Enkei RPF1 17x8 or 17x9 ¿?

[donoman]

Any rubbing on a 245/45-17 R-Comp like the R888, etc with the 17x9 ET35 RPF1? I'm about the pull the trigger.

[GSpeed]

Originally Posted by rx3

I tried the Michelin Slick mentioned above on a very tight course. (1 min 30 seconds long; 30% was in 1st gear)
There's a substantial difference compared to the Toyo R888. The rear wouldn't break out at all as it usually does (for instance, accelerating out of a tight u-turn). This was the first time that I had to say that differential does not suffice, as it would let the inside wheel spin on a regular basis.
Even shifting from 1st to 2nd at full throttle in a turn barely got the rear to move.

The grip is very impressive it feels almost as cheating.
Because of it it's also less fun to drive because it's easier to control the car.

In short, it was a very easy win in the class I ran (sort of like STX on slicks with the difference that my car is mostly stock).

Also, since the diameter of the tires is relatively small (only 605 mm), all 4 wheels can easily be placed onto the rear seat area (so the trunk can be used for other things.)

Attached is a picture of the tire on a RPF1 17x9 rim (offset is 45mm in the rear and 35 mm in front):

How long was the race? What were your temperatures? I'm curious how the S5B compound held up.

Jake

[zdr93523]

Originally Posted by Toyota GT 86

Thanks, I finally got 17x9+35 with Hoosier A7 245/40 all around

What organization/class are you running in?

[rx3]

Originally Posted by PST

How long was the race? What were your temperatures? I'm curious how the S5B compound held up.

Sorry for the late response.
I've meanwhile run them at 3 events. (I only run on slicks when my roadtire-field has not enough participants, such that I need to run in the slick-field in order to collect more points).

The first event was 1:30 minutes per run (asphalt, 4 runs). Temperature was around 20 C. They were sticky from the get-go (no warm-up time). Even in first gear sweeper turns the rear wouldn't break out (differential struggled to lock up).

Second event was about 1 minutes per run (asphalt, 4 runs). Temperature was also around 20 C. Track was a little dusty and the rear would occasionally break out.

The third event was 3 minutes per run (asphalt, 4 runs). Temperature was over 30 C in the afternoon. It appeared as the tires may have lost some of the grip at the end of the runs, but they didn't get any greasy. I was just faster in the morning, when it was cooler.
At this event the rear occasionally broke out even though the track was clean (so maybe the slicks do heat cycle out early. They also wear out quickly. Other people on Honda Integra DC2 have to get new tires every 4 events (16 runs), but they also run on 15" tires).

[rx3]

Here's a video of one run of that last event:
[ame="https://www.youtube.com/watch?v=ebo6jNbQ_II"]Slalom/Autocross on Michelin S5B - YouTube[/ame]

[MaximeT]

Originally Posted by rx3

Here's a video of one run of that last event:

Nice video. I like the 48p.
I dunno much about auto X, but that's faster and with more obstacles than I thought. Looks like a flat hill climb at some point.

I'm looking at using the harder Michelin myself (s8 I think) on the track. As soon as I get a car
My reason to switch to this car is to use this tire (cargo space)

[GSpeed]

Originally Posted by rx3

Sorry for the late response.
I've meanwhile run them at 3 events. (I only run on slicks when my roadtire-field has not enough participants, such that I need to run in the slick-field in order to collect more points).

The first event was 1:30 minutes per run (asphalt, 4 runs). Temperature was around 20 C. They were sticky from the get-go (no warm-up time). Even in first gear sweeper turns the rear wouldn't break out (differential struggled to lock up).

Second event was about 1 minutes per run (asphalt, 4 runs). Temperature was also around 20 C. Track was a little dusty and the rear would occasionally break out.

The third event was 3 minutes per run (asphalt, 4 runs). Temperature was over 30 C in the afternoon. It appeared as the tires may have lost some of the grip at the end of the runs, but they didn't get any greasy. I was just faster in the morning, when it was cooler.
At this event the rear occasionally broke out even though the track was clean (so maybe the slicks do heat cycle out early. They also wear out quickly. Other people on Honda Integra DC2 have to get new tires every 4 events (16 runs), but they also run on 15" tires).

Very cool event, thanks for the video. Looks like a ton of fun. What camera are you using? (Sorry for all the questions.)

[rx3]

Originally Posted by MaximeT

I'm looking at using the harder Michelin myself (s8 I think) on the track. As soon as I get a car
My reason to switch to this car is to use this tire (cargo space)

What's nice is that these tires are available with a 605 mm diameter, which is just small enough to fit all 4 wheels in the back seat area. Btw, the Avon slicks are also available with that same diameter (and width). (Hankook slicks would be cheaper but they are not available in that dimension, but I might try them anyway because we need to use first gear quite often and I'd prefer if the first gear was longer. In that case one wheel will have to go in the trunk.)

(The S5B would definitely be way too soft for track purposes.)

Originally Posted by PST

Very cool event, thanks for the video. Looks like a ton of fun. What camera are you using? (Sorry for all the questions.)

Thanks, btw this year was the 50iest anniversary of that event. It's a GoPro Hero 3.

[MaximeT]

Yes 605mm is great. Unfortunately in Europe there's not a big price difference between Michelin/Yokohama/Avon/Hankook.