I'm going to be running 225/50-15 Vicroracers next season for mostly autocross but I'm sure that 4-5 track days will creep into that. Can anyone tell me what offset I should aim for with the 225 tire? I assume 15x7 would be the way to go, any harm in 15x6.5? What offset would I want with these 40/42? Anyone have specific wheel recommendations? I'm looking for something sub 15lbs but don't want to pay SSR or BBS prices. The Kosei K1 was interesting until I saw that it was a 38et. The AK Tire Monza looks pretty good, does the 15x6.5 really matter compared to 15x7?

Will I have rubbing issues with a 15x.6.5 40et with 225/50 tires? Car isn't lowered, yet.

Cheers,

Paul

 

The 38 ET Kosei will almost certainly rub the fender lip. You need to get a wheel with higher offset to tuck the wheel closer to the suspension, but then you may rub the shocks. Go with a 205/50 15, the tire is narrower (less chance of rub) and shorter (quicker gearing). Kosei makes a 42 ET K1, unless I am mistaken, which happens more often than not. When in doubt call Alex.

 

Kosei makes a 42 ET K1,

Chris is on the $$

Alex

 

A 42 offset for the K1, hrmmm. Am I to take it Alex that I should take all mention of offset on your very informative website with a grain of salt? The 15" seems to only show a 38et. I assume a 42et with the 225/50-15 tires would be the way to go?

Paul

 

Paul:

I ran 225/50/15 BFG g-force TA-KD's on Kosei K1s (38et) last autox season without rubbing issues. Although, it may depend on the specfic tire. I also ran a set of 205/50/15 Falken Azenis on the 15x6.5 Monza AK wheels.

In my opinion the 205/50/15 size is the way to go. We ended up running them almost exclusively in second half of the season. Primarily because the 225/50's higher sidewall gave us more bounce than we were comfortable with.

The 205 size was a better setup.

David

 

>>Paul:
>>
>>I ran 225/50/15 BFG g-force TA-KD's on Kosei K1s (38et) last autox season without rubbing issues. Although, it may depend on the specfic tire. I also ran a set of 205/50/15 Falken Azenis on the 15x6.5 Monza AK wheels.
>>
>>In my opinion the 205/50/15 size is the way to go. We ended up running them almost exclusively in second half of the season. Primarily because the 225/50's higher sidewall gave us more bounce than we were comfortable with.
>>
>>The 205 size was a better setup.
>>
>>David

David, thanks for the heads up. After doing some reading and comparing overall tire size of these two tires I've decided that the 205/50-15 does indeed look like the way to go. Lower sidewall and overall smaller diameter being the main reason. An entire inch smaller than stock should make for a nice gearing effect. The 38et concerns me and Alex hasn't chimmed since his last post to fully confirm the existance of 42et K1s. I've been looking at the Rota Slipstream as well as the Monza that are similar weight to the K1s and are a 40et. I'd prefer a 42 if possible and like the K1's more open design and 7" width a little better than the slipstream and monza.

Cheers,

Paul

 

My 15x7 Kosei K1 are ET 38

Alex