Question. I'm currently running 265's on a 18x8.5 wheel. I would like these wheels to become DD wheels and another set to be the more "competitive use only" wheels. Seemed like 18x8.5 is the way to go. I'm ok with pulling/rolling the rear fender to fit the wheels/tires. What offset would be best and seems like everyone runs spacers as well(never used them before) so I would be ok with using spacers as well.

 

I have some 265s on 18x10 +38 RPF1s for my street/rain tire. Front needs an 18mm spacer to clear the calipers.

 

Spacers are dependent on wheel design, so it's hard to say. A 265 tire isn't really a factor; it's all about the wheel. Unless you are running some crazy, low offset, you should be fine. I think the OEM wheel is 8.5 or so...? There should be no pulling needed, though rolling may be a good idea with that tire width. I had a 9" wheel on a IX that was a +30 and it seemed to fit really well. No rubbing, looked nice, etc. If I was looking for "herra frush", then I probably could have gone a bit lower with the offset. an 8.5" with about a +24 or so to set in the same place.
There is an extensive wheel fitment thread. Have you searched it? It's kinda long and hard to find specific sizes.. but worth a shot.
Out of curiosity, why such a wide tire on the narrow wheel?

 

8 inches is oem wheel size for evo 8-9 I believe. Mine came with aftermarket 8.5 works wheels. I went with bigger size because wider tire means more grip, right? I've asked people and most seemed to say wider tire is better, was very controversial lol.

I've browsed through the wheel fitment thread but I guess I was am just looking for more info from experienced people on wheel fitment that actually run on track/autocross courses. Also i somewhat read having a wider track can be helpful. I haven't researched much about it but just making sure if I buy something once I buy the right stuff and not regretting it later.

 

As wide of a tire as possible, on any given wheel, is better for drag racing and AutoX, where the need for overall grip outweighs pretty much anything else. If that's what you are doing, then you are good to go! I've never competed with an 8.5 wheel, so have never tried to fit one. Hopefully someone can chime in. As for a wider track: theoretically, I suppose. But there's a lot more to factor in. Definitely not a good reason to sun a spacer. Those should be used to get wheel clearance from your brakes, if needed.

 

The evo just happens to need a different offset front and rear when you really start pushing the tire size and then its also dependent on the camber you run. I use to run a 20mm spacer for 285s but now with less camber only run a 17mm spacer. It wouldnt be possible to fit the 285s with any amount of camber next to the spring without a spacer. Maybe the strut if you are able to run a short enough spring getting the perch above the tire though.

But yes, its becoming apparent to me that more tire is inevitable. Cant fight physics though, even 285s isnt enough when trying to manage 900lbs/tire. Just watching the difference in cornering speed between a big tire car at nats and small, it was pretty visible how much more cornering force the big tires had.

 

How much tire do you think you can stuff under mutilated stock fenders?

Or are you just going to ditch the stock fenders and go all out?

 

295s is the most Ive been able to get under stock fenders. Im limited on the inside rear by the strut unless I shift that inward dropping MR also. I could make some rear lower arms to relocate things inward a bit but thats not something Im looking to change. So now the next step is to just cut the fenders. Im not sure how much I'll be able to cut in the rear but I think I have lots of room up front once I pull the fender and relocated the harness. I'll just be pushing to get the front as low as possible and still steer. Rear will probably be limited by how much Im willing to cut but Im ok with that running higher.

 

ive had 9.5 +12 rims with a 245 tire on stock front fenders with a spacer in the back where it bolts up. the rear needed a good pulling tho and decent camber etc to get in the guard and still rubbed occasionally.

8" is stock rim size btw for 7 - 9.

In general a wider tyre means more grip. but it needs to be matched to the right size rim also otherwise if the tyre is too big for the rim the sidewall will roll around and be too soft. the opposite is a tyre too small for a rim where the sidewall has no flex and movement and you get no grip. Pro drifters have just recently begun oversizing their tyres to their rims because it gives them more lateral grip in a slide due to the way the sidewall can flex around.

The bigger the tyre the more grip. but also the more weight u carry. the more surface area u have to heat up. and increasing track width can make the car understeer more. So you can go too big.

I run a 280 wide slick on a 500kw dedicated GT circuit car and i wouldnt dream of going any bigger. i actually downsized to a 265 for my rain tyre.

If ur looking at like a 265 tire find out what rim size is recommended for it and hang around that size. the manufacturer will have a recommended rim size. id imagine its somewhere around 9"

Then offset etc is up to you how much u want to modify ur guards and what design wheel you get and what not but u shud be able to get most 9" wheels in without much hastle. If you can get a wheel that fits in the guard and doesnt rub on the brake n spring without spacers thats ideal. if you have to run small spacers than do it but obviously not the first option. The guys i race with say ideally you want to stay as neutral offset as you can. but in reality i doubt your going to have a very big window to choose from with a 265 tire on it so it is going to come down more to what fits over whats ideal for handling.

 

Dallas what is your plan for that wire harness up front? Plan to move it inside and drill a hole through the firewall or just tuck it up higher?

 

I need to look at it again, but I thought I might be able to cut the harness and reroute it through the square section of frame rail above the tire. Might have things wrong in my head though. That harness definitely has to move though.

 

Through as in inside it? Id have to look again but Im pretty sure it necks down inside the rail to like an oval shape at one point so squeezing the harness through it might be tricky. Also wonder what happens when it gets to the actual firewall? That harness is a concern of mine too; I do not want to rub through that but currently its still sitting there fine. I thought about just pulling it up as far as I can but in current form there is no contact. Once I get your uprights I'd like the get the front end down more and that may pose to be an issue.

Now, Im not as creative as you however at some point if you youre going to be limited by inner frame rail and wheel well which means your options are less steering angle or move the wheel outward and cut space or leverage over fenders. I just barely rub at full lock which means to go to say a 12" wheel and 335s I need another 1.5" of outboard clearance.

 

Yeah, 315s are 1" more outward clearance and 0.8" taller. So I fully expect these guys are going to be fun to fit with the car low. My current plan is to run the EvoX control arms Im working on which will be 15mm wider than Evo8/9 arms to get less scrub and swing on the tire. Then with however low I can get it, push the wheel forward to clear the inner fender well.

I assume I'll be doing a little more trimming or hammering in the fender well and probably have to do something with the side skirt too. But being able to push the wheel forward and cut the bumper is going to be a nice perk for clearance as it was on the 295s.

 

i removed the silly plastic shrouds from mine. a bit of tugging and pulling and i used a couple of the existing holes in the box section and cable tied the loom up on the side of the rail as such away from the tire so it would hit the box section before it would hit the loom. Was having issues during long high speed corners with the car leaning over and rubbing through the box section before.

Ideally youd want to remove it completely. i looked at putting it inside the box section but youd need to cut and splice the whole loom.

 

Yeah I think that right there is the reality. Cutting up the bumper and lip is far simplier than dealing with stuff by the side skirt area. I trimmer a little bit around my side skirt to make room but if my front end were lower it would be much more difficult to make them fit. Getting those wires into the frame rail would be cool but I dont love the idea of snipping it to do so. Im not sure if extensions would be needed but would be cool, although a ton of work to depin it at the fuse box to snake them through. Realistically pulling it up as high as possible might be fine.

The other thing and Im stating the obvious is that there is only so much cutting and hammering that can be done until you run into physical obstructions that you just cant get past. For example driveside inner fenderwell you have frame rails that really arent going to be moved. But even if you were able to do something with that the you will quickly run right into the transmission case. My point is eventually you reach a wall and the only place to go is outward. But Im very excited to see what you come up with as I plan to follow suit.