Ok I have some tire size questions.

allnotch · 07-03-2008, 11:25 AM

I have a 02 gt with 9inch rims up front with 235-45-17 and 10.5 out back with 275-40-17, the rims are cobra r replicas and how wide can I go in the back? I noticed that there are shocks right there by the tire wall , just looking for a wider tire and wondering which size I need.

Jazzer The Cat · 07-03-2008, 07:00 PM

'Holy re-post, Batman..... I just answered this question yesterday!'

You can go 315's out back so long as the off-set is correct. I figure a 275 must look pretty stretched on a 10.5' wheel [&:].

I recommend you park your car at an angle on the bottom of a steep driveway and heavily articulate the rear axle (if one end is on the bump stop, that is best) Do some measuring on all clearances around tire and fender, exhaust, shocks and such on BOTH sides of car. You will see how much wider you can go. I am currently running 10.5' Saleen replicas with 1/2' spacers and extra-long andheavy lug-boltsrunning 295's. Am going 11' rim with 315's next week.

You can look ***HERE*** for an earlier thread and can see some pics as far as how they may look.

Jazzer

allnotch · 07-03-2008, 10:23 PM

It really dont look stretched at all, but I will measure 2-morrow and post on here what I'm looking at. It already had these on here when I got the car so the back spacing I'm not sure.

allnotch · 07-04-2008, 01:25 PM

Ok here is what I got, 3 inches from the front of the tire and the rear of the tire, 4 inches from the top of the tire to the top of the quarter panel, 1 1/4 from the exaust and 1 1/4 from the shock, so what can I get on there? Where does the sizes go upfrom 275-40?

Jazzer The Cat · 07-04-2008, 02:56 PM

My '02 Saleen has 10.5' replicaswith aback-space of exactly 6 7/8'. I am currently running 1/2' spacers on them and still have over 1/2' clearance on the inside of tire to all obstructions. I have ordered a second set of the identical wheels for Summer tires andhad them widened to 11'. I will install a set of 315's and have basically zero clearance on the inside, and will more than likey have to take a hammer to some parts of inner-fender behind the wheels.

OneBIG difference from my car and yours. I am running a full Griggs GR-40 suspension and the rear axle articulates differently than yours (no upper control arms.Replaced bypan-hard bar and torque arm). I have a little more clearance due to this suspension and don't recommend 11's on your car.

If you get 10.5' wheels with a 6 7/8' back-space, you will fit fine. You may have to roll your fenders a little (not hard, butshould be done by a paint/body shop). You may also need to do a little 'persuation' to inner fender wall behind tire (will not be visible unless tire is removed from car). If you rub on the inside, you may consider longer lug-bolts and spacers. I originally added the spacers to bring the wheel to the edge of fender for appearance. In doing so, I gained the 1/2' space in back, so going to an 11' rim

You will also want to stay with 35 series on 17' rim or 30 series on an 18' rim if you go 315's.

Jazzer

allnotch · 07-05-2008, 12:50 PM

Jazzer I followed your link above and could not see the photo bucket pics but I seen your car under the carport and that is about how my rims stick outnow and if I measured right I have a 7 1/2 inch backspace, so I was thinking of going with a 295-40-17 just to be safe, what do you think.Sorry for all the questions but you have already done it so I guess you would be the best person to ask, thanks for all the replies so far.

Jazzer The Cat · 07-05-2008, 03:55 PM

To see exactly where back-space measuring is done, weneed to confirm we areconsistant with each other. If you have 7~1/2' back-space measured from the points in ***THIS*** link, than you should be VERY near rubbing as we speak. Double check your back-space and let me know. If you really are 7~1/2' back-space, you will most likely need spacers to go with a wider tire. To do so, you would need to replace your lug bolts with longer and stronger ones. I can give you the Moroso part # if necessary.

Keep in mind, you have 26mm to every 1'. So if you go from 275's ~ 295's, you will be approx. 3/4' wider tire. That will be about 3/8' wider on each side of wheel so you will have a little more bulge on sides.

Your welcome and happy to help. Let me know what your back-space measurement is based on the link in this post.

Jazzer

allnotch · 07-05-2008, 07:12 PM

Ya I went and measured and it is 7 1/2 backspace and about 1 1/2 to 2 inches from the shock and how your back wheel looks is how mine looks right now but it needs a little more tire! Do you think I can get a 295 on there without the spacer? My thinking is if I did the spacer and studs is that the wheel will stick out more than I would like because of the backspacing.

Jazzer The Cat · 07-05-2008, 09:04 PM

My wheel is 6~7/8' back-space EXACTLY. If you are 7~1/2', then your wheel is 5/8' farther toward inside of car. When your axle articulates heavily over an angle driveway or something (moving your tire upward and inward at the top inside edge).A 295~305' tire will almost certainly make contact with upper inside of back wall just above point at which shock enters trunk. This is not a huge deal as it should only hit when extreme angle and can be hammered in a little for clearance. My wheel is the same width as yours and has 1/2' spacers installed. Therefore, my wheel HAS to be farther out than yours so I cannot imagine you will not need spacers to avoid rubbing. If I am wrong, great!

, I certainly don't wish you to have rubbing issues, but hard to believe you will not.

I am 100% certain my axle is centered as well because I have PHB and centered it myself so it is even on both sides. You measured 1.5'~2' clearance between shock and tire, but did you measure with the axle at a severe angle, or articulated? This gap will lessen with wheel traveling way up into well. I had some rubbing prior to spacers and have 5/8' more room (due to wheel off-set) than you on the exact same car. One difference is I have PHB and torque arm with NO upper control arms, so articulation is a little different from yours. It is hard to describe difference, but I have additional clearance you do not have.

I would go ahead and run 295~305's, but plan on the possibility of running spacers. I installed new studs in an afternoon. I had to be VERY creative to install them and will be next to impossible to explain how I did it. I would recommend you take it to a shoppe to have it done.

I actually have my Summer set of wheels on the way and will be here next week [8D].I will be 10's up front running 295/30's and 11's out back running 315/30's. I will be installing Toyo R888's all around and looking forward to the twisties

. My SLA suspension up front allows the 10' wheel and could go to 10.5's and 315's if I really wanted to push it.

Jazzer