Looking to see what exact size rims and tires fit at max on a stock 93 r1 suspension car with rolled fenders ! Width offered on time are 9.5 and 10.5, both 18s, looking to run same size all the way around to be able to rotate correctly, but at the same time want to put down maximum tread width. Would prefer tallest sidewalls aswell. Yes I am a noob but there is information overload, and havent found anything on a rotatable 18" setup. Thanks guys !

 

You want to rotate 9.5 and 10.5 inch wheels? Even if you are using the same tread width, the contact patch will be a different shape and size between the two wheels. You will need to run a square (same width front and rear) set-up.

There is a guy (abc) running 315 tread width in the rear (with aftermarket trailing arms) with stock fenders (rolled only). The rear fitment will be no issue if you are rotating, you will need to worry about the fronts.

You say tallest sidewalls possible, so I am assuming you do not want to stretch the tires...? Stock tire height is 24.85", so with 18" wheels you are looking at 6.85" of sidewall total to maintain speedometer reading. 255/35, 275/30, 285/30, 295/30 will all be close. 265/30 would probably be ok too, but will read low. The speedometer itself can be recalibrated, so this may be a moot point. 275/30 is starting to get adventurous in the front (IMO), but should fit with reasonable camber (talking 1.2*) and the right offset (I'm guessing low-mid 40s). I had a square 17x10+50 setup for a while, with rolled fenders. Only rubbing I ever had was on the shocks themselves (stock touring), which is why I suggest a slightly lower offset than is normally suggested. Definitely had a lot more space to push the wheels out (I can't complain, though, they were cheap, used CCW's). I was running -1.2* camber all around, btw. I'm thinking 18x10 +40 with 275/30 or something like that would be perfectly fine with rolled fenders. Wait for some more replies before buying, though. Another alternative is to go through this thread: https://www.rx7club.com/suspension-w...itment-895289/ and see if you find something you like.

How much camber are you planning to run? Any plans for coilovers (or at least lowering the height) in the future? What kind of tires do you want to run? Purposes with the car?

There is not too much info, just not enough understanding.

 

Sorry I didn't include more information. I'm getting custom wheels so I can get whatever offsets I need, but they offer the wheel I want in two different widths to choose from, a 9.5, and a 10.5, I'd like to run the wider rim as it features a more concave look. So if I did get the 18x10.5s, what would the required offset be to run them all the same, and what tire size for that matter? I need tires and new wheels really bad so I'm doing it first before my suspension. I would like to do a coilover setup in the future, but for now I am probably gonna stick with the R1 suspension and maybe around christmas or new years ill throww a set of drop springs on it. I don't want the car too low, and with the stiff r1 suspension I dont really scrap too bad or in too many places.

 

It's gonna get daily driven a lot, will probably see its fareshare of rain and wet weather driving. I was wanting to put the widest michelins on it I could and still rotate properly.

 

From what I have read, the max I have seen being run up front with stock rolled (not pulled) fenders is a 285 - no, I do not have a specific post to refer to, alignment specs, or wheel specs. With a 10.5, I'm sure you could get away with a 265 up front without looking stretched (much, if any). I cannot find any sources, but I think that is within the acceptable range of widths for most tire companies. 275/30 would be closer to stock height, but clearance is getting tighter.

The reason I ask about coilovers is because they typically (or at least, the ones I can remember - please correct me if I am wrong) have a smaller diameter body than the stock shocks - so you have more clearance. My problem with 17x10+50 was rubbing the shock body (and ever so slightly rubbing the liner at max angle, over speedbumps and such). If you upgrade to coilovers (good ones, not cheap megan racing or bc racing crap) or even Koni yellows or something, you can get adjustable bump damping with better valving than the stock shocks. So, to greatly simplify, more comfortable around town, better grip when it matters. And, you will have more clearance.

I had some spare room between tire and fender with my 17x10 +50... but it was maybe a quarter inch (possibly more). Let's assume it's a half inch clearance that I had. To close this gap with a 10.5" wheel, you would need +45 offset at least, depending on camber. This puts the inside of the wheel exactly where my setup used to be. But the rear would be safe - would probably look "sunk" to a few people here. Might necessitate purchase of aftermarket offset trailing arms, but those with more experience should comment on that.

Still need more info. How much camber do you want to run?

I think you'll have less headache with the 9.5

 

With a 18x10 up front and a +50 offset I am right at the limit of sticking out of the fender. On the inside of the wheel I am a hair away from rubbing on the lower A-arm at full lock. Also note I have aftermarket coil overs. I HIGHLY suggest not running more that a 9.5" wide in the front on stock suspension. Unless you are using wider fenders and a lower offset. Ideally I would find the 9 or 9.5 to be the best fit up front. In the back a 10.5 will fit with a massive 315/30 tire with nothing more than a rolled lip and aftermarket trailing arms and stock camber. Have to be careful with the choice of tire though.

Also note that Michelins run wider than Falkens or Kuhmos so a 295 or 305 will have to be used in the back. In the front I suggest less than a 285. I get a lot of tracking with them but not at all on my 255 tires.

I also wish I had gone staggered. A 9 or 9.5 in the front and a 10.5 in the rear. Being able to rotate the tires is nice enough but I'd prefer the traction and no road tracking over the rotation.

In the end I think that if you want wet traction, stock camber with the 9.5's all round is better(+50f/+38r). The 285/30-18 Michelin PS2's would make a great combo.

 

^ good points. Honestly, I went with 18x9.5 and 18x10.5 with my wheels for all of the same reasons. He wants the 10.5 because of the concave face and to rotate wheels, so I was trying to work around that. I'm sure a 10.5 would fit under stock front fenders if you really really want them too..... As in camber and tire stretch.

If you want to run 9.5 all around and still rotate, offsets in the mid 40s would be ok for all 4. +50 up front is a little conservative, imo. 285/30 is the closest you will get to stock tire height, so that's a good choice.

 

I went with 18x10.5 +38 all around as I could not find a wide monoblock with higher offset in stock anywhere.

This low offset limits me to 265/35-18 with front fenders rolled and stock rear. I auto-x and street drive. I have front camber maxed at -2.4 deg and rear is -2 deg. Could use more for auto-x and less for the street. I have the least tire wear in the center of the tire and I run 38psi hot.

If you can get an ideal 45 offset the same 18x10.5 will support 285/30-18 all around with just the front fenders rolled.

I am considering getting Forgeline F14 in 18x11 +45 or using the rims I have with offset front upper control arm bushings for more camber and rolling the rear so I can run 295/30-19 R888 all around as they are cheapest in that size (compared to 265 or 285).

 

Hey guys, once again let me thank you for putting up with only the x3,453,948,574 thread started about FD wheel fitments, and thank you for taking your time to reply with your knowledge and specs. Its been many months since I first created this thread, and due to financial means, medical issues, and still having my FD apart, wheels have kinda taken a backseat to things. I am getting closer and closer to finishing the new motor install on the car and the GT40R swap I did, along with countless other mods and looking towards running a safe conservative daily tune right about 400-450hp to the back tire. I have been learning more and more about wheels and fitments for the car in my spare time, so hopefully you guys can help me get ready to order as I intend on getting the wheels shipped within the next 2 weeks. Just an update to a few things already mentioned. The wheels I am looking to run are 18x10.5 and I am really looking to run them all the way around to be able to rotate properly as I am not looking to burn through tires at all, and with as much rain as we get in the summer here my main concern after wheel size is wet weather traction. I have learned a lot about the car having tracking issues after going up to such a large width in the front, and I do see a possibility of stepping down in width to avoid this issue, but I am still ignorant as to how the tracking issue fully effects your line. top speed, etc when in time attack mode. I still see width as grip and grip as in a quicker time. For the time being, I am doing things in a rather backwards mode, as I have tackled all of my reliability issues, engine performance etc first. My suspension I already believe will be lacking, but I am limited. I am running a completely stock R1 Suspension, and I am looking to try to hold onto it, and possibly do some Super Down Blue Springs closer to winter. If in the end this object is just not reasonable to maintain in order to purchase the most effective width / offset / etc I will probably switch out to a set of stockers intill I can afford to do the upgrades more effectively. My main goal with this car, is mostly Friday-Sunday car, with the few days driven to work when I cannot say no, and to show it, auto-x occasionaly. Back to the wheels tho, they have been backordered for some time, and the only wheels I can get myhands on anytime remotely near this summer, are 18x10.5 +30. What will be the max width I can run on this setup front and rear both a) rotatable & b) staggered? If the proper offset is going to be +45 would it be ignorant to run a 15mm spacer kit to achieve this? Thanks guys, and hopefully you will be getting to see more of my FD soon.

 

Hey guys, once again let me thank you for putting up with only the x3,453,948,574 thread started about FD wheel fitments, and thank you for taking your time to reply with your knowledge and specs.
Its been many months since I first created this thread, and due to financial means, medical issues, and still having my FD apart, wheels have kinda taken a backseat to things

I am getting closer and closer to finishing the new motor install on the car and the GT40R swap I did, along with countless other mods and looking towards running a safe conservative daily tune right about 400-450hp to the back tire. I have been learning more and more about wheels and fitments for the car in my spare time, so hopefully you guys can help me get ready to order as I intend on getting the wheels shipped within the next 2 weeks.

Just an update to a few things already mentioned. The wheels I am looking to run are 18x10.5 and I am really looking to run them all the way around to be able to rotate properly as I am not looking to burn through tires at all.

With as much rain as we get in the summer here my main concern after wheel size is wet weather traction. I have learned a lot about the car having tracking issues after going up to such a large width in the front, and I do see a possibility of stepping down in width to avoid this issue, but I am still ignorant as to how the tracking issue fully effects your line. top speed, etc when in time attack mode. I still see width as grip and grip as in a quicker time.

For the time being, I am doing things in a rather backwards mode, as I have tackled all of my reliability issues, engine performance etc first

My suspension I already believe will be lacking, but I am limited. I am running a completely stock R1 Suspension, and I am looking to try to hold onto it, and possibly do some Super Down Blue Springs closer to winter. If in the end this object is just not reasonable to maintain in order to purchase the most effective width / offset / etc I will probably switch out to a set of stockers until I can afford to do the upgrades more effectively

My main goal with this car, is mostly Friday-Sunday car, with the few days driven to work when I cannot say no, and to show it, auto-x occasionally.

Back to the wheels tho, they have been backordered for some time, and the only wheels I can get myhands on anytime remotely near this summer, are 18x10.5 +30. What will be the max width I can run on this setup front and rear both a) rotatable & b) staggered?

If the proper offset is going to be +45 would it be ignorant to run a 15mm spacer kit to achieve this? Thanks guys, and hopefully you will be getting to see more of my FD soon.


Ok, I quoted your text in a little easier to read format. I will address what I saw as the relevant points.

You will be driving a GT40R powered FD RX-7 somewhat regularly on the street, to car shows and perhaps an occasional autocross.
You want max traction, but are also worried about wet traction as it rains a lot and if possible you would like to keep your stock suspension.

Traction concerns-
The big turbo will actually make it easier to accelerate in the rain when you are driving easy on the street as there won't be boost (torque) until higher RPM. Sequential twins (or a V8) are really the hardest for this as there is torque even at low rpm and with minimal throttle input.
Wider tires really do make hydroplaning in standing water happen at a much lower speed. I found that out on a roadtrip in my FD. It was scary coming into Portland in a torrential downpour with the ruts from trucks pulling me into their deeper water and then sending me hydroplaning into the next lane. You can counter this to some degree with a tire that has excellent water evacuation.

This is a problem with standing water. From what you write I don't think you would choose to drive your car through storms and if you got caught out in a freak storm that dumps standing water you could drive slowly and carefully to your destination.
I have found wide max performance summer and race tires work well enough with warm wet roads.
A tire like Toyo R1R would work excellent on dry roads, wet roads and even into cooler temperatures (not snow by any means) even in wider sizes and are excellent for autocross. They have a very soft compound that works best at low temperatures, so going quite wide on a lighter car will work well with these tires.

Rim and tire width-
If you really want to keep your stock shocks you will be more limited on rim and tire width. I can't advise you on max width with stock shocks as I have coilovers.

If you go to coilovers an excellent new wheel choice is the Enkei PF01 (as I had in the above photos) are now available in 18x10.5 +47 offset. This will allow you to run a 265 to 295mm wide tire depending on whether you roll your fenders and how much camber you run. It is the widest "off the shelf" fitment with the closest to ideal (for fitting tires) +45 offset I have heard of so far.
In the above photos I had the PF01 in 18x10.5 +38 and the lower than ideal offset limited me to 265mm wide tires with front fenders rolled and stock rear fenders with some camber.

If you added 15mm spacers to a +30 offset you would then have an effective +15 offset- you were thinking of it backwards.

With +30 offset you are limited to 255 width tire with a roll in front and the rear will fit without a roll if you have some camber or a roll without camber.

I did order 18x11 +45 Forgestars and though they took 4 months to be made it was worth it to me and they fit the 295/30-18 with stock rolled fenders very well.

 

Oh, you mentioned tracking issues with wide tires- which I did not address in the above post.

Wider wheels and tires will tend to track into grooves in the road more easily for the simple fact that some part of the tire is more likely to be in the groove to start with.

It is really deviating from the stock 50mm offset that causes most of the tracking/wandering issues that most people will complain of with "wide" wheels. The further from the stock +50 on the FD the worse the tracking issues.

You will feel this as pulling into grooves on the freeway, pulling side to side when braking hard and more pronounced pulling to one side with the vehicle straddling road crown.

The further from +50 offset the more steering effort you will have as well. (not always a bad thing on the overboosted PS the FD has).

I found my 18x11 +45 with 295 exhibit much less wandering, pulling, trammeling behavior than my 18x10.5 +38 265 fitment and had noticeably easier steering effort. This was with the same tire model even and both new (just different sizes).

This phenomenon is a result of moving the center of the contact patch away from the axis of steering.

 

A spacer will take you from say a +50 to +35 not the other way around. That would require machining the mating surface of the wheel or changing barrels on a 3-piece. It's ALWAYS better to go with a little too high of an offset as you can add a spacer if you need too. Too low and you risk HAVING to pull the fenders or get wide body fenders(stretched tires increase flexibility). A 10.5 + 30 is really pushing it for the front.

My CCW's total width is 11" despite them being marketed at 10". The bead seam is about 10.5" With a +45 (50 with 5mm spacer) rear I have room to spare with narrow 285 sumitomos and no rolled lip. The front with +50, no spacer, same tire, I had to roll the lip and I get a very little rubbing on the lower arm from the inner lip. I'd say that +50 10.5(aftermarket suspension) is the 100% max wheel in the front without new fenders.

I am now opposed to running an all round setup. In order to get the most traction out of the rear and minimize tracking issues you need a narrower tire in the front. My 285's keep you alert to say the least with them in the front. My 255's have zero issues. If you plan on running a 300 series tire the wear rate won't be that big of an issue. My only issue is that the rears wear faster due to ummmm the wheels spinning faster than the ground is moving. I have now had those tire for four years. Still have plenty of life left in them.

My next time around I'll be running 10.5-11 ~+40 rear and a 9"+50-9.5"+45 front. 255/265 front 295 rear.

A stock R1 suspension limits you on the inside. I have JIC coilovers and aftermarket trailing arms.

For a completely stock suspension and body I'd say 9"+45 to +50 front, 10"+42 to +45 rear.

I used to have a set of 18x9.5 +38 on a 275/35-18 tire and the outside rubbed in the rear with plenty of clearance inside. Stock everything. The front rubbed the fender.

Tracking will be an issue with 285+ front tires. If you run a stickier tire a 255/265 can handle the braking just fine. My 255 tires are 180 tread wear and grip great when warm.

Sorry for the bit of rambling. I'm sure others will have some input but this is what I have found works on my car. I also run my alignment within mazda specs. The only thing I change is the rear camber for the 18x10 285's. I run around -.5* and -1* on the 17x8 255's.

You may want to consider 17's. They ride better than the 18's and give great forward grip. You may loose a little in the corners but hardly noticeable. Most CCW centers are 17" including the classics. The simply do a 1/2" step in the barrels to get 18". My SP500's are like this.

Blue TII what tires are those. I don't recognize the tread.

EDIT: for the front I'd keep overall diameter under 25". Rear should be okay under 26". (drag tire) But I'd prefer under 25.2"

 

My CCW's total width is 11" despite them being marketed at 10"

Sounds normal. My 18x11 +45 Forgelines measure exactly 12" wide.

Blue TII what tires are those. I don't recognize the tread.

Hankook Ventus TD Z221 295/30-18 C70 compound.


My 285's keep you alert to say the least with them in the front

To my surprise I didn't find this at all with my set up. I enjoy driving it on the street so much now I have some 295 Toyo R888 on the way so I can drive on the street without heat cycling the tires out. It feels rock solid.

 

Strange. Makes me wonder if it is the tires. The offset on the CCW's is +50.5 with 285 Sumitomo HTR Z III's. My 17x8's sit around +37 I think with 255 Kuhmo Ecsta XS. No bump steer or tracking with those.

 

I am sure tires will make a difference. Wow, tiny tread blocks that are 10/32" tall new on those HTR Z III- thats wobbly!

What kind of tire pressures are you running? I would try 42-44psi in front and 39-41 psi rear hot (after driving). 50PSI max pressure on those I believe.

I had some Hankook RS-3 that felt pretty gross till I aired them way up.

 

I usually have them around 30psi cold. I had them a little higher, around 33, and after a while I noticed the center was wearing a little faster so I brought it back down.

They do have a lot of small shapes but they don't feel that bad in the corners. Just straight line stickiness isn't there at all. They weren't that cheap when I bought them either. They must be replacing them soon.