Good afternoon all. I changed my standard 17" RS alloys for 18" rs8 alloys a while back, and I was thinking yesterday. The 18s must be heavier, so therfore I'm loosing out on acceleration right? But I read somewhere that the turbo spools up quicker when it's pulling more weight, so would it balance itself out?

As well as the weight , you will probably have a larger rolling diameter which effectively raises the gearing of the car. That'll give you lower accelleration and theoretically a higher top speed if the engine has enough power.

As well as the weight , you will probably have a larger rolling diameter which effectively raises the gearing of the car. That'll give you lower accelleration and theoretically a higher top speed if the engine has enough power.

Unless you compensate with lower profile tyres.

So stick with 17s for performance. Is it true that the turbo spools up quicker when pulling more weight then?

So stick with 17s for performance. Is it true that the turbo spools up quicker when pulling more weight then?

Can't answer that one.

If the wheels are made by OZ, or another top notch manufacturer, then they may actually be lighter then your oem ones.

If they are replica wheels, then you will notice a drop in acceleration, and cornering ability. I popped 18" A8 reps on my Fabia, and although it looked fab, it drove like a turd.

HTH

I've been thinking of getting some new wheels so I'll look for some lightweight wheels, or maybe even go back to 17s?

Well i'm sure my wheels will be heavier and possibly larger in diameter but i can't say i've noticed any dramatic loss of acceleration so even if it has affected it can only be by 10ths of a second so i wouldn't worry about it unless you live your life a quarter mile at a time:rofl:

and if you don't track race your car then i don't think you would notice any adverse effect on your handling either as mine still goes round corners fine:thumbup:

To be honest I never noticed any changes in handling, in anything it could've even improved.

there could be a problem elsewhere and if your not sure then it may be worthwhile having it checked on vagcom if you can get access to it but if no faults are present then it may be that your just getting used to the power and thats why it feels tame,having said that mine has good days and bad days,i just prefer the good days

As well as the weight and rolling diameter issues, I'm sure I've seen the effects of inertia mentioned with bigger wheels.

I'm not going to attempt a technical explanation - but maybe we have some mechanical engineers that can go into more detail.

Something to do with the weight distribution being at a greater radius increasing the moment of inertia?

As mentioned by others, I can't see it making more than a tenth or two difference though.

To be honest I've found that my Octy puts the power down much better with bigger wheels, especially if its been remapped. Cuts out a lot of wheel spin.