Tyre Choice

[gribley]

I am looking towards putting 17" wheels on my Mk1 LS400

With the std well worn tyres my speedo is reading about 8% fast.

New tyres would be about 1.5% better ie 6.5% fast

If I fit 225/50/17 (+1.4%) speedo would be 5% fast

If I fit 225/55/17 (+5%) speedo would be 1.5% fast

If I fit 235/50/17 (+3%) speedo would be 3.5% fast

Would there be any problem using any of the above tyres My rims are GS300 10 spokes 7.5" x 17"

[steve-bedford]

All of those tryes should physically fit - You should try to keep within 2.5% if you can though. If nothing else, keep having to mentally recalculate your speed all the time would be painful.

My LS400 DHP originally had 245/50/17s (at a stupid price) so I swapped them for 235/55/17s which were less than half the price. They are nicer to ride on too as the profile is a little bigger but ultimately there is nothing in it and only a 1.99% difference.

In the meantime, you may find this link useful .....> http://www.lexusownersclub.co.uk/forum/lof...php/t37499.html

[thermoacc]

Hi,

I am running the 5-spoke GS300 wheels on my MK1 LS400. They are 8J 17" ,using 245/45/17 on them so making the speedo a tad behind (I think about 1.4% or so).

I would use the 235/50`s as wider tyres than the standard really make the drive so much better...actually adds a little response to the old bus`s steering which is no bad thing!

I wouldn't worry about the speedo too much...suggest using a good sat-nav and roll it down the m-way at 70, check where the speedo reads and making a note of the difference. Every car I have driven shows slower than actual speed and the lexus was around 4mph under using the standard wheel and tyre of 205/65/15.

[gribley]

Ive done the sat nav bit, speedo reading 76 @ 70, 54 @ 50 so its approx 8% fast

If Iknock off the 1.5% for worn tyres I'm still reading 6.5% fast