How much performance do heavy wheels give up?

[davey_83]

Found this very interesting 🤔 

 

 

 

[G1en]

Yeah, it basically confirms what my thoughts were. The wheel weight makes a small difference but nowhere near the 4 times or 5 times unsprung weight multiplier banded about. 
he doesn't and no one seems to factor in that a lightweight wheel is 9kg say against a 12kg cast wheel but you also have 9kg of brake disc and 10kg of tyre plus rest of calipers and hubs so as a % overall weight reduction its negligible.

basically lighter is better but not worth getting hung up about a few pounds/kilos as any non professional driver will not notice or care, buy the wheels you like.

[davey_83]

Oh nice one fella. Towards the end he referenced moving to an 18' from a 19' for example would yield more performance than same size lighter wheels. Very interesting I thought.

[Ekona]

Anyone who has ever driven a 350 with the touring wheels and then swapped to Rays will tell you it’s a night and day difference. Even a few kilos shaved there makes the whole car feel so much more nimble. It’s why I stayed with 18” on the 645 rather than move to 19”s. Once you’ve tried it you realise what a revelation lighter wheels can be: far more noticeable than an extra 20bhp here or there. 

[G1en]

I have noticed an improvement in acceleration/gearing going from a 40 profile to a 35 profile rear tyre this year. essentially like dropping a cog on a pushbike so its easier for the drivetrain to turn, thats prob why he says going from a 19-18 inch wheel reaps more benefit than a 10 to 9kg wheel swap. you can improve the gearing by either a final drive swap, smaller wheels or lower profile tyres, it all does the same thing in essense. I am no expert but I think thats what he is getting at without going into the detail of confusing the viewer. Its also probably why lots of sprint/hillclimb cars (that i have seen) fit the smallest but widest wheels they can get away with to clear the brakes/arches. No doubt a lighter wheel is better and we should always opt for that if competing (and strength taken in to consideration) but your not going to be adding 50kg of multiplied weight to the car and adding 5 seconds to your laptime by going a kilo per wheel heavier like the internet would have you believe.

[andy james]

I Love the look of my 19” show wheels which suit the mods I’ve done now she is purely a road car.

Having said that the 18” Rays fitted to my car new always made the car feel more nimble on the road. Once fitted with competition tyres for hill climbing and sprinting the difference was even more noticeable.