I have been researching the forum for posts regarding replacement tire sizes to fit a Touring 6MT. After reading all the information available I have arrived at a stagger combination that I have not been mentioned. 255/40-18 front and 275/40-18 rear. This combination essentially matches the stock 225/45-18 front and 245/45-18 rear numbers for diameter, circumference, revolutions per mile and stagger while at the same time putting 30mm more rubber on the road. As a result the speedo, ABS and VDC should not be affected. I realize the 275's may be just a bit wide for the stock 8 inch rims, but what else is wrong with this package?

 

Should be OK with 8.5" front and 9.5" or 10" back, but 255/40s are hard to find. You could also put 285/40s in back, but again another hard size to find. 275s on 8" rims not a good idea, you'd have severe tire buldge, which could break loose. Most tire shops would not do it, due to the liability. Why not stay with the standard recommended 245/40s front and 275/40s rear on the correct width rims. I did that with Nismos, (Dunlop SP9000s) and I'm very pleased.

Lou

 

Just put spacers on the back rears to get the staggered setup.

 

Continental Contiextreme makes those size 255/40/18 and 275/40/18. You can get them at Tire Rack. 255/40/18 are $165 and 275/40/18 are $168. These are ultra high performance all-season tires.

 

Thanks. These sizes are also available from several manufacturers. More research tells me that i would have to also buy 4 new rims because the stock 8 inch rims are too narrow for this setup. It is interesting that the stock Bridgestone RE040 tires do not comply with Nissan's stated requirement for a .3 to .75 stagger. The stock 225/45-18 front has a 25.9 inch diameter and the 245/45-18 rear has a 26,7 inche diameter for a .8 inch stagger. I also find that the diameter for the same size tire differs slightly from manufacturer to manufacturer. I would like a little more rubber up front to help with understeer. The closest I have come for replacement tires on stock 8 inch rims are the Goodyear F1 with a 245/40-18 front (25.7 inch diameter) and 245/45-18 rear (26.6 inch diameter) for a stagger of .9 inch. Is there a problem using 40 and 45 series tires together?

 

CORRECTION, the Nissan required stagger is .5 inch to .75 inch

 

Kbom we are not talking about a lateral stagger. we are talking about the stagger of overall diameter between wheels. Changing this makes the VDC think the wheels are rotating at different speeds than they are.

BAd news when it uses this relationship to determine application of countermeasures!

 

Everyone says that the ideal front/rear setup should be 245/40 f and 275/40 rear, but if you do the math, 255/40 in front is the CLOSEST to stock you can get. This setup results in a 0.6 stagger, falling right into the .5 - .75 stagger requirement by nissan. i am running bridgestone s03's in this size (SUPER GRIPPY) and have noticed NO slip light, plus a little less understeer. 255's up front are perfect for me, and fill up the wheel well a bit better.

 

You got it. I've been recommending this to people for a long time. My next set of tires will definitely be a 255/275 combo. My current 245/275 combo understeers pretty badly, so the extra 10mm in the front can only help. And I'm also hoping the 255 will fill the front wheel well a bit better, like you said. I find a 245/40/18 to be a bit small for that huge wheel well. (Need some 275's in there!)

 

Sport Compact Car magazine put 275s on the front and rear of their project Z and along with a new diff and a hotchkis sway bar pulled 1g on the skid pad.

 

Yup. That was one of the many articles that lead me to the wider-is-better approach in the front. In their latest mag, they added Nismo suspension to it. Now they say it actually has oversteer, and is getting a bit scary. They figure they'll drop the rear Hotchkis sway back down to the soft setting (instead of medium) and that should take care of it and bring things back to neutral.

 

If you read the the early reviews done by raceboy and others, you'll find that they noted the s-tune suspension made the car more neutral along with the recommended stagger.

So that fact that the car oversteers more with a non-stagger set-up is logical.

I think that's the reason Nismo suggested the wider wheels and 245/275 set-up with s-tune in the first place.

This is why I bought it.

 

I believe Raceboy's review actually stated he was using a 245/255 tire combo, which is less stagger than recommended. I'll most likely have a 20mm difference, though, so I'm sure it would be fine. I'm leaning more and more towards the Nismo suspension after my research lately. Either that or the RS-R Ti2000 springs with stock or Koni shocks. (Depending on if the Konis actually benefit sufficient to merit the cost.) I love the idea of the Nismo setup's matched springs and shocks, though. Very important to me.