miamirice

Thanks, any experience with the hankook z214?

miamirice

FWIW in this discussion, I stopped in at the shop here that I work with. They track support 10+ Hondas at any given time for purely road race purposes. He said nothing that hasn't been said here regarding rotation but did say on an integra that 225 on a 9" wheel was worked best for them and 205 on a 9" wheel for the EG/EK. He acknowledged some benefits to a 225 front on the civic but said regardless of "what felt good" the 205 was fastest for them.
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Xian

There are way too many variables got a blanket statement like that to hold true across the board. HP and aero drag, effectiveness of the front splitter/airdam, weight of the car, track layout, and ambient conditions will be wildly different. In the SE, 225's are nearly always the fast option for ITA/ITS Honda's... Except at Daytona where 205's can be in the mix unless it's super hot.

What sort of weight is your car (with driver)? Also, how much motor have you got? Any aero work on the front end?

miamirice

Thats why I said "FWIW". I totally agree. His satement was more like "in my hands.......this is what has been fastest" of course running his cars as he has them set up, the only conclusion was 225 for integras, 205 on civics, both on 9" wheel.
I only posted this as this guy has been in the honda game a long time, has raced them all over the spectrum of classes and has helped me a lot. I trust his "been their done that" information. It was by no means a rubber stamp "this is what you must do". Just found it interesting as I weight how to go faster in my car while leaving the motor alone.

If you have run Homestead - I am in the 1;42's on the infield and need to get to the 1;40's to win

My car:

95 EG / K20a2 with bolt ons
Rear Bar and brace
Hard rubber bushings
Ground Control 2812's 950R/650F
camber is assymetrical to run Homestead roval (enduro on bank / sprints on infield)
-2.5 LF / -2.8 RF
-2.2 Rear
Hoosier SM7 205/50/15 or Nitto 01 same size
8" wheel for hoosier / 7" wheel for Nt 01

trail brakes great when on NT 01's
drifts if I run Hoosier front/ Nt 01 rear
does not rotate as much as I would like when all Hoosier

Kiwi splitter/ generic rear diffuser

I need to re-check ride height but I have it a little higher as I am off road pretty regularly at point with the car

Dont know weight of car and it has not been corner balanced

rice_classic

no temp = no good.

If you can't get heat in your rear tires, you will have a car that will leave the track backwards regardless of your setup. They need to be north of 180F to basically *function*. After that however, you cannot abuse them enough, they grip insanely well. I gave up on them though because I got tired of my rear passing my front and the resulting contact with other cars got to be too expensive.

Xian

Understood that it's his feedback but making any statement dependent upon chassis without taking into account engine and the rest of the package seems pretty pointless to me.

With the front splitter/airdam, I've got to think that you'll be pushing most of the air past the front tires so drag shouldn't be a huge deal. With the power/weight of a K20, I'd be looking at 225's at least for the fronts. 245's would be great if you've got the room for them. I'd run 205's on the rear.

miamirice

Oddly enough, the outer dimension data on the company websites make the Hoosier 205/50/15 the same as the toyo 225/45/15....

Xian

Not too surprising really. Hoosier has always made tires that run big (especially so since the RS04, IIRC). They've been able to leverage their tire cantilevered construction to offer a wider tire that still isn't pinched on the wheel.

rice_classic

Hoosier cheater sizing. If I have a open DOT class but limited in size (tire size or wheel size) the Hoosier will have a width advantage.

Toyo has crept into this 'oversizing' with the RR. The 205/50/15 RR is damn near identical in width to a 205/50/15 R6. So in the 205 size, the R6 and the RR are very similar.

But Toyo did not replicate this oversizing with the 225/45/15 RR at least on the same 15x7 wheel. A 225/45/15 R6 on a 15x7 is very wide, but the 225/45/15 RR isn't much wider than a 205/50 RR.

Here's my stack of 205/50 RR next to my stack of 225/45 RR's on 15x7 wheels.: The first pick is the better representation due to perspective.

Dallasb84

Oops ....... Deleted my response as I was to the op from way back

redzcstandardhatch

Dang.... how did I not see this thread a few months ago?!

I recently converted my ITA crx to STL with a 1.5l. . So it Gets to drop 200 lbs from its ITA spec, and its also "basically" an h2 car if I run with NASA.

NASA requiring the Toyo RR led me to buy a set of 205 RR 15" tires....and I'm quite excited to use them. This thread just solidifies my excitement

miamirice

Toyo RR 225/45 15 on 9"





Hoosier SM7 205/50 15 on 8"




My impressions so far is the Toyo RR is less temperamental to being abused but never have the Magic the Hoosier can have for a handful of laps.

rice_classic

Are you saying the SM7 has a "magic lap" because everything I've read says that's a characteristic of the "6" and not the "7".

How do the SM7s hold up after 10/15/20 heat cycles? Performance drop as pronounced and early as the SM6?

miamirice

I have no experience with any "slicks" outside the SM7 and the Toyo. I have now essentially run only 2 sprint weekends after MANY endurance races. So I can only offer my impressions of these 2 tires- same car, same track. The RR felt not much different than a R888. The Hoosier had 3-6 laps that felt like "wow, never felt that much pressure from my race seat bolster before". They certainly don't go the entire 30 minutes but more than just a "magic lap" meaning 1. I have also seen where I race, how everybody it deciding during the race when they will shoot there wad, if early, you have to pray no full course yellow. I think I will try a 225 SM7 on 9" if it won't rub.

Heat cycles- I don't have enough time with them yet. I think I am seeing 8-10 races then rotate them to the back. I destroyed my first set of fronts in 1 weekend from lock ups.

rice_classic

You may need to revisit setup or pressures with the RR. If they feel like R888s then something is definitely wrong. In fact, if any tire feels like an R888 it should be discarded. The RR comes alive after a few cycles but it should feel like an R6 with just a tad more slip angle.