17x8 Enkei RPF1, what offset?

[Zmann42087]

I'm thinking about getting some 17x8 Enkei RPF1's for track wheels. I was checking out sizing on tire rack's website, and it shows a +45 offset with a 215/45/17 tire for my car. Thats not what I had in mind. I was thinking of running a lower offset and definitely a wider tire. IIRC, I talked to a guy on here who had 17x8 +35 RPF1's on his car. So I know anywhere from a +35 to +45 offset will work, but I guess I'd like to know what offset in that range is ideal. Keep in mind, I'm FWD and decreasing the offset increases the scrub radius which will increase torque steer. Its a necessary evil if I want to run wider rubber, but I want to find the best compromise between the two.

 

[tsidrift1]

Looking for new rims too!? Have you seen the thread with the 1g that fits the 17x9 with a 45offset? You need to run some 9's man. I am looking to get at least nines hopefully all the way around. Just cant seem to find any with the right offset. I would think a 40et would set those wheels just right. Im not sure if they make them in a 40 though.


Anthony

 

[D_Eclipse9916]

17x9 +40 is perfect on a 2g.

 

[eclipsegsx1736]

I'm not sure what offsets are available in a 17x8, but as said above a +40 is ideal for a 17x8 on a 2g. You should probably run a 235/45-17 tire which is readily available. Another nice advantage to that size is that you can buy Advan A046 tires from Evo guys, they often sell theirs used and they are some of the best street/track tires you can buy for the money. Plus they work well past the point where they're bald.

For a 17x9, +35 is closer to ideal on a 2g so that you can take advantage of the wheel width and run a 255.

 

[tsidrift1]

I wish the options were more open for 1gs running a wide wheel without sticking out too much.

Anthony

 

[Zmann42087]

17x9 +40 might fit, but I'm guessing I'd have to run a stretched tire to make it work. That'd kinda defeat the purpose if they're going to be my track wheels. As mentioned, I need something more like +35 if I want to get some appropriately sized rubber on there. But then the wheels would stick out past the fender wells and I'd rub like crazy. Beau gets away with it because he doesn't over lower his car like most people do. Just another reason why I need coilovers.

So yeah, I'm pretty set on 17x8.. my only concern was the offset. I'll probably give tire rack a call tomorrow and see if they carry them in +40. Thanks for the help guys!

 

[DSMSpyder99]

8" wheels are so 2006...get 17x8.5 40mm offset and 245/40/17

 

[D_Eclipse9916]

245s on 38 offset with a ton of room, I would think plenty enough for 255 at 40 offset.

 

[DSMSpyder99]

Tire width really depends on manufacturer.My old 245 Michelin Pilot Sport were BARELY wider than my 225 BFGoodrich G-Force Sport on my old 8" wheels. Tires such as RT615, Advan Neovas, Direzza Z1, Nitto NT01, and RE01R run extremely wide for their width.

 

[Ludachris]

If you're doing track-only wheels, you're likely going to go with at least an R compound tire (otherwise you're defeating the purpose of getting track-only wheels). I'd say an 8.5" or 9" wide would be the best bet along with a 235-255/40 tire. A stretched 235 on a 9" isn't a bad thing really. In fact, a guy who races in World Challenge suggested I run that instead of the 255 on a 9. It certainly wouldn't handle any worse than a 235 on an 8, plus it will give you the option of going wider if you wanted to later.

The difference in weight on the RPF-01 between an 8" and 9" wheel is only a couple pounds, if that, and the price is similar. It's worth having more options, especially if you want to be competitive in the future, which many people eventually do. Our cars tend to be at a disadvantage in many rulebooks, so having as much contact patch as you possibly can ends up being extremely important.

Don't waste money by purchasing the wheels that you think you'll be happy with now, only to find you want wider in the future - it's a common mistake in the DSM world. I've made it myself. Always plan ahead and just assume you're going to want to compete later. It'll save you time, money, and headaches.

 

[Zmann42087]

I had a couple reasons in mind for running dedicated track wheels. I want to go down an inch in wheel diameter, add a little bit more track width, and definitely reduce unsprung weight. But you're right, most importantly I'd like to run some stickier rubber. I've narrowed my choices down to shaved Bridgestone Potenza RE-01R tires or the BFGoodrich g-force R1. Both are about the same price for a given size.

I'll probably reconsider my decision on the wheel width. If this many people think I'm making a mistake, I probably am. I was worried about fitment/rubbing issues because the Tein springs I have now are too low and under sprung, but (hopefully) I'll have Megan coilovers by next season anyways. Plus, I know I'll be dialing in more camber for track/autocross days and that'll help the wheels clear the fenders.

 

[Ludachris]

I had a couple reasons in mind for running dedicated track wheels. I want to go down an inch in wheel diameter, add a little bit more track width, and definitely reduce unsprung weight. But you're right, most importantly I'd like to run some stickier rubber. I've narrowed my choices down to shaved Bridgestone Potenza RE-01R tires or the BFGoodrich g-force R1. Both are about the same price for a given size.

I'll probably reconsider my decision on the wheel width. If this many people think I'm making a mistake, I probably am. I was worried about fitment/rubbing issues because the Tein springs I have now are too low and under sprung, but (hopefully) I'll have Megan coilovers by next season anyways. Plus, I know I'll be dialing in more camber for track/autocross days and that'll help the wheels clear the fenders.

The RE-01R appears to be a high performance street tire. No real point in going with a street tire on track wheels. The BFG R1 looks like a good choice. How much research have you done in the road racing/autocross arena on them? When I was doing research I found that the two best/low cost tires on the market were the Toyo RA1 and the Nitto NT01. They had the best wear characteristics, with many people using them for a whole season or more. And for being a long-lasting tire, they were pretty sticky and had great response.

I currently have the RA1's on my car and am pretty happy with them. I'll be trying the NT01 next though. How do the BFG R1's compare to these in your research?

 

[eclipsegsx1736]

The BFG R1 and the Bridgestone RE01R are pretty outdated as far as performance tires go. Like Chris said, the RA1 (or NT01, which is the same tire compound just different design) are a much better track tire choice for cheaper. If you wanted more of an aggressive street tire that can also be tracked, the Dunlop Direzza Z1 Star Spec is cheaper and better than the RE01R.

 

[Zmann42087]

I know both the NT01 and RA1 are great choices when it comes to track day rubber, but Tire Rack carries neither Nitto or Toyo tires so thats why I wasn't considering them as much.

The Bridgestone RE-01R I was considering because I've seen guys run it with great success in auto-x. I know its not a true r-compound, but it would work well for me and wouldn't bump me up a class. On the other hand, I'm hoping to do more track days and less autocross next year so thats why I was considering the BF Goodrich R1. Honestly, this is the one I'm leaning more towards right now.

Really though, you think the BFG R1 is outdated? It only came out last summer and I know the NT01 has been out at least two years, maybe more. I'm not saying that makes them better tires, but they can't be that outdated. So far, I've read a couple reviews.. I found one "preview" by tire rack back when they came out last year. They compared them to Hoosiers and it sounds like they're similar in terms of grip. Here is the preview in case anyone wants to read it... BFGoodrich g-Force R1 Preview Track Test. I found one other good review here too.. Trackpedia Forum - BF Goodrich R1 Tire Review. Watch the video review if you want, but it looks suspiciously like a BFG promo video or something, so take it with a grain of salt. More interesting in that second link is the review by "TailWagger". I like it better because its coming from someone with a neutral perspective. Its sometime hard to wade through all the biased BS on the web. That review has none of it. Anyway, its coming from a guy who had run Toyo RA1's for three years and it sounds like the BFG R1's compared nicely. According to his logs, his was pulling 1.3 g's (max lateral grip) with both tires, but the BFG R1's netted slightly quicker lap times.

 

[Ludachris]

I know both the NT01 and RA1 are great choices when it comes to track day rubber, but Tire Rack carries neither Nitto or Toyo tires so thats why I wasn't considering them as much.

The Bridgestone RE-01R I was considering because I've seen guys run it with great success in auto-x. I know its not a true r-compound, but it would work well for me and wouldn't bump me up a class. On the other hand, I'm hoping to do more track days and less autocross next year so thats why I was considering the BF Goodrich R1. Honestly, this is the one I'm leaning more towards right now.

Really though, you think the BFG R1 is outdated? It only came out last summer and I know the NT01 has been out at least two years, maybe more. I'm not saying that makes them better tires, but they can't be that outdated. So far, I've read a couple reviews.. I found one "preview" by tire rack back when they came out last year. They compared them to Hoosiers and it sounds like they're similar in terms of grip. Here is the preview in case anyone wants to read it... BFGoodrich g-Force R1 Preview Track Test. I found one other good review here too.. Trackpedia Forum - BF Goodrich R1 Tire Review. Watch the video review if you want, but it looks suspiciously like a BFG promo video or something, so take it with a grain of salt. More interesting in that second link is the review by "TailWagger". I like it better because its coming from someone with a neutral perspective. Its sometime hard to wade through all the biased BS on the web. That review has none of it. Anyway, its coming from a guy who had run Toyo RA1's for three years and it sounds like the BFG R1's compared nicely. According to his logs, his was pulling 1.3 g's (max lateral grip) with both tires, but the BFG R1's netted slightly quicker lap times.

Don't limit yourself to what is sold on TireRack. It's nice to see you're looking for feedback, but look around your local area for deals - our local NASA group works with a local vendor to get good prices on RA1's. You can probably find a similar situation in your area through NASA or SCCA (or similar road racing/autocrossing groups). If not, you can find a couple vendors online that have decent prices. PM me and I'll send you a link or two.

I'm not saying the R1 is a bad choice, just that I've found the NT01 and RA1 to be the better choice from more people so far. You're going to have to make your own comparisons though.