Jump to content
SAU Community

Recommended Posts

Hi guys,

Quick question, I'm goin to get some Yokohama Advan v103's fitted this weekend, and am currently running 17 x 9 te37's, jsut wondering what would be the best width to go for 245 or 255, and what differences the extra 10 mil will make in handling / ride quality.

Any help will be appreciated.

Cheers,

Dave.

Link to comment
https://www.sau.com.au/forums/topic/160395-tyre-width-question/
Share on other sites

With 245/40R17, your speedo will read 0.65% faster. 627.8mm rolling diameter

With 255/40R17, your speedo will read 0.62% faster. 635.8mm rolling diameter

Stock 205/55R16 is 631.9mm rolling diameter. Bees dick in it

Different rolling diameters cause speedos to be out by a percentage not a static amount

You've got the wider rim, may aswell use it and get the wider rubber if they're the same price. If it was me, I'd get which ever is cheaper though :happy:

Edited by salad
With 245/40R17, your speedo will read 0.65% faster. 627.8mm rolling diameter

With 255/40R17, your speedo will read 0.62% faster. 635.8mm rolling diameter

Stock 205/55R16 is 631.9mm rolling diameter. Bees dick in it

Different rolling diameters cause speedos to be out by a percentage not a static amount

You've got the wider rim, may aswell use it and get the wider rubber if they're the same price. If it was me, I'd get which ever is cheaper though :happy:

i think standard GTR tyre size is 225.

personally I think on a 9inch rim on a GTR go the 245. but there is not much in it. and some brands 245 will have as much tread with as another brands 255. if there is much of a price difference just get the 245. if there is not much difference get the 255.

i think standard GTR tyre size is 225.

personally I think on a 9inch rim on a GTR go the 245. but there is not much in it. and some brands 245 will have as much tread with as another brands 255. if there is much of a price difference just get the 245. if there is not much difference get the 255.

Oh whoops didn't realise that he had a GTR. Anyway, 225/50R16 is 0.5mm smaller than 205/55R16, or 0.08% so all calculations hold

Lucky me :D

Edited by salad

thanks for hte replies guys, but i guess what im trying to ask is what kind of influence on ride / handling will different sized rubber stretched over the rim produce?

for example will wider tyres cause the car to tramline more, or will they provide more grip? what are the advantages/disadvantages of going the wider or the narrower tyre on the rim?

Cheers,

Dave

Get 255's.....they are perfect for a 9" rim. If you use 245's the rim protector bead around the tyre does not stick out past the rim like it's suppose to.

The price difference between the two is minimal because 255's are commonly used now. I went 265 last time and the price jump was HUGE because 265 is not a common size. I will go back to 255 next time because there is buggerall difference for a road car and I can't justify the large price hike for 265's

mmmm, i see most of you guys running 40 profiles. I have 17x9's with 45 profiles all round as i thought this was the norm?

I have power fc and my speedo doesn't seem to be out too much? i do run 235's if that makes a difference and its a gtst!

Edited by mr_rbman

The profile or aspect ratio is a ratio of the tyre width. So a skinnier tyre with a higher aspect ratio can have a similar diameter to a wider tyre with smaller aspect ratio.

Eg. 205/55R16 is almost identical to 225/50R16 in rolling diameter.

225/45R17 is almost identical to 255/40R17

etc

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I neglected to respond to this previously. Get it up to 100 psi, and then you'll be OK.
    • I agree with everything else, except (and I'm rethinking this as it wasn't setup how my brain first though) if the sensor is at the end of a hose which is how it has been recommended to isolate it from vibrations, then if that line had a small hole in, I could foresee potentially (not a fluid dynamic specialist) the ability for it to see a lower pressure at the sensor. But thinking through, said sensor was in the actual block, HOWEVER it was also the sensor itself that broke, so oil pressure may not have been fully reaching the sensor still. So I'm still in my same theory.   However, I 100% would be saying COOL THE OIL DOWN if it's at 125c. That would be an epic concern of mine.   Im now thinking as you did Brad that the knock detection is likely due to the bearings giving a bit more noise as pressure dropped away. Kinkstah, drop your oil, and get a sample of it (as you're draining it) and send it off for analysis.
    • I myself AM TOTALLY UNPREPARED TO BELIEVE that the load is higher on the track than on the dyno. If it is not happening on the dyno, I cannot see it happening on the track. The difference you are seeing is because it is hot on the track, and I am pretty sure your tuner is not belting the crap out of it on teh dyno when it starts to get hot. The only way that being hot on the track can lead to real ping, that I can think of, is if you are getting more oil (from mist in the inlet tract, or going up past the oil control rings) reducing the effective octane rating of the fuel and causing ping that way. Yeah, nah. Look at this graph which I will helpfully show you zoomed back in. As an engineer, I look at the difference in viscocity at (in your case, 125°C) and say "they're all the same number". Even though those lines are not completely collapsed down onto each other, the oil grades you are talking about (40, 50 and 60) are teh top three lines (150, 220 and 320) and as far as I am concerned, there is not enough difference between them at that temperature to be meaningful. The viscosity of 60 at 125°C is teh same as 40 at 100°C. You should not operate it under high load at high temperature. That is purely because the only way they can achieve their emissions numbers is with thin-arse oil in it, so they have to tell you to put thin oil in it for the street. They know that no-one can drive the car & engine hard enough on the street to reach the operating regime that demands the actual correct oil that the engine needs on the track. And so they tell you to put that oil in for the track. Find a way to get more air into it, or, more likely, out of it. Or add a water spray for when it's hot. Or something.   As to the leak --- a small leak that cannot cause near catastrophic volume loss in a few seconds cannot cause a low pressure condition in the engine. If the leak is large enough to drop oil pressure, then you will only get one or two shots at it before the sump is drained.
    • So..... it's going to be a heater hose or other coolant hose at the rear of the head/plenum. Or it's going to be one of the welch plugs on the back of the motor, which is a motor out thing to fix.
    • The oil pressure sensor for logging, does it happen to be the one that was slowly breaking out of the oil block? If it is,I would be ignoring your logs. You had a leak at the sensor which would mean it can't read accurately. It's a small hole at the sensor, and you had a small hole just before it, meaning you could have lost significant pressure reading.   As for brakes, if it's just fluid getting old, you won't necessarily end up with air sitting in the line. Bleed a shit tonne of fluid through so you effectively replace it and go again. Oh and, pay close attention to the pressure gauge while on track!
×
×
  • Create New...