245/40/19's or 245/35/19's with 275/35/19's

[wide]

hi,

ive just got some 19" alloys & have bought some 275/35/19 tyres for the back & was wondering why the 370z & loads of bmw's all seem to run 245/40/19 fronts as oppose to 245/35/19. what are the pro's & the con's of running either.

thanks matt

[Stew]

Although a lot of people run 245/40 R19s on the front it should actually be a 35 profile.

 

I don't know why manufacturers have set up cars to run the 40 profile at the front but would imagine it's to keep the rolling radius the same (or near as dammit) between the front and rear axles.

[Aust350z]

What is the width of the alloy you just bought? You need to keep rolling diameter the same and thus the width of the rim will determine the profile of the tyre required.

[wide]

9j fronts 10j rears.

thanks matt.

[rich5259]

you want 245/35x19 on the front to keep the stagger in the rolling radius

[wide]

can anybody elaborate more plz?

[Wookiee22]

If you do a search for 'rolling radius' there are quite a few threads on the subject. Good luck!

[wide]

searched & still confused, plz more help needed.

thanks matt

[Stew]

What you want to know?

 

245/35 R19 and 275/35 R19 will be fine. You might want to go for something different if it takes your fancy!

 

 

The Zed is designed with a staggered wheel fitment 225/45 R18 and 245/45 R18. To keep the TC happy it's best to match the profiles. Most TC issues / cars skidding randomly etc are down to companies with no Zed knowledge recommending crap tyre sizes.

[wide]

will 245/40/19 work without t/c messing up? or is it defo worth going for 245/35/19's

thanks wide

[Stew]

will 245/40/19 work without t/c messing up? or is it defo worth going for 245/35/19's

thanks wide

 

It might well be great but then again you might end up in a hedge.

 

Some cars have been affected and others havent'

 

I'll take a stab that the 245/40 is cheaper than the 35 profile tyre? I would spend the extra few quid and do it properly.

[drmac]

hello to all.its my first post.i have a 2003 jdm fairlady and i am running 245/35-19 f and 275/35-19 rear.under full throttle acc the rear end tends to come out but that might be due to the yokohama advan sport i am running.it used to be better on the previous tyres which were goodyear f1 assymetric,so the 35 profile should not be an issue though the tyre choice might be.

[Chris`I]

hello to all.its my first post.i have a 2003 jdm fairlady and i am running 245/35-19 f and 275/35-19 rear.under full throttle acc the rear end tends to come out but that might be due to the yokohama advan sport i am running.it used to be better on the previous tyres which were goodyear f1 assymetric,so the 35 profile should not be an issue though the tyre choice might be.

 

How new are the tyres? When tyres are made they have release agent to help them pop out the mould, which can be very slippy. It can take upto 500 miles for this to wear off. That might be your issue. Sounds like you have the right profile tyres, so its likely to be release agent or tyre compound thats causing it. Do you have the same tyres (make and model) front and rear?

[drmac]

yes they are the same make i.e yokohama advan sport v103.the manufacture is '09.they have been driven around 800km.and u might be right about this mold thing but the eagles were more grippy though the vehicle 's ride had become very uncomfortable.its a bit better now.lets hope they start gripping more but at the same time i make sure that the tcs is active all the time as i dont want to land somewhere in the fields.