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Rivals vs Zii vs RE11?

[size=10pt]Questions are in green and ranting is black

I am thinking to get myself a set of 18X9.5 GT500 wheels from rehagen racing
http://www.rehagenracingproducts.com/2005-2014-Ford-Mustang-18-SVT-GT500-Wheels-2010-Shelby-M-1007-DC1895.htm?categoryId=-1

I am torn in between Rivals 245/275 and Zii 245/275? [size=14pt]
Which one?
On the other hand the RE11 can get wider size selections for the 9.5 rims, 285/265...etc
They will be for the track, no DD. I went with street tires due to their tread life.

With the Zii, compared to rivals, they have wider tread width which is a plus, however they carry a small slip angle, not so much tolerance for idiotic steering inputs compared to the rivals where they are more forgiving.

The most forgiving and progressive of the group with the best wet traction are the RE11 in addition to more meat available, however the dry traction is a little compromised.

I am also wondering, isn't 245 upfront too narrow? On the flip side, doesn't the 245 translate into a better steering feel and feedback? I got that info from Jamal Hamidi, the SVT guy.

Now one more question, if I go with one of the above setups I am shedding only $1690 ( $1010 tires and $680 wheels) as compared to Enkei PF01 18x10.5 all corners, for wheels only we are talking $1500+ and tires will be $1200ish, so total of $2700!
1K difference, does it make sense for the extra rubber and lighter wheels? I am a novice to advanced novice driver...
The problem is that I KNOW I will eventually go for wider wheels and tires, I know that, but shall I just go big from the beginning or start low and slow and I can always sell those GT500 wheels for something...

One last thing, does anybody know the actual weight of those wheels too
http://www.rehagenracingproducts.com/MUSTANG-SHELBY-GT500-WHEEL-M-1007-S1895.htm?categoryId=-1?
Are they lighter than the first wheels in the post or the same?
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Our cars are heavy and need more rubber not less. I suggest the Rivals in 275/295 widths. Get wheels to fit the tires not the other wat around. ;)
 
I’ll try to answer the questions based on my limited knowledge and personal opinion.

Tire sizes.
I personally would not go a size smaller up front, just because these cars are nose heavy and you may experience mid-corner understeer. It is true that a narrower tire may give you a better turn-in, but that will quickly translate to mid-corner understeer as the front outside tire gets loaded and exceeds its grip. And as the tires slide, they will overheat, get greasy, and you won’t be very pleased with the performance. Then again, as you mentioned, the ZII 245’s may be equivalent to our stock 255’s.

Tire brands/models
Both tire models seem to be pretty decent. I have not run these tires, yet. But at the end, the tire size you decide will probably dictate the tire model. Have you considered square, 275/285 all around?

Wheel size
I’d consider 18x10’s from the get go. You’re going to take a hit on the 18x9.5 wheel values anyways, why not purchase something that you can use in the future, as you progress. If enkei’s are a little expensive, look into some of the replica wheels sold by LMR and AM (e.g. SVE Drifts), or the Team Dynamics from Blowfish Racing.

Good luck with your choices!
 
NFSBOSS said:
Our cars are heavy and need more rubber not less. I suggest the Rivals in 275/295 widths. Get wheels to fit the tires not the other wat around. ;)

Good news! I was just talking to Tire Rack today about RE-11's in 285/35-19. I learned that the Rivals will be available in the next couple months in 255/40-19 and 285/35-19! I suddenly an losing interest in the Bridgestones.
 
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FWIW I went with Z2's in 245/275. At least in the 19inch sizes, they are identical in tread width to our factory P zeros. So you lose nothing with that tire.
If the Rivals are truely 245/275 (ie: they do not run wide like the Dunlops), then it may not be ideal. I understand that the Z2s run a more narrow slip angle (just like Z1s did). but IMO it's not a big deal. Our cars require very little steering input to behave properly. The requirement to dial in more steering is not really a tire issue but perhaps a driver issue. And yes, the rear end can skate around a bit. But unless you're on a crazy hot lap in a time attack, it's no big deal. In any normal track driving situation where you are not on it 10/10ths, the Z2 will mroe than suffice. Watch that rear pressure and it'll be fine even at 10/10ths.

I would state that the Z2 traction characteristics suit the performance envelope of our stock car. The Boss has a narrower performance envelope. The Z2s work fine within that envelope. On the other hand, if you like to be more ham fisted and over drive the car often, then Rivals are certainly going to be more forgiving.
 

Grant 302

basic and well known psychic
The GT500 rims are heavy. Go with lighter 18x10s. You can still run staggered tire sizes if you want on those. 275s on 10" rims provide excellent steering feel.

I've driven on RE-11s on a friend's WRX. Good tire, but I'd wait for the new RE-11A in larger sizes before I'd try those again.

Just picked up a used set of Rivals in 275/35-18.
 
Buy wheels once not twice. The Zii have the most grip, the Rivals are the most forgiving in the dry and the RE11s are the best all around wet/dry compromise IMO. It all depends on your priorities. The Zii can be flipped on the wheel to get maximum tire life while the others cannot. 275 ZII square is my choice on 9.5
 
[size=10pt]I think I might go with "go big spend once" theory.
I have been eyeing Enkei PF01 18X10.5 for a while, I am stuck at the offset area now

Options are:

1) Offset +38mm all corners
Pro: you need a thinner spacer at the front
Con: at the rear the 38 will stick out slightly that might create a rubbing issue on lowered cars.
Sam Strano said he has not seen or noticed any rubbing issues with 38 at rear.

Conclusion: overall they are easier to rotate.

2) Offset +47mm all corners ( Cortex racing)
Pro: your rear will tuck in under the fender without rubbing issues
Con: a) you need a fat spacer at the front
b) since the 47 offset tuck the wheel in so much, you might face issues with some lowered cars coilovers and sway bars touching the wheel inner side
c) more expensive per piece
d) very minor con, they come in black, but I prefer silver


Conclusion: they are slightly difficult to swap due to the spacer issue

3) Offset mix 38mm and 47mm
Basically you will get the mixed pros and cons

Conclusion: you will have to have 2 spacers available according to the wheel you choose to rotate, if 38 you use the skinny spacer if 47 you have the fat spacer ready.
 
I'd go with +38.
Did you decide to go square? since you mentioned front to rear tire rotation.

I think the spacers are only needed up front to make sure tires clear the shocks and endlinks. If you go 245/255s up front, don't think you'll need the spacers (unless the wheels don't clear the brembos either)
 

Bill Pemberton

0ld Ford Automotive Racing Terror
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I would get a set of Enkeis and call GT Racing ( Wisconsin ) . Get a set of Continental Slicks ( made by Hoosier and essentially an endurance R6 ) that were used in the Series and though used you can get them for $100 each. With a little shipping and set up a full set for a bit over $500 and you can run 305s on the rear and 285s on the front.

Those heavy rims are just not the way to go imho!
 
As you can see, the right front tire wearing is very bad and it is due to the toe angle being off

My alignment before and after, just done with it a few hrs ago

1t21f.jpg
 
So what size tires did you settle with?

Now, like me, you can enjoy and appreciate the rear tire gap, just don't stick your head in it, you may get stuck :p
 
F.D. Sako said:
So what size tires did you settle with?

Now, like me, you can enjoy and appreciate the rear tire gap, just don't stick your head in it, you may get stuck :p
295/35-18 Rivals
 
Grant 302 said:
Wow. Those before figures explain the bad front tire wear!
It is literally destroyed ( almost).
I went with -1.5 camber instead of higher number, because of 2 reasons:
a) keep the gap between the tire and stud bigger, although I still have 5mm spacer
b) slightly cut down on the front grip to have a small room for the "safe" understeer

Today I will install the 20mm rear sway bar ( takeoff from 2005-2009 GT)
And on the 16th, 17th and 18th of May I might be at MidOhio to test this new setup!
 

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