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[blackboxing]

Looking to buy a new set of track/autocross tires. Was wondering if anyone has any experiences with the ZII's or Rivals? How are they in the rain? ZII's seem to be better in this aspect judging purely from the tread pattern.

Online reviews seem to agree that the Rivals are consistently faster in dry conditions and easier to drive well while the ZII's aren't as rewarding unless you have a very calculated car setup.

FYI, I'd be looking at 275/35/18.

Thanks in advance!

Edit*

And then, of course, there are the Bridgestone RE-11A's and the rumored Kumho V720...

[wooderson]

http://www.tirerack.com/tires/tires....omCompare1=yes

The Rivals are kind of heavy at 32lbs. each.

[aus]

How do they compare in price? I checked out the Rivals and they were $$$$$.

[slicer]

Pricing is very similar. It will be difficult to find someone with experience running the G-Force considering they have not released them in M3 sizing yet.

[CSBM5]

I have nothing but great things to say about the Rivals. I just PAX'd first out of 98 cars at an autox Sunday. I have the M3 setup for F-stock tire class -- our club runs an indexed tire class using SCCA PAX values. Anyway, I've had the Rivals for two months and have done three events -- two dry and one wet. I can't really comment on wet performance as I have nothing to compare them to, but it was ~40F and huge rain -- miserable event.

I've been autocrossing since 1976, and the Rival is by far the best street tire I've ever driven. The turn-in response will blow you away -- it's hard, sharp and instant feeling. They are able to be nicely modulated near peak grip. I'm still amazed at how hard the M3 hooks up off of elements. Part of that is likely due to the large Dinan front sway bar of course, but it still is just amazing to me at how well this car is on course.

Mods are limited to stock class rules: Dinan front sway bar, pins out for max negative camber (~-1.6), stock width TRMotorsport wheels (8.5, 9.5), and then 245/40 Rivals. Only the 245s were available (until June when 275s come out), so I went with them. I'm very pleased with these so far, and I really do not want to run a stagger tire size in the future as the balance of the car is almost perfect. I will consider running 275/35s all around when these wear out.

Here's my fastest run from Sunday (1st PAX, 5th Raw, on street tires ):
https://www.youtube.com/watch?v=c5VpjPytJis

[blackboxing]

Thanks for the replies guys. The tires are priced very competitivelytowards each other; in the size I'm looking for, they are actually the same price.

Originally Posted by CSBM5

I have nothing but great things to say about the Rivals. I just PAX'd first out of 98 cars at an autox Sunday. I have the M3 setup for F-stock tire class -- our club runs an indexed tire class using SCCA PAX values. Anyway, I've had the Rivals for two months and have done three events -- two dry and one wet. I can't really comment on wet performance as I have nothing to compare them to, but it was ~40F and huge rain -- miserable event.

I've been autocrossing since 1976, and the Rival is by far the best street tire I've ever driven. The turn-in response will blow you away -- it's hard, sharp and instant feeling. They are able to be nicely modulated near peak grip. I'm still amazed at how hard the M3 hooks up off of elements. Part of that is likely due to the large Dinan front sway bar of course, but it still is just amazing to me at how well this car is on course.

Mods are limited to stock class rules: Dinan front sway bar, pins out for max negative camber (~-1.6), stock width TRMotorsport wheels (8.5, 9.5), and then 245/40 Rivals. Only the 245s were available (until June when 275s come out), so I went with them. I'm very pleased with these so far, and I really do not want to run a stagger tire size in the future as the balance of the car is almost perfect. I will consider running 275/35s all around when these wear out.

Here's my fastest run from Sunday (1st PAX, 5th Raw, on street tires ):
https://www.youtube.com/watch?v=c5VpjPytJis

Thanks for the detailed insight. Is it safe to assume that you're comparing the Rivals to other popular tires for autocross/track (IE. RS3, Z1 and AD08)?

[blackboxing]

Just saw the video...nice driving! Holy crap, they're noisy.

[CSBM5]

Originally Posted by blackboxing

Just saw the video...nice driving! Holy crap, they're noisy.

The pavement at NCCAR is extremely grippy, but the Rivals love to talk according to those that have used them and BFG/Michelin. It's nice to get them talking to you just as long as they aren't screaming too hard. They like slip angle, and have a nice top of curve (tractive force vs slip angle) grip over a wide range. Take a look at that sweeper at the far end of course vs my steering inputs for example.

I'm comparing them to my most recent experience which is autocrosing Star Specs on my daughter's E46 and NT-01s on my M5. Prior to take it was BFG R1 and Hoosier A6 (which of course these other three aren't street tires). NT-01s love to sing to you too near their limits.

I've only had the M3 since February and only for three events, so I'm still climbing the curve learning the car although it fits perfectly with my past experience so far.

Regards,
Chuck

[lcrain]

Bumping this up. I need new tires. Coming from RS3s which I loved, but they are scarce and expensive so looking at these two options. For what it is worth, I would be running 265/285 in the z2 and experimenting with 275/295 on the rivals.

Any feedback would be great! Thanks.

[CSBM5]

I ran the Rivals all last season with excellent results, PAX all in top few spots. I just bought a set of 275/35 Rivals, and even though I have to run them on 8.5/9.5 wheels due to SCCA rules, they are working superbly -- ran them this past weekend at a CCA autocross at the BMW PC, and I'm very pleased with the 275s all around. Amazing grip for a street tire, forgiving, etc. Snagged FTD overall for the event.

I'll have more feedback this autox season once it gets underway on the 275s on stock wheel widths, but so far the fronts (main concern running them slightly pinched on 8.5" wheels) are working out wonderfully.

I have a second set of spacers in case I want to try out 295 Rivals out back (if I buy a couple more rear wheels), but so far after Sunday's event at the PC, I don't think I want the 295s out back for autox as I was getting just about the perfect amount of rotation out of the tail with the way the car is setup. I'd be concerned that on tighter autox courses, the 275/295 setup would not yield enough rotation in slower speed sections.

[M3 Esq]

I ran the Rivals for a few track events last year. Very grippy and communicative. Stiff sidewall. They didn't seem to get greasy on me and felt fairly consistent. I'd use them again.

[lcrain]

Cool. Thanks for the replys, I think I am going to bite the bullet on a set. Decided to ditch my staggered setup for a square setup in the meantime.

[M3 Esq]

Originally Posted by lcrain

Cool. Thanks for the replys, I think I am going to bite the bullet on a set. Decided to ditch my staggered setup for a square setup in the meantime.

I ran a square setup too. They're asymmetrical so you can rotate back to front and side to side. That was one reason I chose them over the Dunlops. Those are directional so you can't rotate side to side.

[Golddots]

Csbm5,
Do you have any clearance issues at all with 275's all around? Does it barely fit up front?
I would like to play in FS this year and I'm considering going to 18s for better tire selection.

Any recommendations for offset to fit?

Thanks.

[CSBM5]

Originally Posted by 414hpbabyshuttle

Csbm5,
Do you have any clearance issues at all with 275's all around? Does it barely fit up front?
I would like to play in FS this year and I'm considering going to 18s for better tire selection.

Any recommendations for offset to fit?

Thanks.

No problems at all...plenty of room up front. I'm using TRMotorsport wheels (the fronts are NLA now from TireRack) in stock widths, of course, 8.5" and 9.5". The wheels are manufactured with a 44mm offset on the 8.5 and 35mm offset on the 9.5. I'm using 18mm spacers all around. This gives a net offset up front of 26mm, so that is 3mm further outward than stock. In the rear it gives 17mm which is 6mm further out than stock (note the SCCA max offset change rule is 0.25" or 6.35mm).

I have a set of 12.5mm spacers for the rear in case I needed them, but the 275 Rivals have shown no rubbing using the 18mm.

Up front as long as you stay at stock (29mm) or less (I'm at 26mm), I don't think you'll have any problems up to the rule limit (23mm). In the rear, there is plenty of room, so anything from the stock offset, 23mm, out to 17mm should work fine. I had pondered trying the 295/35 Rival in the rear (and would use my 12.5mm spacer if I did to give a net offset of 22.5mm, essentially stock), and it should fit; however, after my recent experience at the Performance Center autox, I'm happy with the hookup in the rear, so I'm sticking with the square setup for now.

Regards,
Chuck

[slicer]

I love that the G-force Rival is available in 295/35/18. It's the next tire I plan to try.

[Golddots]

Thanks for the reply chuck. That was the most help I've found on all the searching I've done online.
In one post to boot!

[ashtaron14]

Just mounted 245/40/19 & 275/35/19 ZII on 220M.

Only driven on them for 2 days. I'll write about them when I learn more about them.

[slicer]

Originally Posted by ashtaron14

Just mounted 245/40/19 & 275/35/19 ZII on 220M.

Only driven on them for 2 days. I'll write about them when I learn more about them.

That front tire size will rub like crazy on the back of the fender liner when you turn. It's a full inch larger than OEM (245/35/19). The front of the car is sensitive to the tire's overall diameter.

[Richbot]

Originally Posted by slicer

I love that the G-force Rival is available in 295/35/18. It's the next tire I plan to try.

This is the main draw for me too. Plenty of room for a 305/35-18 with the right wheel but i will settle for what's available, i hear custom tires are expensive, lol. I don't like how thin the sidewalls are on the 30-series 18" options out there

The Conti DW is the only other half decent street tire offering these sizes outside of the wacky expensive realm anyway

Im using the same wheels chuck is (actually i think im the one who gave him the idea, lol) with 15mm front and 12.5 rear spacers. This yields essentially stock offsets which has been enough room to very comfortably fit the 295/30 and 315/30 hoosier. So if the best clearance possible is a goal, that helps. I tend to prefer narrow as possible as every mm counts when you are driving close enough to the cones and this car is already wide. However the spacers chuck is using eill effectively soften the car especially in the rear thanks to the wider track, which probably helps with rear traction on street tires

[ashtaron14]

Originally Posted by slicer

That front tire size will rub like crazy on the back of the fender liner when you turn. It's a full inch larger than OEM (245/35/19). The front of the car is sensitive to the tire's overall diameter.

Haven't rubbed, didn't hear anything unusual, other than that this tire gets a very obvious humming like that of R-compounds once it gets to 100km/hr