Righto, I'm changing to F1s :mad:
#21
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Originally posted by Nick Graves
Chris,
Would you please elaborate on that acceleration bit?
Chris,
Would you please elaborate on that acceleration bit?
#22
Ah,
That's a bit counter-intuitive, as I thought.
I would have expected the overall rolling radius of the 18" to be greater, hence the car would be fractionally higher geared.
As you say, possibly the heavier wheels/tyres increases driveline inertia, resulting in a more sluggish feel.
I know what you meant about tyres feeling heavy. The MX-5s felt like they had walking boots on, if the incorrect tyres were fitted.
That's a bit counter-intuitive, as I thought.
I would have expected the overall rolling radius of the 18" to be greater, hence the car would be fractionally higher geared.
As you say, possibly the heavier wheels/tyres increases driveline inertia, resulting in a more sluggish feel.
I know what you meant about tyres feeling heavy. The MX-5s felt like they had walking boots on, if the incorrect tyres were fitted.
#23
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Originally posted by Nick Graves
Ah,
That's a bit counter-intuitive, as I thought.
I would have expected the overall rolling radius of the 18" to be greater, hence the car would be fractionally higher geared.
Ah,
That's a bit counter-intuitive, as I thought.
I would have expected the overall rolling radius of the 18" to be greater, hence the car would be fractionally higher geared.
#24
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Actually that was a complete lie.
I've just checked again, and it was 1.8mm MORE, now its 8.8mm more.
Which of course is a rolling radius of +0.9mm , and + 4.4mm.
I've just checked again, and it was 1.8mm MORE, now its 8.8mm more.
Which of course is a rolling radius of +0.9mm , and + 4.4mm.
#26
Originally posted by Fletch
Actually that was a complete lie.
I've just checked again, and it was 1.8mm MORE, now its 8.8mm more.
Actually that was a complete lie.
I've just checked again, and it was 1.8mm MORE, now its 8.8mm more.
#27
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No, that was in dia. -- 4.4mm radius.
Whats the sizes of the tyres GSI?
i.e.
Stock 245/45/16 = Radius 313.5mm
New 255/35/18 = Radius 317.9mm
which is 1.4% slower so speedo read 100 I'm doing 101.4
Whats the sizes of the tyres GSI?
i.e.
Stock 245/45/16 = Radius 313.5mm
New 255/35/18 = Radius 317.9mm
which is 1.4% slower so speedo read 100 I'm doing 101.4
#28
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