Hey guys, I've been perusing the forum for a while now while I was car shopping and finally got myself into a BO 2007 g35x nav/tech/premium after months of searching for a deal. I have searched and searched, but I still have some specific questions that I can't seem to find an answer for. I don't want to get chewed out for posting multiple threads so I'm going to try to contain this all into one.

First up, I just bought a set of used 20" MRR GT1's which came with two new fk-452 245/35/20's and I'm in the market for a rear set. The wheels are staggered (8.5 and 10) and I have already purchased the Eibach Pro-Kit and rear SPC rear camber arms to avoid the 4x4 look. I see tons of people running 275/30's in the rear with no problems, but really the correct tire to keep everything with the VDC happy is a 285/30 which I would much prefer to run. I found one member here dropped on a Pro-Kit running 285's (lefizzet), but haven't seen many others doing this. I want to know any other people out there are running this size with this drop, and if they had to do any other modifications to make this happen, I'd definitely rather run a wider tire if I can (don't like stretch), but not at the expense of running negative camber outside of ideal factory specs and giving up tire life. The rear offset is 37mm. Another thing that I couldn't find is if we can use OEM lugs with these wheels or if I need tuner lugs, just want to know so I can order them if I need them before I take the stockers off and have to put them back on to make a parts run. I have some time to make up my mind on this, the wheels need some serious reconditioning (deep curb rash) that I'm getting quoted out and I may just do myself, but the sooner I can order what I need the better!

Thanks for any insight you guys can give me, I've picked up quite a bit already just from lurking and countless hours of reading through posts. On a side note, I will get pictures up of my car once I have some decent progress to show for it. I have 2 10w6v2's in a box by customboxman and a jl 1000/1 ready to go in the trunk, and also bought a voucher for tint at our local shop when I can get a day off to bring it in. Once these initial mods are on and I hit it with some 105/205 with my PC I'll be proud to show it off

 

Bump. Did I do something wrong here? I thought it was a pretty well thought out first post, but nobody has any input...any help would be greatly appreciated guys. Thanks....

 

Hey man welcome to the forums. I have been researching wheel specs and tire sizes for over a year now and I just recently ordered a set of forgestar F14s. I ended up on the following specs for mine.

Lowered 1.5" on tien basics coilovers
SPC camber kit front and rear

Front 19x9 +38 245/4019
Rear 19x10 +44 275/35/19

The circumfrence running a 285/35 on the rear would be closest to stock but after looking other posts and searching through the suspension doc on here I decided to play it safe. I ordered my wheels about 7 weeks ago. Typical lead time is 6-8 weeks for forgestars. I will make a post when I get everything set up and dialed in.

As for your wheels judging by other posts I have seen you may end up having to run some negative camber to make the 285 fit in the rear. I would take a look at the database that was built here.

https://g35driver.com/forums/v36-bra...ims-tires.html

Also I used Terry's thread for comparison. He is the only guy I know of on here that had the camber kit and was trying to fit the biggest wheels possible and keep the factory specs.

https://g35driver.com/forums/media-s...007-sedan.html


His specs were here:
Front 20x8.5 +37 245/35/20
Rear 20x10 +48 285/30/20

hope I helped!

 

Thanks for the reply, much appreciated. Glad to see someone was able to squeeze a 285 in the rear while staying in factory specs for camber, I wish I didn't mind stretch as much as i do it would make life easier. Too bad he is running ~10mm more offset than the wheels I picked up are, seems like he is right on the edge so there's just no way I'd be able to make 285/30's work I guess which is sad, I just can't deal with excessive camber wear. Looks like I will be going with 275's in the rear I see that he had to pick up tuner lugs for his, but it seems to be hit or miss as I read through the forums as to whether or not they're needed depending on the rim. I wish I could find a definitive answer from someone with GT1's that tried to fit factory lugs on. I may just buy some and return them if not needed to be safe. Do post pics of your F14's when you get them, they're a sexy rim I wish I had the money to drop on that right now (college sucks). Thanks again!

 

Welcome and congrats on the new ride. I'd suggest trying to use bullets or paragraph breaks to make it easier to see the questions without having to read the whole thing carefully.

I think a 37mm rear offset on a 10" wheel will make it hard to use a 285 tire and keep factory alignment spec without camber. Or you can go with narrower tires to get some stretch if you want to keep alignment spec.

You will need tuner lugs. The factory ones will not work.

I happen to have a pair of used 285/30/20 FK-452s from the rear of my car. PM me if you are interested.

 

Terry, thanks for your reply I was actually just reading your whole thread and your car came out absolutely amazing. I would absolutely take you up on those used FK-452's, but as much as I'm not a fan of stretch and would love some meaty tires I just don't like that bowlegged look you get with lots of negative camber. I guess I will just stick to the 275's and deal with a bit of stretch and maybe buy a new set of wheels next summer with proper offsets to run those 285's. I went through and checked out more pictures today and the stretch on a 10" wheel isn't too outrageous. Thanks for answering my question about the tuner lugs too, is there a recommended set or will any old set off eBay or wherever do the job, after all they are just lug nuts..

 

I'm not sure a 275 will do the trick though. You'd have to do some more research on that.

There are lots of options for tuner lugs in all price ranges. Your local auto parts store will even carry them.

Some will even do a better job than others at deterring theft, but none can actually stop a pro.

Think of them as accents for the wheels.

 

UPDATE: So after speaking with a rep at MRR, turns out I must have made an error in measuring the rear offset as they only offer the 20x10 in 25mm and 43mm offset for this bolt pattern! My method was very crude, and can easily see how I might have made a 6mm error, regardless I am very happy

With this new information at hand, I feel much more comfortable with the room I will have available for a wider tire. From the suspension document it seems like there are a few people running 275/30 with this exact wheel/offset, so I am no longer worried about this as a fallback.

However, as I stated in my first post one member (lefizzet) who also has an X (I don't know if this makes a difference over standard) is running these exact wheels/offsets with 285's, I just wish he were still active so he would answer my PM. Terry, any input with this new knowledge?

Thanks again for all those that have chimed in! I spent four hours yesterday doing curb-rash repair in my garage on two of the wheels. One more with rash to repair then I'm going to ditch the clear/machined lips and polish them up sort of like EnviedG35 did. (on these exact wheels, which I found funny since I decided to do this weeks ago when I got them only to find out a member here had already gone down this road, gotta love enthusiast forums!) Here is a link to the thread if interested: https://g35driver.com/forums/media-s...ished-lip.html

Will post finished pictures when this whole debacle is sorted out! As soon as I iron out this last detail the tires are getting ordered and that's the last thing. Bought locking lugs, new center caps, and hubcentric rings today so we are almost there!

 

From what I was told, your not supposed to run staggered on an X. It could mess with the drivetrain and give you problems in the long run. You should really look into that because i would rather be safe than sorry.

 

Carol, I don't know what that was all about...?

Pwntu, staggered widths is not an issue with an AWD, as long as the circumference is as close to the same as possible it will be okay as there are plenty of fellow x owners who run staggered with no problems. This is another reason I'm wanting to run 285 instead of 245, since its a perfect match whereas 275 is about a 1% difference which is okay..hopefully Terry or someone else can chime back in with some input now knowing the rear offset is actually 43 not 37 as originally thought

 

ttt

 

You have a better chance of clearing now with a 43mm rear offset on a 10" wheel. I had a 48mm offset which means that your tire will poke out only 5mm more assuming you went with a 285 tire and camber is in spec.

Judging by this picture and knowing that the rear fenders are factory rolled, I would guess you can get the 285 tire to work.



Anyone else care to comment?

 

UPDATE: Turns out being an absolute noob with purchasing/sizing aftermarket wheels just totally bit me in the ***. Watched a video on youtube on CORRECTLY measuring offset, and turns out sure enough my wheels are +20 (8.5") front and +25 (10") rear. From what I've found these are the correct offsets for the coupe, but not our sedans.

This is leading me to just hold off on installing my Pro-Kit until after winter because I doubt there is ANY way I'd be able to fit without serious rubbing. Anybody know of any members running wheels of these offsets without a drop? How ridiculous does it look? I just want to get SOMETHING on the car for the next couple months then I can sell them over the winter and that will give me some time to save up/shop for better wheels.

 

I know of on here that had the camber kit and was trying to fit the biggest wheels possible and keep the factory specs.