I have an offer for a set of stock wheels for about $400.

My FD is running on stock 18" RX-8 wheels that were installed by the dealer. Assuming the stock FD wheels are in good condition, would they be a good choice for an RX-7 that is 80% street / 20% track?

Obviously, the fancy aftermarket forged wheels would look cool and cost more, but the stock wheels might be lighter.

 

The tires are more important.

The advantage of aftermarket is you can run wider widths and have a lower profile sidewall if the wheel is bigger.

 

CE28N 17" are the best on FD (with JDM tires size) 235/45 ant 255/40 rear


Btw imho on FD3S and on street 17 are way better then 18 or 19

 

I'm running Pirelli P Zero Rossos on RX-8 wheels (18"/8" 225/45). Grip is fine, but the added unsprung weight is probably reducing my performance.

 

Pound for pound stock FD wheels may be the strongest choice out there.

 

That's my instinctive opinion as well. However, I'd probably have to check this set for pitting, cracks, etc... the cost of fixing/refinishing them may exceed the cost of new wheels. They do include a set of tires, but I didn't find out what kind.

In terms of fashion, the wheels I lust after are the Work Emotion CR, but I suspect they are cast, not forged. Also, I think they're really pricey. Also, the 2002 Spirit R (BBS) and 2001 Bathurst R wheels.

 

Ah ok...then forget the CE28N With 2 wheels you are over the price of 4 Emotion CR

 

I have done some research into the technical portion of wheel/tires and handling.

The best for handling are as wide of a tire you can fit under the wheel and also stretch the tire onto the wheel.

so basically you want the widest wheel you can fit on the front of the car, and then just match the rear.

The best diameter is 18". The tire compound has the best stiffness to grip ratio on a 245/35. 255/35, 265/35, 285/30, 295,30 tire. 17" isn't bad either.

Rim stiffness is more important than weight. the stiffer the wheel the faster the car at the limit. This was track tested using the same wheels of different weights (Enkei did the test in Japan with professional drivers). they tested a wheel that weighed around 21lbs and one that was like 17lbs? same tires, car, etc.

The current wheel, although looks are subject, for performance that meets the requirements above are 18x10.5 (+47MM) enkei PF01 with that offset. I think it will fit a stock bodied (rolled fenders) car with 265/35/18 or 285/30/18 tires. The second best options are 18x10 wheels with 255/35/18 or 265/35/18 tires. After that are 17x10 wheels with 255/40/17 tires (enkei rpf1, volk CE28N, etc).

If you try putting a larger tire on a skinnier wheel (255/35/18 on a 8.5" wide wheel) the contact patch will actually be less than that of a skinner tire on the same wheel (225/40/18 on a 8.5"). Its because of the dynamics and stifness of the tire on the wheel that creates a muffin top shape and distorts the patch for the worse. If you look at the stock rx7, they chose a 16x8 and 225/50/16 tire, which is stretching the tire over the wheel. they knew what was up.

articles for reference.

URGE designs

michelin engineer presentation slide 34 and on.
www.cb-racing.com/PilotCup_Presentation.PPT

 

Thanks for the info. I'll make sure to get a narrower tire on a wider wheel, then (muffin tops are bad for everything, apparently).

I am intrigued by the Michelin Pilot Super Sports... they look like the right kind of tire for me (the Sport Cups look more appropriate for competition use).

 

depends on what you want out of the car. the tires are everything, they accelerate, brake, turn the car, etc. all other mods manipulate the car on the tires, or stops and moves it. If you are modifying a car, I would say tires are the most important thing.

I only run extreme sports tires on my car for the street for this very reason. the tires are listed below. if you use your car as a daily driver, perhaps a max performance summer tire would be better for longer wear.

Extreme tires
RE-11, AD08R, R1R, XS, ZII, etc

 

Tires are not a choice to be made lightly on the FD. Because the whole chassis is designed for handling, it basically demands that the tires be up to the same ability as what the chassis is capable of.

I wouldn't run any larger than 18" at most.

I wouldn't run any lower than a 35 profile tire for the street, because you need that bit of sidewall meat to take up roughness, pot holes and undulations.

I would choose all-weather or all-season tires for the street, because the weather can be a big variable and you need it to be sure footed in all the conditions it is going to see in daily street use.

When we did Targa events, we once made the mistake of choosing a tire that was a little wider than the rim. This gave it a bit of the "muffin top" profile, and handling and cornering became more unpredictable as the tire "bag rolls" around laterally during cornering.

A tire that is the same width as the rim or slightly narrower (quarter to half inch narrower) is a good basic rule of thumb thing.

I would pick the larger wheel combo over the 16" stock wheels.

 

I might stick with my RX-8 wheels for now, then.

The Volk Racing CE28N forged wheels are very nice, but not really my style. I like the look of the Enkei PF01 wheels. They are about 17 lbs at 17"/8".

 

If you want an enkei PF01 wheels for a conservative fitment. I would choose a 18x9.5 +45. choose 255 35 18 tires.

If you want RPF1 wheels you can choose 17x9 and 245/40/17 tires. if you want to go aggressive and fender roll you can go with 17x10 +38mm 255/40/17 ot 18x10 +38 255/35/18.

 

Apologies for the necro post – I finally got Michelin Pilot Super Sports on my 18" RX-8 rims at 235/40R18 95Y front and rear.

I ran my last set of tires at 32 psi all around – I'll experiment with this new set and report back. It's riding on Eibach Pro-Kit springs and new Koni Sport shocks.

The tires are still on their break-in phase. I'm looking forward to trying them on the track when they're ready.

Also, I found out the RX-8 wheels are approximately 21 lbs. each.