Custom wheels give all 4 tyres the same width.... changes grip and balance

  • Thread starter Vagabond
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Unbelievable really that this happened and great job to find this!

So, is this true only for custom rims or also, if you use other than stock tyre compounds? That would explain why these MR's seem to change behaviour completely when you fit softer/grippier tyres.
 
Great find, obviously and error.
This was the reason I refused to change wheels on many MR/RR cars in GT5, even though that was for aestetical reasons only.
Hopefully this will get patched soon.
 
Thanks for posting this, interesting reading and probably go un-noticed by the majority. Not a fan of swapping rims anyway but have done on a couple of cars - explains why they are now just parked up in my garage.

Cheers Bee9
 
PD would not reduce the width of the rear tire.
We've tested this extensively and found that the rear tyre behaves as its appearance suggests ie if you fit custom rims to a car that usually has wider rears, the width is reduced to the same as the fronts with a corresponding loss of grip and traction. Fact.

Look, anyone can test this if they are sceptical - pick a car that has really fat rears, drive it as fast as you can for a few laps, then change the rims to any size you want (diameter doesn't matter) and try and drive it the same way without changing anything else in the setup.
Unbelievable really that this happened and great job to find this!

So, is this true only for custom rims or also, if you use other than stock tyre compounds? That would explain why these MR's seem to change behaviour completely when you fit softer/grippier tyres.
This particular issue only exists in changing rims - any other balance issues that occur when changing tyre type are an issue with grip changing car characteristics, not changing tyre width front relative to rear. On the whole, with few exceptions, the stock cars have the best balance on the tyres they are fitted with as standard.
 
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Now confirmed on several cars and by multiple sources, we have discovered that fitting custom wheels gives your 4 wheels/tyres of the same width. So in the case of cars that have wider rear tyres on stock rims, you lose rear grip and the whole balance of the car is ruined.

Great find, thanks for everyones time 👍
 
So this is the bloody problem. I was fuming mad when I realised my tune for the E46 M3 was so ****. I was so pissed off at myself for ruining a car that was meant to be my dream 'ring toy, but rendered it undriveable after my upgrades, including the rims. Got so mad I sold the car in game as it was really pissing me off. GAH.
 
Wow, this is nuts. It should be fixed ASAP. I hate stock wheels on most of the cars and the first mod I always do - change the wheels to aftermarket. But I still want my GRIP!!
I really didn't have any major issues with GT6 that most of the people did, but this thing... It should be fixed now.
 
If this is true, it explains why the TC Challenger I bought was undrivable as I did change the wheels.
 
Yeah, realised that after I posted...spur of the moment :embarrassed: :lol:

Can't think of any cars that understeer that badly that you'd want to ruin the rear grip in this way. There are other tuning methods that would reduce rear grip in a more controlled manner if this was the only solution.
 
Ok then, just figured there may have been some higher end AWD's where you may have had to rely on higher downforce on the front for the corners which obviously reduced straightline speed, whereas putting the bigger rims on to loosen the back could have meant less downforce on the front and better straightline speed.
 
VERY IMPORTANT FIND!!!
This explains a lot!
I started the trhead about the f40 being close to undrivable and I have had custom rins on it from the beginning!!!
So just to see if this patch did anything to the f40 I just tried it on brands hatch, where the faulty handling really shows its stuff, and first of I tried with my "fixed" settings with different tires back and front and if anything would have been changed this would now be undrivable with lots of understeer, and it was! Drive it yesterday without any problems like thus so thinking its been fixed I put sport mediums on all around... Totalt spinnfest! Can hardly take a corner! So nothing fixed then.
Now I went and put on the standard rims!
Tried again.... And what do you know! The car handles slightly better!!!
Its gone from total catastrophe to bad but can be driven, even though the backend still bites its got more grip!
Very interesting!!!
This means no more custom rims!
And that is very boring! :)
 
Now I went and put on the standard rims!
Tried again.... And what do you know! The car handles slightly better!!!
Its gone from total catastrophe to bad but can be driven, even though the backend still bites its got more grip!
Very interesting!!!
This means no more custom rims!
And that is very boring! :)

The F40 should be difficult to drive at the limit, so this sounds fine :)

And you can't see the rims when you're driving the car... save the rims for Photomode ;)
 
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Absolutely ridiculous! I was struggling with the RUF BTR and the Stratos, just changed back to stock wheels and there's a noticeable difference.

I'm hoping this is an accidental hint at a currently locked feature; wheel width adjustment
 
Yes exactly, it proves that the tyre width physics are there. So although this is a shocking glitch it's making me optimistic about future updates
Just have to get their attention on this fact so that custom rims copy the tire widths of each tire when changing from stock. This will have to be checked per car basis as I do not think that all the rims come is depths as some of these fat rubber rears like on the F40, GT40 and other cars which easily can sport deep dish rims. Perhaps some algorithm additions to change the rim structure to suit the tire width would help since it can be drawn on the fly. Hope that they can do this sufficiently and quickly as I need my black on machined lip rims...just too sweet on some cars.
 
I could see this being a more involved fix, as quite a few of the wheels featured have differing shapes in different widths, Enkei RPF1 and Volk TE37's come to mind
 
nice find Vagabond, perhaps we will get an update in future to allow for wider rims. Seeing as the width makes a difference which looks like potential extra's to come our way.
 
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