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rlekun
03-17-2003, 10:44 AM
Okay, I've been searching old threads here and on the SCCA forum, as well as GRM magazine. I've been thinking about changing from Hoosiers to Kumhos just to save a few bucks, but not if it's going to cost > .5 seconds a lap (at say M-O). Any 1st gen RX-7 with Hoosier experience using kumhos? Are you using the victo or Ecsta (if Ecsta what size, since they don't make 205/60 or 225/45 in 13")
Some people say the Kumho's wear much longer than Hoosiers, yet others don't seem to get much greater wear...just less prone to flat spotting.
Opinions (based on experience) please!

Hotshoe
03-17-2003, 08:09 PM
The Hoosiers will give you .7 sec over the Kumhos. And will give you .5 sec over Toyos. They will not last as long as the Toyos but stay more consistent between heat cycles. I get at least five races out of a set of Hoosiers. I used to run Toyos but the times fell off to much after three heat cycles. Kumhos are even slower after two heat cycles.
I hope this helps. I've done quite a few test with different tires. I have even tried tires that are pure street tires just to see how they perform. For test days and tuning I use a set of BF Goodrich TA Radials that are shaved to 4/32 tread. It lets the car slide around alot but gives me a good feel for what the chassis set up is doing. It also helps me with my WET feel. I hardly ever race in the rain but with street tires on I have learned the line at most of the tracks that I run.

Rick Thompson #99 IT7

[This message has been edited by Hotshoe (edited March 17, 2003).]

rlekun
03-19-2003, 03:44 PM
Still looking for input.

Related question...I'm leaning toward staying with Hoosiers but going to the 225/45 13". Has anyone had issues with contact with springs? I use the Groundcontrol sleeve and spring combo up front.

Also guys and gals, has anybody had any experience with the Goodyear Eagle GS-CS? I believe it too is an R compound tire, only available in 205/60 for 13" rims....

[This message has been edited by rlekun (edited March 19, 2003).]

Dave Burchfield
03-19-2003, 06:10 PM
Your best bet for information on the Goodyear on a rear drive car could be Larry Morris. He drives a Datsun 240Z(white #75) for a number of years now, and is pretty competetive. He's been using them for quite some time. You will fing him on the internet at Mojo Racing. John Herman uses the Goodyears, but his car is FWD.

db

Quickshoe
03-19-2003, 06:32 PM
rlekun,

I don't know you so don't be insultated by the word "you" as it applies to everyone contemplating the same issue.

How much time would you be willing to give up for how much of a savings?

If you are maxing out your budget buying fresh Hoosiers 3-4 times per year, and swithced to 2 sets of Kumhos per year, what would you do with the money you saved? About $1600/year might lead you to legal upgrades elsewhere on your car netting a bigger advantage in lap times. A couple of extra races per year might lead to being a better racer.

rlekun
03-19-2003, 07:12 PM
Quickshoe, your point is well taken and precisely why I'm asking the question. I'm trying to understand the amount of the trade-off. In an old GrassRoots Motorsports, there was a side by side comparison showed the Kumhos (Victo's I think) were only about .15 seconds slower than the Hoosiers when tested by 2 or 3 different drivers on a road race course. That trade-off I can make, but if its a full second a lap difference, forget it.

The problem is, the more you hear/read the more confused you get. For example, on the Corvette racers forums, they seem to love the Kumhos.

I actually get pretty good life out of the Hoosiers, so its not the usable life thats the issue for me. What I don't like about them is 1) that they seem to go away a bit later in the race...probably as a result of my overdriving them, and 2) the d@mn flatspotting.

The Goodyear option intrigued me. They're actually even more expensive than Hoosiers. I can't find for sure if the GS-CS is an R compound, but I beleive it is. Some of the other forums say that they're as sticky as Hoosiers but wear like Kumho's. The Goodyear site lists it as a "Showroom Stock Racing tire". But then again, the runoff podium positions seem to always be dominated by Hoosier.
As stated above, I'm leaning toward staying with Hoosiers but going to the 245/45/13. If I do, I guess I'll buy a couple of extras.

C. Ludwig
03-19-2003, 09:32 PM
On my ITS RX7 at Mid-Ohio I picked up about .3 sec on Hoosiers over Kumho Ecstas. The Ecstas I used last year were molded in the old compound. IMO the Kumhos were easier to drive and more forgiving. I'm looking forward to getting some of the Kumhos in the new compound. The price difference for my size from tire rack is $40/per tire. I can get a deal on Hoosiers and cut the difference to $20/per. Even with that I'm gonna stick with the Kumhos and try the new compound to see what we end up with. But I like to be different...

Chris

------------------
Chris Ludwig
08 ITS RX7 CenDiv

ITSRX7
03-19-2003, 09:48 PM
We use only Goodyears. The GSCS is THE BEST road racing tire in our opinion. Blows the Kumho's away and is equal to the Hoosier but temps stay more consistant - so over a complete race you are faster.

YMMV. The testing was done in New England.

AB

------------------
Andy Bettencourt
06 ITS RX-7
FlatOut Motorsports
New England Region
www.flatout-motorsports.com

Hotshoe
03-20-2003, 04:28 PM
Not to beat a dead horse but the Hoosier Tire to me is faster over the long haul. I had the privilege of co-driving in a three hour enduro at Lowes Motor Speedway two years ago and everyone was talking about running Toyos, Goodyear R1's, and even Yokohamas. We decided to stay with the Hoosiers because we already had a feel for that tire and the car was also set up for the Hoosiers.
I was impressed with the tires performance. We ran the entire race on that one set of tires. Finished 3rd. overall first in class. Not bad for an IT7 car. The only cars ahead of us were the two BMWs and we were only one lap back from the lead one. And on the same lap as the second place BMW.
The tires still had over 1/4 tread left at the end of the race. No flat spots (which is good for Charlotte )and we used them for a complete test day at Roebling Road.
Saying all this doesn't mean that there isn't any other good tires out there so please don't get me wrong. I'm just saying that from my experience I would stay with the Hoosiers.

Rick Thompson #99 IT7

Weaver7
03-22-2003, 05:16 PM
Originally posted by rlekun:
Still looking for input.

Related question...I'm leaning toward staying with Hoosiers but going to the 225/45 13". Has anyone had issues with contact with springs? I use the Groundcontrol sleeve and spring combo up front.

Also guys and gals, has anybody had any experience with the Goodyear Eagle GS-CS? I believe it too is an R compound tire, only available in 205/60 for 13" rims....

[This message has been edited by rlekun (edited March 19, 2003).]

I also wondered if there is an issue with this size tire for clearance. Does anyone know if this size handles better or worse??

rlekun
03-25-2003, 11:27 AM
Weaver7,
I guess I'll find out soon on the clearance issue. Ordered a new set of 225/45 13 last week. I'll let you know what I find out. I checked the specs (tirerack site) and I don't think there will be an issue. I guess anytime you can lower the car its to your advantage and the 225/45 is 2" shorter that the 205/60 and the tread section is slightly wider (if memory serves me correctly) also the shorter profile avoids the fender clearance issues (no one ever actually adjusts the sheet metal to improve clearance right? because that would be illegal http://Forums.ImprovedTouring.com/it/wink.gif )

Karl Bocchieri
03-25-2003, 12:57 PM
The Goodyears seem to be the largest squarest tire, the Kummo's are the smallest and the Hooser's seem to be wide but not as tall as the Goodyear's. (All the same size by the way)
Goodyear's are fast, take awile to warm up, ok life span.
Hoosers are also fast, shorter warm up time, lasted a race or two longer than the GY, lightest tire.
Kummo's are 1-1.5 sec slower, take alot more abuse, last forever, but get slower even though they have lots of rubber left, and are less expensive.(old compound v700)
IMO.

Does anyone have any experience with the Michelin Pilot Sport Cup. PCA drivers have great things to say about them but I wonder how they are compared to the Hoosers and GY.

Can you get the new compound ECSTA V700 and how do they compare?

Weaver7
04-06-2003, 12:21 PM
I see that they offer 2 sizes 225/45 13
and a 225/50 13 What size is the best?? Getting ready to order a set and with the new season approaching quickly I have to order them soon.

04-06-2003, 12:46 PM
it seems for IT7 or ITA RX7's 225's for the rear and 205's for the front would equalize the handling, its the rage in pro7 in the west right now only with one size smaller 185/205.