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Stock height 72 cutlass with sway bars, disk up front, drums rear.
Will 245/55R18's fit front and back? No rub, full turning ratio, no scrape etc...
If not, what are ALL 18" tires that will fit?
Thanks.
The internet shows those are 28.6" diameter and 9.6" wide, so they should fit on the rear with plenty of clearance assuming the correct wheel backspacing. I don't know about the front, though as those are fairly tall. I have 245-60-15s that are the same width and work on front without rubbing but they are 2" shorter than the tires you are looking at.
The internet shows those are 28.6" diameter and 9.6" wide, so they should fit on the rear with plenty of clearance assuming the correct wheel backspacing. I don't know about the front, though as those are fairly tall. I have 245-60-15s that are the same width and work on front without rubbing but they are 2" shorter than the tires you are looking at.
Ya I found the same info on the width, I just don't know how that height's gonna play out.
Hopefully some of the guys that run 18's will hop on with some experience running them.
Im running 245x45x18's on the front and 275x45x18's on the rears. They fit the arches well but I have discs alround, not sure if this makes a difference. The fronts rub on the inside when on full lock and I will be adding spacers just not got round to it, the rears can scrub on the arches when someones sat in the back, even my 12yr old can make this happen and I have Hotchkiss suspension fitted so its quite a firm ride.
Im running 245x45x18's on the front and 275x45x18's on the rears. They fit the arches well but I have discs alround, not sure if this makes a difference. The fronts rub on the inside when on full lock and I will be adding spacers just not got round to it, the rears can scrub on the arches when someones sat in the back, even my 12yr old can make this happen and I have Hotchkiss suspension fitted so its quite a firm ride.
Hmmm, so it sounds as if even the 45's are too tall huh?
That means the 50's are gonna be way too much.
If you had to do it over again would you go with the 45's or down to 40's?
Thanks.
Hmmm, so it sounds as if even the 45's are too tall huh?
That means the 50's are gonna be way too much.
If you had to do it over again would you go with the 45's or down to 40's?
Thanks.
I dont think going to 40's would make much difference to be honest, from memory its only around 10mm/13mm in height on the fronts and rears, doing it again I'd probably look at 17" rather 18". I am no expert mind but I do like the way they fill the arches
A 28.6" tall tire will likely be too tall for a Cutlass. The original tires were about 26.5" tall. I've run 255/60-15s, which are only slightly wider but over 1.5" smaller in diameter and they rub on a bump at full lock in the front. Obviously rim width and offset matter. My 255/60s were on factory SS II 15x7 wheels with zero offset.
These 22" were on this 64 Cutlass just a little rubbing.
But what was the tire OD and width? The smallest 22" tire you can get is 245/30-22, which is about an inch smaller in diameter than the 245/55-18s the OP is talking about.
My old wheels/tire combo was close to 29" rear and 27" front and that was close to the max diameter for a stock 70-72 before you will need serious mods. You may be able to go 27.1 or 27.2 in the front but then there just no more room for the tire to move in the wheel well without cutting/hammering.
I dont think going to 40's would make much difference to be honest, from memory its only around 10mm/13mm in height on the fronts and rears, doing it again I'd probably look at 17" rather 18". I am no expert mind but I do like the way they fill the arches
Lookin good! I just picked up these wheels today! Boss 338, they came on 235/40/18 fronts and 265/35/18 rear.
I think I'm gunna get your size tires for my 72. You're runnin 245/45/18 fronts and 275/45/18 rears correct?
My old wheels/tire combo was close to 29" rear and 27" front and that was close to the max diameter for a stock 70-72 before you will need serious mods. You may be able to go 27.1 or 27.2 in the front but then there just no more room for the tire to move in the wheel well without cutting/hammering.
Lookin real BEASTY! I like em! that's a good look!
I think I'm gunna get like you guys and go 45's. You have any rubbing issues?
Think I'm gunna do 245/45/18 front - 275-/45/18 rear.
Think I'm gunna do 245/45/18 front - 275-/45/18 rear.
I think that would be a good "safe" setup with no rubbing or issues (as long as you get the BS right!). You could do 18x8 and 18x9. Plus the height is good and will fill up the wheel wells nicely.
The 305s can be done but you need to do some minor mods (inner wheel well "massaging", roll outer lip, possibly relocate or mod tail pipes assuming they are 2.5" or 3") to make them fit and be 100% perfect on the backspace.
I think that would be a good "safe" setup with no rubbing or issues. You could do 18x8 and 18x9. Plus the height is good and will fill up the wheel wells nicely.
The 305s can be done but you need to do some minor mods (inner wheel well "massaging", roll outer lip, possibly relocate or mod tail pipes assuming they are 2.5" or 3") to make them fit and be 100% perfect on the backspace.
-Joe
That's what I got 18x8 & 18x9. Grabbin the tires today after work.
The only weird thing was the lug nut screws fit flush with the end of the stud. No length comes thru. I don't know if I should be concerned with this or nah?
My 4 way lug wrench couldn't even put on the rim because the rim holes are too small, I had to use a socket.
The stud pushes thru about a quarter inch past the lug nuts on my stocks.
I put an edit in my reply "as long as you get the BS right!" Even the smallest skinniest wheels and tires can be wrong with a bad BS. You need to make sure the wheel is properly centered for your car.
I put an edit in my reply "as long as you get the BS right!" Even the smallest skinniest wheels and tires can be wrong with a bad BS. You need to make sure the wheel is properly centered for your car.
I think the bs is 4 on both.
Is this acceptable for a 72?
It all depends on your setup. Better to mock everything up, measure and determine the perfect BS, then buy your rims. If everything is stock, I would guess a 4.5 on the 8s and I'm guessing around a 5ish on the 9s? If you are going to try to "make" the wrong BS wheel fit, you may need to go smaller on the tire or use spacers. The 245/275 combo is safe but if your BS is off too much it will definitely rub. Also if you make changes down the road to spindles or rotors or rearend etc your BS could end up needing to be changed.
-Joe
Correction - you won't be able to use spacers to make them fit if your BS is 4 for both. The tires will already stick out too far. I would confirm the BS first and do a test/mock up before you buy any tires! I don't think those wheels will work for you if they are really a BS of 4 for both unless you go with a REALLY skinny tire. About 1" skinnier rear and 1/2" skinnier front.
It all depends on your setup. Better to mock everything up, measure and determine the perfect BS, then buy your rims. If everything is stock, I would guess a 4.5 on the 8s and I'm guessing around a 5ish on the 9s? If you are going to try to "make" the wrong BS wheel fit, you may need to go smaller on the tire or use spacers. The 245/275 combo is safe but if your BS is off too much it will definitely rub. Also if you make changes down the road to spindles or rotors or rearend etc your BS could end up needing to be changed.
-Joe
Correction - you won't be able to use spacers to make them fit if your BS is 4 for both. The tires will already stick out too far. I would confirm the BS first and do a test/mock up before you buy any tires! I don't think those wheels will work for you if they are really a BS of 4 for both unless you go with a REALLY skinny tire. About 1" skinnier rear and 1/2" skinnier front.
Was just told rims are 4 (bs) front and 5x1/4 (bs) rear.
18x8 front with 18x9.5 rear.
Disc fronts, drums rear.
Recommendation?
I dont think going to 40's would make much difference to be honest, from memory its only around 10mm/13mm in height on the fronts and rears, doing it again I'd probably look at 17" rather 18". I am no expert mind but I do like the way they fill the arches
What's your front/rear backspace?
& did you go 18x8 front 18x9.5 rear?
You should try to limit total front tire height to between 26" - 27". If the car is lowered at all, or has older and sagging springs, I would stay between 26" and 26.5". You can easily run a 245 or 255 width in the front with no rubbing, but you need to have correct rim backspacing. The best way to maximize width is to get a used tire and use a wheel fit tool. To do this properly requires the removal of the front springs and fully articulating the front suspension while checking lock-to-lock clearances.
The tool is expensive, so if you don't have access to one, I would find out a specific rim with backspacing that others can confirm fit.
You should try to limit total front tire height to between 26" - 27". If the car is lowered at all, or has older and sagging springs, I would stay between 26" and 26.5". You can easily run a 245 or 255 width in the front with no rubbing, but you need to have correct rim backspacing. The best way to maximize width is to get a used tire and use a wheel fit tool. To do this properly requires the removal of the front springs and fully articulating the front suspension while checking lock-to-lock clearances.
The tool is expensive, so if you don't have access to one, I would find out a specific rim with backspacing that others can confirm fit.
Ok, so a front 245/45/18 being 26.7 tall is right in that range.
Seems like that's the route I'll be taking.
I totally agree with the suggestion to use a BS tool to check your setup. I'm guessing from the experiences on my cars but I think you are going to have issues/challenges with the 18x8 fronts and a 4" BS. To center a 245/45/18 tire on a 8" rim on a stock setup the BS should be around 4.5". The same tire on a rim with a 4" BS will leave a 1/2" of wasted space to the inside and push the tire to the outside 1/2" making it the same as if you were running a 275 tire to the outside. This means it will most likely hit/rub/need mods. You can try to drop down on the tire size to say a 235/45/18 which help for 2 reasons - first because the tire is .3" skinnier and second because it's .4" shorter. However these #s are then cut in half for how much they help you since it will only provide .15" more clearance to the inside and out and .2" more clearance with the shorter tire. So a 235 tire with a 4" BS on an 8" rim would make it about the same as a 265 tire to the outside so there could even still be rubbing or mods needed. The problem is with the BS that is too small. That's the killer because it pushes the tire out. The only option is to modify to gain clearance to the outside. If the 8" rims you had were too much BS like let's say a 5" BS = 1/2" too far to the inside, you can just use a spacer and your back to where you should be or maybe even just do a sway bar swap.
To be clear if you want to find a way to make these fit it can definitely be done but be prepared to possibly have to make mods to the fender and inner wheel well area if it hits. That just seems like a lot of work for a 245 tire when really you just need a properly BS'd rim and you're done. Coincidentally I'm in the process of trying to make a 305 tire fit on the front of my 442 for autocross and the mods are going to be many but that's to be expected. nTJEG56.jpg QoJT9Sm.jpg
I totally agree with the suggestion to use a BS tool to check your setup. I'm guessing from the experiences on my cars but I think you are going to have issues/challenges with the 18x8 fronts and a 4" BS. To center a 245/45/18 tire on a 8" rim on a stock setup the BS should be around 4.5". The same tire on a rim with a 4" BS will leave a 1/2" of wasted space to the inside and push the tire to the outside 1/2" making it the same as if you were running a 275 tire to the outside. This means it will most likely hit/rub/need mods. You can try to drop down on the tire size to say a 235/45/18 which help for 2 reasons - first because the tire is .3" skinnier and second because it's .4" shorter. However these #s are then cut in half for how much they help you since it will only provide .15" more clearance to the inside and out and .2" more clearance with the shorter tire. So a 235 tire with a 4" BS on an 8" rim would make it about the same as a 265 tire to the outside so there could even still be rubbing or mods needed. The problem is with the BS that is too small. That's the killer because it pushes the tire out. The only option is to modify to gain clearance to the outside. If the 8" rims you had were too much BS like let's say a 5" BS = 1/2" too far to the inside, you can just use a spacer and your back to where you should be or maybe even just do a sway bar swap.
To be clear if you want to find a way to make these fit it can definitely be done but be prepared to possibly have to make mods to the fender and inner wheel well area if it hits. That just seems like a lot of work for a 245 tire when really you just need a properly BS'd rim and you're done. Coincidentally I'm in the process of trying to make a 305 tire fit on the front of my 442 for autocross and the mods are going to be many but that's to be expected.
-Joe
Ok so I went with 245 45 18’s for the front and they seem to fit well. I haven’t driven the car yet but turned the wheel and it clears when turning all the way. I just don’t have a lot of stud length when applying the lugs. The stud fits flush with the End of the lugnut hole when screwed in but does not poke out if that makes sense.
Also I found the Factory stickers for the front wheels and found the offset to be 2mm on the 18x8’s.
