get the tyres out of the moulds, scrubs off in a couple of miles usually, however the high negative camber on the rear of the Z4 does mean the outer edges take longer to scrub in.
I should add that my car has the following tire sizes...
225/40 R18 in the front
255/35 R18 in the back
Dealer has them inflated to 36 in the front and 40 in the back.
I switched from Bridgestone Potenza RE960AS RFT's to Michelin Pilot Sport A/S 3+ tires and BMW dealer did a 4 wheel alignment.
My complaint is lack of steering response. Feels like the steering is detuned, almost like driving an estate wagon. However, the tires are quieter and ride is smoother, like an estate wagon.
225/40 R18 in the front
255/35 R18 in the back
Dealer has them inflated to 36 in the front and 40 in the back.
I switched from Bridgestone Potenza RE960AS RFT's to Michelin Pilot Sport A/S 3+ tires and BMW dealer did a 4 wheel alignment.
My complaint is lack of steering response. Feels like the steering is detuned, almost like driving an estate wagon. However, the tires are quieter and ride is smoother, like an estate wagon.
A
Anonymous
Guest
javis20 said:
What car, what size wheels / tyres, why tyres?
javis20 said:
I think I know what you mean
On a previous Z4 (E85 3.0l) I swapped the runflats that were atrocious on that car, to a set of Vredestein Sessantas - the quality ride, roadholding and tramlining were much improved but the steering felt as tho there was a lag. It was as if the sidewalls had to take up the flex before anything happened. They were inflated to the Vredestein recommended / greatly increased pressures.
It just did not feel as sharp!
I suppose that’s why I’ve dragged my heals in making the change on the current car.
A
Anonymous
Guest
javis20 said:
36/38 been used on Michelin PS4 and Continental Sport 5 in your sizes with an appropriate trade off..
A
Anonymous
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ronk said:Pbondar said:...with an appropriate trade off..
I’m not sure what you mean?
Comfort, steering feel, ride etc
Pbondar said:ronk said:Pbondar said:...with an appropriate trade off..
I’m not sure what you mean?
Comfort, steering feel, ride etc
I understand
The E85 was improved in all respects other than that initial turn in lag - Im now wondering if my 35is will feel the same?
There are many on here that say the E89 is not the best of chassis for the big lump of engine but that is tempered by the condemnation of the runflats and the improvements that conventional rubber brings.
A
Anonymous
Guest
Handling is such a complex subject..compounded by people’s preferences, biases and lack of comparative benchmarks plus where people spend their time in their cars..
So if you’re happy in the nicest sense who cares...
It’s clear that you can alter many attributes to change various aspects..
Obviously weight distribution isn’t so easy with the big heavy lump of the 35i with a lot of weight over / in front of the axle compared to the N20 engines cars..
The amount of power and how it affects the chassis are again complex variables..
When I started I was shocked at how ‘poor’ the car I have was..but I’ve changed wheels/tyres/arbs/dampers/steering parts/LSD and I’ve got used to it after 3 years and 15k miles of hard driving in unconstrained environments..
So I’m happy..I wouldn’t change it for anything apart from maybe an Atacama Yellow 35 and based on past experience may regret it..
Maybe a 35i with lots of ‘my mods’ would be ok..certainly when I drove one two years ago I certainly didn’t like the handling one bit, the power was ok but it was more that there was too much power for the chassis rather than the joy of lots of power..I came with £17.5k in my pocket, took it for a drive and went home underwhelmed..
But each to their own...
Rambling mode off..not sure what that has to do with tyre pressure..
So if you’re happy in the nicest sense who cares...
It’s clear that you can alter many attributes to change various aspects..
Obviously weight distribution isn’t so easy with the big heavy lump of the 35i with a lot of weight over / in front of the axle compared to the N20 engines cars..
The amount of power and how it affects the chassis are again complex variables..
When I started I was shocked at how ‘poor’ the car I have was..but I’ve changed wheels/tyres/arbs/dampers/steering parts/LSD and I’ve got used to it after 3 years and 15k miles of hard driving in unconstrained environments..
So I’m happy..I wouldn’t change it for anything apart from maybe an Atacama Yellow 35 and based on past experience may regret it..
Maybe a 35i with lots of ‘my mods’ would be ok..certainly when I drove one two years ago I certainly didn’t like the handling one bit, the power was ok but it was more that there was too much power for the chassis rather than the joy of lots of power..I came with £17.5k in my pocket, took it for a drive and went home underwhelmed..
But each to their own...
Rambling mode off..not sure what that has to do with tyre pressure..
A
Anonymous
Guest
Pbondar said:Handling is such a complex subject..compounded by people’s preferences, biases and lack of comparative benchmarks plus where people spend their time in their cars..
So if you’re happy in the nicest sense who cares...
It’s clear that you can alter many attributes to change various aspects..
Obviously weight distribution isn’t so easy with the big heavy lump of the 35i with a lot of weight over / in front of the axle compared to the N20 engines cars..
The amount of power and how it affects the chassis are again complex variables..
When I started I was shocked at how ‘poor’ the car I have was..but I’ve changed wheels/tyres/arbs/dampers/steering parts/LSD and I’ve got used to it after 3 years and 15k miles of hard driving in unconstrained environments..
So I’m happy..I wouldn’t change it fior anything apart from maybe an Atacama Yellow 35 and based on past experience may regret it..
Maybe a 35i with lots of ‘my mods’ would be ok..certainly when I drove one two years ago I certainly didn’t like the handling one bit, the power was ok but it was more that there was too much power for the chassis rather than the joy of lots of power..I cane with £17.5k in my pocket, took it for a drive and went home underwhelmed..
But each to their own...
Rambling mode off..not sure what that has to do with tyre pressure..
Wise words! In the end it comes down to personal preference in terms of how you want the car to be. I changed to non RFT’s and couldn’t be happier. Immense improvement in comfort and much, much quieter, and as for steering, it still seems to go where I point it :lol: