E30 STX Tires - 205 RE71R vs 225 Rival S

Seems like these two were the street tires to beat last year. Unless it sounds like there are new, better tires for next year, I'm planning to run one of these on a 15X8 TRM C1 square setup.

205/50/15 Bridgestone RE-71R
225/45/15 BFG Rival S

My inclination is to go with the wider tire, but with stretching the 205 on an 8" wheel I'm not sure there's all that much difference. My friend is suggesting the smaller RE-71R's will be as fast or faster for a lower price (he drives an STU Corvette with Ohlins and 275 square RE-71R's).

Currently the car is on 440/650 Ground Control coilovers (w/ custom valved Konis) including the pillow ball upper mounts.

What do you guys think? On the E30 is there a tire that will perform better than the other?

My feeling is that stretching a 205/50 on a 8 inch is going to make for a sticky but VERY peaky-at-the-limit style of handling. Also, 225/45 is just about "ideal" on an 8 inch. It's also hard to argue against nearly 3/4 inch more rubber at all four corners. Add to that the fact that the Rivals are known to have a fairly wide slip angle plataeu at max cornering G, and the 225/45 should produce more cornering force while also being more forgiving of ham-fisted moments.

I tend to advise people the other way, I.e. If you are at the point of asking a forum what tire to run, you will likely find the RE71R easier to drive fast and consistent. They are precise, quick to turn in when asked, and you can get away with more mistakes / late inputs and still salvage the run. The rivals require more discipline and leading the car...its harder to extract every ounce of grip consistently so having a smidge more width / grip available may not matter if you cant use it. If you find that by the 4th cone in a slalom you are playing catch up or reaching for the brake pedal...buy the RE71R (and work on staying ahead too).

On a 7.5" or smaller rim, id pick the 205 RE71R all day long. I consider that proven. On an 8" you might have to flip a coin. That coin might be cost.

Fastest wheel width for a 205/50-15 is a 15x8. Fastest wheel width for a 225/45-15 is a 15x9. It's not peaky.

I run a 205/50R15 on a 15x8" rim and the stretch is barely noticeable. As for the tires themselves, all the cars at the top of our Solo chapter were running the RE-71Rs. Everyone I talked to about them said they were an absolute night-and-day difference over the tires they were using before and they regretted not getting them instantly. Apparently they are that good

I may need to reconsider my own width/wheel ideas. Then again, my bias is ITB where we are stuck with a 15x6 max wheel size, so pinching vs. squeezing leads to some interesting compromizes for IT racers. Just do what Keith do RE-71R is also being strongly suspected of being a "cheater" compound in terms of "true" 200 treadwear class tires and that Bridgestone did it on purpose. Not only because of the nearly R-compound level of grip, but the giveaway appears to be that they only last HALF as long as virtually every other 200 class tire.

Red GT hit the nail on the head. The reeeeeealy fast guys seem to be able to go fast on the Rival, but if you're still working on becoming one of the fast guys, the 71 is better. I'm not sure about the 205 (mine aren't here yet) but my 275 71's are wide 275's. I should be able to give you a measurement this afternoon, but I imagine you're looking at putting an 8 inch tire on an 8 inch wheel, which is ideal.

This is great feedback guys, greatly appreciated. I have a couple years of experience, but that was almost 10 years ago at this point. It sounds like I should probably go with RE-71R (unless people think they may get banned from STX) based on cost & forgiving behavior.

I would love to run a 15x9 but that will not be an option on an STX E30. The car will prob end up in SM at some point, but that's a discussion for another day.

In reply to WildScotsRacing:

Idunno, I have like 5000 miles and 160 some runs on mine and they are just now at the wear bars and still fast. That's about as ideal for this sport as you can get. If its a cheater tire, whatever, lets have a few more brands build one.

I put 6000 miles and a couple dozen track laps on mine last spring. Since then I drove another 1000 miles on them and have 6 autocrosses. Just now they need to be flipped and should have a couple thousand more miles and another half dozen events. This is on a 4400lb car. Some people are reporting excessive wear, but others aren't. Still not sure what to make of that, but I'm happy with them. They're also very good rain tires for the first half of their life, better than many of the other contenders.

I...ah...this is not going to help the 'cheater' argument, but I did kinda heat cycle mine. 15 minute gentle drive to work. They got HOT despite it being a leisurely drive in March. They sat for 9 hours, followed by another 15 minute gentle drive home in which much, much less heat was generated. Took them off the car and let them rest for a day just in case. Not an ideal heat cycle approach like some people swear by for Hoosiers, but I suspect half-assed is all it takes, and I bet lots of people did so inadvertently because they put their shiny new tires on, went for a fun little drive, and then parked the car for a work day, or overnight, or whatever. Other people happened to not do this and have a wear problem.

*caution, this particular post is 80% speculation and crackpot theories. Don't take it too seriously.

Interesting......the first thing I did with mine was drive them from Texas to Indiana which I'm pretty sure counts as a heat cycle or two. I'll have to make sure I do some cycling on the new ones just in case.

If only there was a magazine which produced a test article on these two tires. Wouldn't it be neat if this theoretical magazine could also run some tests to help readers determine the optimal wheel width for a given tire width? ...wait what's that thing in my mailbox from a few months ago? ;)

There is also that. Heh. I was not subscribed at the time and kinda forgot about it.

RedGT wrote: There is also that. Heh. I was not subscribed at the time and kinda forgot about it.

Oops, me neither... Anyone have a link they could post?

The thing is that the magazine test results contredict the real life results. Like others have said, I think a really good driver will be able to extract the max performance from the Rival, but the RE-71R's are just plain easier to drive.

I have absolutly no regret from buying my RE-71R's. I will chant their gospel loud and clear.

And after one season of use, they are showing very normal wear for a 200TW tire for me. But I will say that after the first event, I really thought they wouldn't last me long. And it was the same for everyone that was running them. They were showing signs of chunking on the edges. But after that day, they smoothed out, and they have been great.

There's also the weight/gearing issues, but unfortunately I don't know enough about the SIZE of the effect weight/gearing has.

Gearing is easy, shorter is faster, unless it forces an extra shift.

Weight causes acceleration losses, and affects the suspension. Lighter is generally better of course. Remember the weight difference is multiplied by 4 (4 tires), and this weight is in the WORST PLACE POSSIBLE - unsprung, rotating, and at the furthest point from the axis of any other rotating weight on a car.

So, now I have probably not helped at all, only further complicated your decision. I remember an RX8 comparo a while back tested (IIRC) 245 vs 275 with just about all else equal. They did not find the 275 to be appreciably faster.

I've got very little seat time on the Rival - if I want a tire that compromised for street use, I usually go straight to an R compound as class restrictions don't matter to me. But I have got some time on the RE71R on the ND. Granted, it's a new platform. But it shows no signs of overheating (unlike an R1R) and it sticks like crazy. I'm digging them.

I did several events on the Rival-S last year in an STX RX-8, and then for nationals we borrowed a set of 1 event RE-71Rs. Although the BFGs were very good, especially in sweepers, the transient response of the Bridgestones killed the BFGs in fast offsets and slaloms. That being said, the BFG rep at Lincoln said they are updating the tire for 2016 to have a stiffer sidewall on par w/ the RE-71R, so that tire might be the one to have in '16, since Bridgestone has said they are only adding sizes and not changing the tires themselves for next year.

In reply to boileralum:

Now THIS is going to be interesting to watch play out nexr season!!!