Fao: Tyre Gurus

[gkzlah]

Just a question for the tyre gurus out there.

Currently in the market for new tyres, and after lots of research (which includes here & g35driver)

Bear in mind i'm on a budget at the moment, and have narrowed it down to the following.

Nankang NS2 (I figure brand new chinese tyres are better than getting secondhand anything)

Setup for these will be 245/35/19 Fronts & 275/35/19 Rears. (Quoted $910 fitted by TTF in dandenong)

Federal 595s

245/35/19 Front & 275/30/19 Rears. (Quoted $860 fitted by wheeltech)

Now here's the question - Are there any issues running a 30 series tyre for my rears as opposed to a 35 series?

Would it actually look stupid considering theres a 5mm difference fronts vs rears?

I've also read that if i dont have correct tyre sizes that this may prematuresly set off the VDC, so would running the 35series front and 30 series rear cause this in the tyre size im looking for?

If it helps i'm currently on 235/45/17 all round

Thoughts? (or any recommendations for tyres accepted lol)

[sonicii]

2 points. first. the difference in tyre sidewall height between a 275/30 and a 275/35 is just under 14mm (82.5mm vs 96.25mm)

second, the difference will affect your speedo accuracy. The 275/30R19s will be the closest diameter to your original tyres, so will impact the least on your speedo.

Not sure how different you can go before the VDC gets too upset.. the V35 coupe 18s are different tyre size front/rear, so I guess they don't need to be exactly the same diameter.

[gkzlah]

2 points. first. the difference in tyre sidewall height between a 275/30 and a 275/35 is just under 14mm (82.5mm vs 96.25mm)

second, the difference will affect your speedo accuracy. The 275/30R19s will be the closest diameter to your original tyres, so will impact the least on your speedo.

Not sure how different you can go before the VDC gets too upset.. the V35 coupe 18s are different tyre size front/rear, so I guess they don't need to be exactly the same diameter.

Thanks for that, what you're saying is making a bit more sense now when I'm using the tire calculator...

That being said as the 275/30s are closest to the original tires, would it be best to be running a 235/35/19 on my front compared to the 245/35?

having put those numbers in the the diff between the 245/35 & 235/35 is just 3.566mm (85.598mm vs 82.042mm)

It shows the 235/35s will impact the speedo less, and are as close to being the right setup for the tyres? (or did I just answer my question?)

[sonicii]

the Speedo sensor is in the transmission, so the size of the driven wheels only will impact your Speedo, in a RWD car, this is just the rear wheels. The front wheel size won't affect the Speedo, but may impact the VDC if they are too different to the rears.

hope this makes sense.

[gkzlah]

makes plenty sense. thanks for the help!

[mosoto]

Now here's the question - Are there any issues running a 30 series tyre for my rears as opposed to a 35 series?

Would it actually look stupid considering theres a 5mm difference fronts vs rears?

there's actually only a 3.3mm difference overall diameter between a 245/35 & 275/30. I don't think you'll even see it.

secondly it's as close as you're going to get to identical rolling diameters and it won't upset VDC at all as it's under tolerance

Here's your reference material http://www.miata.net/garage/tirecalc.html

[scotty nm35]

the Speedo sensor is in the transmission, so the size of the driven wheels only will impact your Speedo, in a RWD car, this is just the rear wheels. The front wheel size won't affect the Speedo, but may impact the VDC if they are too different to the rears.

hope this makes sense.

M35 uses the wheel sensors as the speed trigger for the speedo, not the gearbox output shaft sensor. I doubt the V35 is any different. I bet if you changed diff ratios the speedo would remain accurate, but raising the tyre size will still change it obviously.

[sonicii]

there's actually only a 3.3mm difference overall diameter between a 245/35 & 275/30. I don't think you'll even see it.

secondly it's as close as you're going to get to identical rolling diameters and it won't upset VDC at all as it's under tolerance

Here's your reference material http://www.miata.net...e/tirecalc.html

?? Even using the calculator you shared, it gives a diameter difference of 1.1in, which is about 27mm.

[sonicii]

M35 uses the wheel sensors as the speed trigger for the speedo, not the gearbox output shaft sensor. I doubt the V35 is any different. I bet if you changed diff ratios the speedo would remain accurate, but raising the tyre size will still change it obviously.

thanks. The FSM isn't too clear on this. (or I'm not looking in the right place.)

[thinktea]

I just had my tyres changed and as part of the process, I considered getting them from tire-rack.com in the US.

I was targetting the Hankook Ventus V12 and was quoted $1,700 locally and $1,100 from the US (inclusive of delivery and taxes), so the difference is substantial if you are on a budget. Of course, a certain amout of patience is required for the delivery if you go the overseas route.

While I did consider the Nangkang S2 and the Federals 595s, I ended up getting a slightly lower spec Hankook (s1 Evos) locally from Donnellans near Box Hill for $1,500 fitted, balanced and aligned. Very happy with them so far.

Btw, they were 225/40/19s for the fronts and 245/40/19s for the rears (which is stock for the OEM 19s, but very hard to get in a matching pair locally).

[gkzlah]

thanks for all the responses guys, also did a quick check on g35driver to make sure the VDC won't have a brain fart when I put them on.

I think i'll be going with the federals (for this instance anyway)

Most reviews / reports i've read on them shows that they are a pretty decent tyre, and considering the budget i'm on I think it's a decent bet.

The car is mainly a daily driver, and I don't really intend on taking it to the track.

Just would like a bit more peace of mind when its wet.

Maybe we can start a thread (sticky perhaps) with everyones setups (offsets / tyre sizes) centralised to the v35 forum to make things a little bit easier for others, (on top of using g35driver)

will post pics when I get the wheels on..

[mosoto]

?? Even using the calculator you shared, it gives a diameter difference of 1.1in, which is about 27mm.

Try it again, but use the right figures this time LOL. remembering here that the OP was comparing the tyre wall sizes front to rear.

A 245/35/19 has a sidewall of 85.8mm

A 275.30/19 has a sidewall of 82.5mm

thats a difference of 3.3mm in the sidewall or 6.6mm in diameter.

Edited December 6, 2011 by mosoto

[sonicii]

Sorry, my mistake.. I wasn't comparing the fronts to rears, I was comparing the OP's rear tyre size option.

He mentioned he will be using a 245/35R19 on the fronts, but was tosing up between a 275/30 or a 275/35 on the rear, between which there is a 27mm diameter difference.