VE SS Tyre fitment advice pls 245's or 255's best pairing with 265 rears

[Kev38]

Firstly - thanks for the reply's thus far

Secondly - I've read and re-read all your reply's along with the provided links to other threads & info.

Thirdly - I now need a Bex, a cup of tea and a little long lie down

Lastly - perhaps I should rephrase the original question :

Does anyone forsee any problems with this proposed staggered set up on a '07 VE SS Sedan:

265/35R20 tyres fitted to 20 x 10 +42 rears with 245/35R20 tyres fitted to 20 x 8.5 inch +45 fronts ?

 

[mechanic]

Have a check up on the offsets used with HSV's...Those cars use exactly the same bearings as the base model car.

Factory fitament tyres with those are 245/35X20 on the front and 275/30X20 on the rear...

I think we are agreeing on the topic.
Just don't fall into the trap thinking that all 10 inch wheels are the same offset. You can buy them to suit many different setups.
If old mate doesn't know this he might just buy any 10 inch wheels off ebay.

Must be plenty of Commodores out there waiting to have wheel bearings fail and the scrub radius changing considerably, which will lead to sideways steering

Is this sarcasm?

 

[Kev38]

If old mate doesn't know this he might just buy any 10 inch wheels off ebay.

If old mate doesn't know this he might just buy any 10 inch wheels off ebay.

'Old Mate' already has the wheels and no they weren't bought off eBay. They are brand new still in their box's and have been sitting in my garage for a few years waiting til the tyres on my current 20x8 square set up needed replacing.

Which happens to be now.

Hence me seeking advice/opinions on fitting the best tyre size pairing to the 265's intended to be fitted to the rears (which, from my undenied limited understanding, is the best size tyre on a 20 x 10 rim with a +42 offset that I could fit to avoid having to have the rear guards rolled - which I really don't want to do).

I'm fully aware of the HSV setup and offsets - 36P and 57P - bloody fantastic.

They aren't what I have.

As I said, I already have the wheels and I have to work with the offsets they have. So, now I need to fit tyres on them and avoid any guard work body modifications.

Surely there's someone around that has done something similar in the past ?

I'm just trying to work out if 245's or 255's would be the better pairing with the 265 rears....

 

[vc commodore]

255/35X20 will be a slightly large OD when paired with 265/35X20, which may cause issues with your electronics.....I suspect the 245/35X20 will be closer to 265/35X20......

 

[vc commodore]

I think we are agreeing on the topic.
Just don't fall into the trap thinking that all 10 inch wheels are the same offset. You can buy them to suit many different setups.
If old mate doesn't know this he might just buy any 10 inch wheels off ebay.


Is this sarcasm?

I am quite aware there are different offsets with all wheels, hence why I posted up some other links within this forum over wheel offsets relating to VE commodores.

Wheel offset has no bearing on premature wheel bearing failure.....It does effect turning circle, but not premature wheel bearing failure...

Newer model cars actually have more load on wheel bearings, when compared to earlier model cars...Reason being is, the offset of modern cars is more towards the inside of the car, where older cars had the offsets more to the outer of the car....So changing the offsets on later model cars would probably reduce the load on the wheel bearings, unless the rim weight is increased, which does occur with some aftermarket rims

Oh and just in case you aren't aware, I get paid to play with wheels and tyres all day....

 

[losh1971]

255/35X20 will be a slightly large OD when paired with 265/35X20, which may cause issues with your electronics.....I suspect the 245/35X20 will be closer to 265/35X20......

Wouldn't the 255/35 be closer to OD of the 265, than a 245?

 

[vc commodore]

Wouldn't the 255/35 be closer to OD of the 265, than a 245?

Possibly...Didn't bother using the online calculator....Just going by OE HSV fitament...Fronts being a 245/35 and the rears being a 275/30...I suspect a 265/35 would be about the same OD as the 275/30

 

[Kev38]

255/35X20 will be a slightly large OD when paired with 265/35X20, which may cause issues with your electronics.....I suspect the 245/35X20 will be closer to 265/35X20......

Thanks VC. Your thinking that the 245 would be a better match is what I had been thinking too.

But here's where I'm a bit confused and why I came here seeking advice.

Putting both the 245 & 255 separately up against a 265 into an online Tyre Sizing calculator (actually acouple of them) gives the following results:

255/35R20 Overall Diameter = 686.5 mm 265/35R20 Overall Diameter = 693.50 mm

- a Diameter Variance of 7mm (1.02%) between them

whereas:

245/35R20 Overall Diameter = 679.5 mm 265/35R20 Overall Diameter = 693.50 mm

- a Diameter Variance of 14mm (2.06%%) between them

This wheel and tyre stuff is well beyond my knowledgeand understanding base so I'm talking blindly out of my ar$se I know, but on paper it appears to my uneducated self that the 255 is actually a closer match to the 265 even though my brain is telling me that a 245 is likely the better match.

Again, hence why I'm here seeking advice .

If you're lucky enough to be paid to play with wheels and tyres VC, can you ( or anyone else for that matter - don't be shy) help me out and maybe tell me what I'm missing in the equation or maybe whatever else I'm not considering etc

thanks heaps !

 

[losh1971]

35 is % of the width.

 

[vc commodore]

Honestly if it were me, I'd be going the 245/35 for 2 reasons....Easier to obtain, and cheaper and 2ndly it is a factory fitament....