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Biggest aftermarket wheel sizes for a VF Commodore.

Forg

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I agree that tyre profile has nothing to do with the claim of tyre wear....So why a comment about compliance would come into the discussion is beyond me... :)
After the response to my comment, I'm pretty sure it was just a segue about how the lack of shock-absorption in the lower profile tyre increases wear on the rest of the car; it isn't intended to be his main point.

Hypothetically decreasing unsprung weight with larger wheels could reduce suspension wear but lets be honest here, nearly everyone who puts rubber bands on their wheels wants to slam the car on its arse, which definitely increases suspension and tyre wear!
Yeah, OK I can't disagree there. Mostly because they're doing it cheaply & badly. :)

My project car only has wheels 1" wider than the ones it came with (4cm wider tread but that's because of 70's "balloon tyres"), albeit 3" bigger in diameter, and it's about 2" lower than a standard 2dr & 4" lower than the standard 4dr which was sold with the same suspension except for spring/shock/rollbar ratings. I did everything through East Coast Suspensions, the suspension geometry is all fine, the only actual mod required was to adjust the Panhard rod to centre the rear diff, and the car definitely handles better than standard without any extra tyre wear.
Wear on suspension & body, yep, I'm with you. But all the camber, caster, etc that can be set have been; anything that'd cause extra tyre wear can be adjusted.
And it's the same with a VF, VE & VF have proper independent suspension & it's all adjustable if your lowered suspension requires changes.
 
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J_D 2.0

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You are trying to compare a car that was built in 1978, when 17 inch tyres were for exotic European cars and not even considered for the run of the mill taxi, to a car that was manufacturered in 1994 when it started to become the norm.....Sorry, but you are clutching at straws
Do you mean VB to VS Commodore? They can be compared directly because they have the exact same suspension system, just with different track widths, and didn’t change until they moved to the IRS setup in VS series 2 IIRC.

I‘m not clutching at any straws, I’m just saying it’s best to go with what the manufacturer designed and tuned the suspension of the car to use.

I know your probably going to bang on about them not saying anything about tyre wear but the article below says they do set up the suspension to suit specific tyre sizes and they normally tune for the most common size in that model, so the larger sizes are actually already a compromise.

https://www.caradvice.com.au/291176/low-profile-tyres-how-low-can-you-go/
 

vc commodore

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A lot of what you “win” or ”lose” by changing tyres depends a lot on the suspension geometry. Not toe and camber but caster angle (kingpin inclination) and scrub radius. The centre pivot point on the tyre is the ideal part of the tyre that can pivot directly on itself without scrubbing, everything outboard of this point has to scrub to be turned so the further away from the centre point the outside of the tyre is the more scrubbing needs to happen when the wheel is turned.

Another little problem with this comment is, how can the tyres only scrub the inner edge, when you turn the wheel and one pivots in and the other pivots out? They don't mysteriously only pivot in one direction when the steering wheel is turned
 

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I would love to hear your thoughts on my 1976 model valiant...OEM fitament was 185/75X14....These cars you'd get 30,000 to 40,000 out of a set of tyres....They are big heavy cars, with miles of suspension travel, up and down, side to side. Even when the cheese cutters are fitted to these cars, they have a bad habit of stuffing up idler arms within 12 to 24 months....

I fitted a set of 235/60X14 to this car...So a massive increase in tyre width....I managed to get 50,000 out of that set, before moving up to 245/60X14....Why did I get increased mileage out of them when you are making claims wider tyres reduce mileage?
I’m not the one creating blanket rules for every car since the model T Ford! The question at hand was the VF Commodore and like I said it’s best to use the sizes recommended by the manufacturer. Putting a rubber band on a 24 inch rim that’s 10 inches wide will increase tyre wear!
 

vc commodore

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Do you mean VB to VS Commodore? They can be compared directly because they have the exact same suspension system, just with different track widths, and didn’t change until they moved to the IRS setup in VS series 2 IIRC.

I‘m not clutching at any straws, I’m just saying it’s best to go with what the manufacturer designed and tuned the suspension of the car to use.

I know your probably going to bang on about them not saying anything about tyre wear but the article below says they do set up the suspension to suit specific tyre sizes and they normally tune for the most common size in that model, so the larger sizes are actually already a compromise.

https://www.caradvice.com.au/291176/low-profile-tyres-how-low-can-you-go/

You are claiming by going outside the manufacturers specified tyre sizing, it will increase wear....A VB Commodore suspension wasn't designed to take a 17" tyre, like the VP Commodore was when it was released, or even the VS....Yet it is fine to fit the 17" tyre to the VB and won't cause any problems. If that ain't clutching at straws I don't know what is
 

vc commodore

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I’m not the one creating blanket rules for every car since the model T Ford! The question at hand was the VF Commodore and like I said it’s best to use the sizes recommended by the manufacturer. Putting a rubber band on a 24 inch rim that’s 10 inches wide will increase tyre wear!

No it won't.....Suspension settings determine tyre wear issues, with this discussion.....

Blanket rules do cover the whole topic.......The topic being increasing tyre widths creating tyre wear issues and it is a myth
 

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Another little problem with this comment is, how can the tyres only scrub the inner edge, when you turn the wheel and one pivots in and the other pivots out? They don't mysteriously only pivot in one direction when the steering wheel is turned
I never said they only scrub the inner edge! Im saying a higher profile tyre will have more grip on the inner edge because of the extra flex in the tyre. The examples I’ve seen normally scrub the outer edges the worst as all the work is done by the outer edge of the tyres. That can probably be corrected with proper suspension mods/alignment to compensate but a lot of people just whack big arse rims on and don’t modify anything.

Having a proper suspension workshop deal with your car would be best as they will know what needs to be done. If your just going to go to Bob Jane etc they are just going to dial it to factory specifications and be done with it.
 

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You are claiming by going outside the manufacturers specified tyre sizing, it will increase wear....A VB Commodore suspension wasn't designed to take a 17" tyre, like the VP Commodore was when it was released, or even the VS....Yet it is fine to fit the 17" tyre to the VB and won't cause any problems. If that ain't clutching at straws I don't know what is
It’s not clutching at straws! The VB through VS Commodores had EXACTLY the same suspension setups. Pretty much all the parts are interchangeable FFS!
 

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It’s not clutching at straws! The VB through VS Commodores had EXACTLY the same suspension setups. Pretty much all the parts are interchangeable FFS!

Yes they are, but the VB wasn't designed to accept the 17" rims....The 17" rim didn't come into play until the VP, which was made 14 years later...So explain this comment you made...

"Like I said earlier the manufacturer/engineers design the car and tune the suspension to suit certain tyre sizes. Stepping massively outside these bounds is bound to have negative effects, which I myself am not willing to wear."

Or is it a case that jumping up 2 sizes with rim size 2 inches wider with rim width and 30 MM wider with the tyre is alright?
 
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vc commodore

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I never said they only scrub the inner edge! Im saying a higher profile tyre will have more grip on the inner edge because of the extra flex in the tyre. The examples I’ve seen normally scrub the outer edges the worst as all the work is done by the outer edge of the tyres. That can probably be corrected with proper suspension mods/alignment to compensate but a lot of people just whack big arse rims on and don’t modify anything.

Having a proper suspension workshop deal with your car would be best as they will know what needs to be done. If your just going to go to Bob Jane etc they are just going to dial it to factory specifications and be done with it.

My apologises it wasn't the inner edge...It was edges...But providing the tyres were wearing evenly, you can just swap out them for bigger ones, providing the rolling radius stays the same...The larger rims and tyres can't change alignment settings....Alignment settings are the things that dictate tyre edge wear....Reading that tyre edge wear is the key to setting the alignment up.....And that key is slowly being lost through the younger generation not giving a toss about learning from the older generation

And here is part of that key to reading a tyre...Scrubbing the outer edge on both says to me that the camber needs to be adjusted a little more negative, to transfer the weight away from the outer edge....
 
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