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17's/18's Help please

Ok I am planning to run mustang gt 13.2 front disc brakes in the front with Mustang steve's kit and the 2005 and up mustang rear brakes using mustang steve's kit. I am trying to plan this all out. So now I am working on wheels and tires since I can't use the stock wheels with these kind of brakes.

I am looking at 17's or 18's. I was told that 18's might be the way to go to clear something in the ear suspension area? Anyone know what that is? I have been looking at 17x8-9.5's or 18x8-9.5s, What are the guidelines I need to keep in mind in order to get a great look and good performance? what is the largest I should go front and rear? I am thinking going the same size all the way around will help save tires by being about to rotate etc. I am going to be using the car to drive around to the beach etc, hit the strip, possible trips to vegas, auto cross, maybe some road racing at willow springs etc.

Is it safe to say that I want to stick with a 4-5inch back spacing or around a 0mm offset? Let me know your thoughts and advice.

Thank you,
 
The year car you have along with what modifications is a pretty critical piece of information...
 
1968 mustang coupe. 351 Cleveland. Still working out suspension. Motor will have header back exhaust upgrades, intake, card, and slowly get up in hp/tq.
 
I have a 67 which is very close to the 68 but it's modified. If you are going to drop a lot of cash on wheels, it's best to measure, measure, measure. I know the cars should all be the same but they are not. Rear is a lot more forgiving since the tires do not have to steer. Changing brakes and different brake kits can effect how much the wheel moves in or out from an original set-up depending on thickness of the rotor(s). It's usually it's not much but if your considering 9.5" wide rims you don't have a lot of play room.
I am running a Lincoln Versailles 9" rear which is narrower than stock. I have 17x9.5" with 5.5" BS. I had to special order them. I had 17x8" with 4.75" BS with 1" spacers before that.
On the front I have 16x7" with 4" BS. I think I should have a little more BS so I can lower the front end with-out rubbing. I had the car sitting lower but the tires rubbed when turning and hitting bumps. I run the Granada spindles so I don't know how much that effected the "track" width but I suspect it's a slight bit wider.
Tread width is a factor too. Each tire will will have a slightly different cross sectional width. You need to look at the tire specs when measuring and sizing it all up.
 
18s do not look good on these cars, IMHO. They also leave no room for a decent tire for purposes of drag racing. You are trying to make a "do all" car to the last degree so you need to walk the center line in most areas. What serves one purpose many times hurts another. A big wheel with a very low-profile tire is not going to help you one bit at launch. The larger rotational mass isn't going to do you any favors either.

Your car will weigh considerably less than a modern Stang. Do you really think you need to run huge brakes? The move to a disc set-up in front alone will make a HUGE difference. Unless you are planning on really doing some serious road course type racing you can probably back off some on your brake plans.
 
Are you saying to install the brakes first and then try and measure out the room I have first? If I go that route, without a tire/wheel under their, what are the measurements I should take? from the rotor to the frame rail in the rear and from the rotor to the fender lip? Never measured in the wheel well's for tires. I have just been guessing based off of what others have said they are using.

When they say 0mm offset etc, how do you measure or what do you measure for that? I get back spacing is the from the rotor mounting pad inward.
 
Talk to Nick (Dodgestang). He is the know-it-all on wheel fitment and he has a 68, too. Craig has a good point about differences between cars so be aware. The simplest thing to do is mount up a wheel and see what clearances you have and then use that as a baseline for where other wheels will line up. Most brake kit suppliers can tell you what if any affect their kit will have on change to wheel position.

Here's a link to his fitment chart

http://www.dodgestang.com/emAlbum/album ... 2067-8.pdf
 
what he said...

"68angrypony" said:
Are you saying to install the brakes first and then try and measure out the room I have first? If I go that route, without a tire/wheel under their, what are the measurements I should take? from the rotor to the frame rail in the rear and from the rotor to the fender lip? Never measured in the wheel well's for tires. I have just been guessing based off of what others have said they are using.

When they say 0mm offset etc, how do you measure or what do you measure for that? I get back spacing is the from the rotor mounting pad inward.
If you don't have access to a lot of fancy tools or want to fab up some, the simple way is as Terry says. Take your stock wheel and go from there. A simple straight edge across the back of the rim with a tape measure to the mounting point (where the studs go thru the holes). That will give you back space (BS). Lay your tire on a flat surface with a straight edge across the sidewall (yard stick) and take your tape meaasure from that to the ground. That is your tire cross section. Now turn your wheels as far as you can either way and measure how close the tire comes to the frame or other points. Remember diameter will factor in as well. Over all tire height may be the same on a 14" 195 70 as a 17" 275 45 but where the wide part is will obviously be further away from center on the 17" wheel. Once you have a feel for fender and frame clearance you can start looking at available wheels and tire combos. This will give you an idea how far you can go. The link provide is great be consider some cars are not exact. In fact I found I have about an 1/8" more clearance on my passenger side rear wheel well than the drivers side.

I went wider a few years ago on the rear, here is an example of the tire difference
REAR TIRE SIZE SECTION DIA TREAD WIDTH
FIREHAWK 245/45 ZR 17 9.6 25.7 8.6
Maxxis 275/40/VR17 10.9 25.6
 
"Horseplay" said:
18s do not look good on these cars, IMHO. They also leave no room for a decent tire for purposes of drag racing. You are trying to make a "do all" car to the last degree so you need to walk the center line in most areas. What serves one purpose many times hurts another. A big wheel with a very low-profile tire is not going to help you one bit at launch. The larger rotational mass isn't going to do you any favors either.

Your car will weigh considerably less than a modern Stang. Do you really think you need to run huge brakes? The move to a disc set-up in front alone will make a HUGE difference. Unless you are planning on really doing some serious road course type racing you can probably back off some on your brake plans.

That makes great sense. It just seems that it would give me great braking and be more cost effective than using the original brakes as the k/h's seem over 500 just for the front. later model would require changing the front spindle and looks to cost a lot more as well. With the way people drive around where I live I also figured having a car that stopped as well as a new car would be a great safety feature so I can prevent any situations where my car doesn't brake in time. K/h calipers alone are pretty pricey and so if something happened to one would be a pretty penny to replace where newer car parts are going to be easier to come by and abundant in the next several years. Not sure what the car will end up doing. But if I could get into racing at some form That would be a fun thing to do with a weekend car. That being said, most newer cars seem to be running a 17 inch or larger wheel so I can't imagine that 17/18's would be that bad in areas of performance. For drag racing I know I could also get just a cheap set of 17's or smaller for the rear since the rear brakes are 11.85's I think with race tires and just swap them at the track. So I am of the impression that its possible to get the car where it can be used for a few different things. A vette, newer mustangs, etc., can go to the track and run 13's or below, be able to run auto cross, and head up to do road course racing at willow springs. I am not looking to be a pro racer or to have the fast car at the track. Just a fun car that is faster then the group of buddies I do go and race with. They all have daily driver cars that are newer such as new taurus eco boost, super charged 02 vette, grand prix gtp, mustangs, etc. I don't have a truck or a trailer right now so its not going to be a tow queen. Its just meant to be a great all around car IF possible. I could run low to mid 12's at the track and still auto cross, road course race etc
 
keep in mind that big brakes can stop the tire from spinning but that doesn't necessarily mean the car will stop moving. New cars have ABS and traction control and other computer aids to help braking efficiency. I can lock up all four wheels on my 67 in a panic stop with Granada disc's in front and Versailles in the rear and that's without a power booster. (Heavy Foot needed).
Getting a 68 Mustang to be competitive with an 02 Vette or new SHO is not going to be easy or cheap, but you can have the best looking Hot Rod of the bunch!
 
So in essence the big brake kits are useless? Is that pretty much everyone's thoughts is that you should do a granada/kh/ 68 and up disc brake set up? obviously I don't want to wast e money or to deal with problems. I just want to build a car that is as good as I can make it. Obviously 15 inch wheels and tires even 16's would be a lot cheaper I'm guessing. Hard to make choices as a rookie not knowing what to use to get what I want from this car :roul
 
"68angrypony" said:
So in essence the big brake kits are useless?
NO NO NO, I just mean there is more to consider than simply how big the rotors are. Obviously bigger brakes grip better but mostly they dissipate heat or don't get as hot under repeated use. If your building a mild street car, you don't need the biggest brakes you can buy. It's just a matter of purpose vs budget
 
My car is a "driver" it's not really great at anything but is a good balance. I used the Granada/Versailles stuff before there were a lot of after market stuff out there. I don't race it but I can push it hard on occasion. I don't have a ton of money into it and I can drive it anywhere. If money was no object I'd go big brakes on mine but I'm not rich! It sounds like you might be trying to build the same type of car. One you can have fun with, push harder than a stock one and still eat out once in a while...
 
For the price I don't think I could do it cheaper. The 13.2's come with a dual piston aluminum calipers and you can get both front calipers, pads, and rotors with less than 2 miles on them for 150 shipped off ebay from roush. They take them off to put their stuff on. At that price plus the bracket costs, I didn't really think I could go wrong as I would be getting superior braking for around 325 plus the little items to make it work on the car. Say 400 bucks and I have a 2012 set up. Looking at K/h calipers are over 100 a piece plus brackets are 50 a piece etc. It seemed for less money I would be able to get a superior brake set up that would be easier to get parts for as they are going to be in abundance. The newer rears are about the same price. So I don't fab, if I were to have someone make me brackets that would cost, so for bolt on you are always paying to get brackets which seem to be the most expensive part. I just believe that if you can do it right the first time then why not. If i do 13.2's in the front with dual piston calipers and newer brakes on the rear, no matter how I build the car, I don't think I will ever need "more" brake power. Its like a brembo, wilwood, other kit etc. Maybe even one day I could figure out how to add some abs if that's possible and have an amazing set up. That's my thinking. Am I completely off my rocks with my train of thought? I never see older cars at the junk yards around here, went to 5 over the last few weeks, and if their is something older it gets stripped. So at that rate its buying online and for 325 for some crazy brakes, I don't see to many downsides except having to use bigger wheels. Am I missing anything in my thought process? :char
 
As long as you stock track width a 17x8 with 4.75 backspacing a 235 45 17 tire will easily fit all way around. Similarly an 18x8 with 4.75 backspacing fits.
 
"tarafied1" said:
My car is a "driver" it's not really great at anything but is a good balance. I used the Granada/Versailles stuff before there were a lot of after market stuff out there. I don't race it but I can push it hard on occasion. I don't have a ton of money into it and I can drive it anywhere. If money was no object I'd go big brakes on mine but I'm not rich! It sounds like you might be trying to build the same type of car. One you can have fun with, push harder than a stock one and still eat out once in a while...

This is true. Would like to be able to go racing with friends and knock most of them out if I can. But looking at brakes, even if I find something cheaper, most of the time you want to get new calipers and their is always a core charge and I have no cores. Since I can't fab and I am a rookie, I know I will have to pay a few bucks more to do things like this as I am at the mercy of others kits etc. I'm trying my best to say up and only spend what is needed to get the car going. But some things like brakes, just seems worth it to do it right the first time. Dumping money into getting the drum brakes working seems like a waste as its 100-200 that would go towards the better brakes and I know for sure I want disc brakes. My mechanic buddy told me to not drive the car until I put at least fronts on and if he is telling me that then I head the advice, He didn't say big brakes, that was my own thoughts lol. Having a manual transmission will help as I can down ship along with the big brakes so I know the car would have pretty amazing stopping ability with good times/wheels/brakes (suspension too) and being able to down shift. right? lol
 
"dodgestang" said:
As long as you stock track width a 17x8 with 4.75 backspacing a 235 45 17 tire will easily fit all way around. Similarly an 18x8 with 4.75 backspacing fits.

What would that look like in terms of offset? seems a lot of wheels are using offset instead of back spacing. Will offset tell me anything or do I have to know the back spacing. For example, if I used an 18x8 set up with 0mm offset would that tell me anything for fitment?
 
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