"18s suck for ride quality and/or handling. 19s are worse than 18s.

John Mueller "



This has been going around on the DSM group emails. John is the suspension expert at Road Race engineering that does incredible **** with the uncomfortable JIC FLT's and some how makes them corner 10X's better with a softer spring rate.

Those that know know what i'm talking about.

I thought id post this to stir up some conversation amongst you all, particularly those that don't think 18's would hurt performance.

I neither endorse, nor reject this view, although i will say that given John's expertise, and the results i have seen with the JIC's hes tuned for me, i would err on the side of listening to his opinion.

But...as always, argue away.

 

I wouldn't doubt it considering the car was built around 17" wheels.

I'd think the only true way to truly prove it would be with some professionals and comparing lap times.

 

i think the HKS EVO added 18's and the g went to like .98 from the stock 17's at like .95 something like that, if anyone else knows the exacts....

 

Right. But that doesn't mean anything at the point where the 18's weren't the ONLY thing that HKS added.

The coilovers they added may have provided handling improvement to offset the loss of performance from 18's, but that doesn't mean that the same coilover setup with 17's wouldn't have been better

 

So Alex,
Since you have the RRE setup, what is the street ride comfort like? Is it much harder than stock? I'm thinking about this setup but I don't want a killer stiff street ride. I stayed with 17" wheels to keep down the weight as well as for handling. Thanks in advance.

 

I think the best question to ask is what TIRES did HKS use.

 

The ride is not THAT much harsher, but it is noticeable. But let me tell you, i use this car as a daily driver and i never regret getting the coils. It corners insanely.

 

Whats his reason for saying this? There are pros and cons, but what are they in his opinion? Without reason it just sounds like one persons view

 

And thats exactly right. it IS one person's view. But i put an incredible amount of trust in this one person's view given his racing pedigree.

But as far as specific reasons, i have yet to really ask. His opinion is primarily formed from experience, road race is always testing out different setups on the track.

 

Most people that buy 18's buy them because they look better.

Thanks for the info though.

 

I've read in several places that 18" wheels/tires offer the optimal combination of grip, ride, sidewall flex, and heat management. If I am not mistaken, all of the WRC teams use 18" wheels in tarmac events, most DTM and FIA touring cars use 18" wheels, and ALMS prototypes use (like the Audi R8) use 18" wheels. The only reason F1 does not is because of regulations. I will check today to find the references...

 

The McLaren F1 uses 17" wheels. Good enough reason for me.

 

Exactly what I was thinking.

 

Can you please post pics of your car? I am thinking about getting the Jic from RRE.

 

I always thought that if you want the best combination of ride and handling the 17" rim lets you get away with a little more sidewall with out affecting your overall gear ratio as witha 18 tire. I think the best combo will be a 245-40-17 on the stock wheels or A lighter 17x8 rim with a good coilover system tuned correctly and a rear tower brace and a larger rear adjustable sway bar.

just my 2 cts