Would 23 lb wheels (Miro) offset the advantages of upgrading to grippier tires?
 

I'm currently driving stock wheels/tires and I keep hearing that upgrading to grippier tires such as Pilot Super Sports will transform the car into a handling dream. I'm about to purchase a set of Miro 398's 18x8.5 (TE37 reps) with 225(or 235)/40/18 PSS tires all around (square).

For street driving will the handling characteristics between the Miros and a wheel such as the RPF1 be very noticeable? I don't want to cancel out the handling advantages by equipping wheels that are too heavy. Also, would you guys recommend 225/40/18 over 235/40/18? Thanks!

Im going to guess your acceleration will be effected, noticably. Where as lateral grip may be improved. Either way I like the RPF1>TE37 style.

I wouldn't worry much about a few pounds extra for wheels unless you're being paid for your lap times...

It's a personal thing, but increasing or reducing unsprung weight will not only impact acceleration times, but how your suspension reacts (ie there's less or more weight for the suspension to try and keep in contact with the road). I run significantly lighter wheels (Desmond Regamasters) on my car, and I find the difference in ride and handling more noticeable than any difference in acceleration.

A change in unsprung weight does not "offset" an increase in grip; at least not directly.

If it did have a measurable effect, you would have bigger issues to deal with, a severely underdamped system, to be precise.

I run those wheels: Miro 398's 18 x 8.5 with 245/35/18 pilot super sports. That tire size keeps the gearing the same as stock 215/45/17. Grip is improved to the point where I can't psychologically drive fast enough on back roads to find the limit (I don't feel safe/within my skill level driving that fast basically). According to the quarter mile I'm about even maybe a little slower not sure yet and I haven't ran it enough times in the cold weather.

However, on the street its not noticeable really. I have the standard bolts-ons and e85 ecutek tune. The weight difference is only 3-4 lbs anyways.

Edit: Miro's 22 lbs My PSS tires: 22 lbs
stock wheels 20 lb , stock tires 20 lbs.

Hmm the difference in acceleration, if any, is not noticeable to you during street driving? My motor is stock so I'm not sure if the same would apply to me. What would be the advantage to retaining the stock gear ratios? Gas mileage? Also, what kind of drop did you do?

Ok, I'm going to speak with experience since overall my rim + tyre package I'm running is slightly heavier than stock.

I'm running Advan RG-D 18x8.5 and they're 17.6lbs which are much lighter than the 23lbs you mentioned. Add tyres to the rims and you have something heavier than stock. It's never just the weight of the rim but how big (17 or 18) and wide rim you're going. It's also the weight of the tyre added to it and if you're running wider, you need wider tyres and that's more weight.

With my RG-Ds and Kumho KU39s(235/40/18) and stock motor, I feel a difference in a lot of things. It takes more gas to get it moving, it takes longer to stop and it doesn't feel as direct in terms of steering compared to when I was stock. I've gone back and forth between the RG-Ds and stock rims enough times to give you my 2c on this.

For our cars, I advise against heavy rims period. If you only care about aesthetics and don't care about how it drives then by all means do whatever. But if you do, go lighter and think about how much the tyres weigh too. If you insist on getting those rims, invest in a decent set of coilovers and some kind of tune eg. OFT. It'll offset the weight and you get more out of the setup with coilovers than stock suspension (get's rid of that sluggish steering feel and bumps up the grip).

Anyway that's my 2c.

Hm, based off what I'm hearing I'm leaning toward lighter wheels. Any budget friendly suggestions, maybe XXR 527/530? Also, would springs (1 inch drop) instead of coilovers suffice?

XXR are heavy.

Budget friendly rims I'd rims I'd suggest would be 17x8 Enkei RPF1 or 17x8 Wedssport TC105N with decent performance tyre of choice. With these you can go for springs and it'll be pretty awesome. Checkout F1point4's build. He's got lowering springs and 17x9 TC105N. It poked a bit without camber adjustment and iirc he's got camber bolts up front and adjustable LCAs in the rear. Also, he rims + tyres weight a touch over stock but only a slight bit.

If you end up getting slightly heavy rims, springs wouldn't make you happy. It'll improve the handling a bit but you'll want to go for (at least two-way) coilovers to adjust the dampers to improve steering response and handling to where you want it.

Right acceleration is not noticeably slower at all. Yes stock ratios will give you better gas mileage because the cruise rpm is lower. I have Hotchkis springs so 20-25mm drop. Not much because I dont want to deal with camber adjustment parts and scraping speed bumps, driveways, etc.

Like the others are eluding to you need to get big brand name wheels to go lighter. The Miro's are low pressure cast which is the typical OEM process so no issues in strength just 2lbs heavier.

I considered looks as well as performance. There certainly is subjectivity or personal preference to appearance as well as performance enhancing qualities when choosing a tire and wheel combo.I went with a 16” Weds SA15R because I thought it was a good looking wheel and light.These wheels weigh around 14.6 lbs. The tires you are looking at the Michilen Pilot SS weigh 22lbs for the 225/40/18 and the 235/40/18 weighs 23lbs. Also the tire in this size is larger than stock which the 225/40/18 is 25.1” and the 235/40/18 is 25.4” So if the wheel weighs 23lbs and the tires 22 -23lbs we are looking at 45-46lbs per wheel per corner. If you went with a good street tire like a Continental Extreme Contact DW a max performance summer tire, which is a more comfortable and better handling tire than stock in either a 205/55/16 (at 19lbs) or a 225/50/16 (at 21lbs) If you considered the 16” option in either a, Weds, enkei rim, volk te37 11.??lbs , or a TWS t66f at (10.8lbs per wheel or so) you would be(w continental DW225/50/16 and a Weds SA15R) per wheel at 35.8lbs with a height of 24.9.or with a maximum lightness of a 205/55/16 Continental Extreme Contact DW (weight is 19lbs and height 24.9) and the 16x7 TWS (10.8lbs) you would weigh in at 29.8lbs per corner .So if you went with the TWS at around $600 per wheel and a 100$ Continental tire the 205/55/16 you would be a maximum of 16.2lbs lighter per corner.You would save a total of 64.8 lbs and the tire would be shorter in height and with a shorter height you will gain faster acceleration.This combo of the tws 16x7 wheel and the 205/55/16 tire should cost around 720 or so total.This is one of the lightest combos I know of.For a street car you would be just fine and probably more comfortable too with the softer sidewall of the 16” as appose to a 40 series.Anwyays you can’t go wrong there is subjectivity here, looks vs, performance. Vs cost.

Exactly why I went to a PSS in 245/35/18 its diameter is 24.7 and 22lbs. Remember the Miro's are 600-800/set of 4. Just depends how much that less weight means to you vs. expensive wheels. The savings on wheels could get you halfway to FI then a couple pounds of wheel weight don't matter much. Depends if you just daily or track. I autocross but just for fun.

Thanks! Some good points!