wheel fitment issue (suggestions needed)
Thread Starter
Racer
Joined: Nov 2010
Posts: 364
Likes: 0
From: Flower Mound TX
wheel fitment issue (suggestions needed)
I bought a set of tires and wheels for my 1972 vette.
the rears were riddler 18x9.5 with nitto 555 285x40zr18 which are about 27" tall
and they are just too tight in the wheel well since I did not have offset
trailing arms.
the fronts are 245x45zr17 so are about 25.6 tall.
I need a recommendation a new set of rear tires for that rim, that will bring the height
of the tire to about what the fronts are and for the side walls to not be so "bulgy". They rub the
inside of the tire badly plus I want also a similar sidewall look as the font.
I was thinking, 255x40ZR18. possibly 275/35 but unsure (due to side wall).
A side note, with the composite spring the rear end is just too tall,. I know I will need 10" bolts to bring it down, but I cant find them, and I don't think the spring would clear the tires or wheels.
So that is also part of my reasoning for shorter rear tire height.
Thanks. Maybe I should have done the offset arms a couple years ago lol.
the rears were riddler 18x9.5 with nitto 555 285x40zr18 which are about 27" tall
and they are just too tight in the wheel well since I did not have offset
trailing arms.
the fronts are 245x45zr17 so are about 25.6 tall.
I need a recommendation a new set of rear tires for that rim, that will bring the height
of the tire to about what the fronts are and for the side walls to not be so "bulgy". They rub the
inside of the tire badly plus I want also a similar sidewall look as the font.
I was thinking, 255x40ZR18. possibly 275/35 but unsure (due to side wall).
A side note, with the composite spring the rear end is just too tall,. I know I will need 10" bolts to bring it down, but I cant find them, and I don't think the spring would clear the tires or wheels.
So that is also part of my reasoning for shorter rear tire height.
Thanks. Maybe I should have done the offset arms a couple years ago lol.
Melting Slicks
Joined: Apr 2002
Posts: 2,337
Likes: 14
From: Norfolk VA
I bought a set of tires and wheels for my 1972 vette.
the rears were riddler 18x9.5 with nitto 555 285x40zr18 which are about 27" tall
and they are just too tight in the wheel well since I did not have offset
trailing arms.
the fronts are 245x45zr17 so are about 25.6 tall.
I need a recommendation a new set of rear tires for that rim, that will bring the height
of the tire to about what the fronts are and for the side walls to not be so "bulgy". They rub the
inside of the tire badly plus I want also a similar sidewall look as the font.
I was thinking, 255x40ZR18. possibly 275/35 but unsure (due to side wall).
A side note, with the composite spring the rear end is just too tall,. I know I will need 10" bolts to bring it down, but I cant find them, and I don't think the spring would clear the tires or wheels.
So that is also part of my reasoning for shorter rear tire height.
Thanks. Maybe I should have done the offset arms a couple years ago lol.
the rears were riddler 18x9.5 with nitto 555 285x40zr18 which are about 27" tall
and they are just too tight in the wheel well since I did not have offset
trailing arms.
the fronts are 245x45zr17 so are about 25.6 tall.
I need a recommendation a new set of rear tires for that rim, that will bring the height
of the tire to about what the fronts are and for the side walls to not be so "bulgy". They rub the
inside of the tire badly plus I want also a similar sidewall look as the font.
I was thinking, 255x40ZR18. possibly 275/35 but unsure (due to side wall).
A side note, with the composite spring the rear end is just too tall,. I know I will need 10" bolts to bring it down, but I cant find them, and I don't think the spring would clear the tires or wheels.
So that is also part of my reasoning for shorter rear tire height.
Thanks. Maybe I should have done the offset arms a couple years ago lol.
Thread Starter
Racer
Joined: Nov 2010
Posts: 364
Likes: 0
From: Flower Mound TX
I don't have pics of it and not sure how pics would help on a suggestion for tire widths. I have looked around and have seen post where people went 255 and 275. I am trying to see if one is better than the other. Just want the inside wall to be further away from the TA
Thread Starter
Racer
Joined: Nov 2010
Posts: 364
Likes: 0
From: Flower Mound TX
well after thinking about things like the wheel rubbing, the spring being awful close etc, I realized the issue is (in part) is the 1/2" backspace difference.
that 1/2 inch pulled my wheel too far into the wheel well. The 285 may be par of the issue also.
I will have to do something to move the wheel out form the hub some. I don't like the idea of the 1/2 spaces that fit over the existing posts. I am thinking of maybe the bolt on spaces to move them out some, but the smallest is 1" so that would then push the wheel out 1/2" further than factory.
I want the car to be safe for my wife since she will be driving mainly.
that 1/2 inch pulled my wheel too far into the wheel well. The 285 may be par of the issue also.
I will have to do something to move the wheel out form the hub some. I don't like the idea of the 1/2 spaces that fit over the existing posts. I am thinking of maybe the bolt on spaces to move them out some, but the smallest is 1" so that would then push the wheel out 1/2" further than factory.
I want the car to be safe for my wife since she will be driving mainly.
Burning Brakes
Joined: Jan 2006
Posts: 1,088
Likes: 181
From: NC
2022 C2 of the Year Finalist - Modified
Is the rear tire rubbing on the trailing arm or on the chassis? Usually with 18 inch wheel/tire the tire will rub the chassis first
If its rubbing on the chassis, just get a 1/8"-1/4" spacer and move the wheel/tire out some.
BILL
If its rubbing on the chassis, just get a 1/8"-1/4" spacer and move the wheel/tire out some.
BILL
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
I have 1/4" spacers on my Cragars to clear the calipers. No problem and I am over 500 HP.
Pro
Joined: Dec 2006
Posts: 695
Likes: 5
From: tx
I'd suggest getting the backspace number you need/want before doing anything else. The issue is predominately the wheel backspace not the tire. The factory wheel backspace is 4". What is the backspace of the wheel you bought? I run a 18*9.5 in the rear with a 5" backspace with virtually no issues. Can you exchange the wheels for a pair with a different backspace? This is why you measure, measure again and measure again.
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
Here's a chart I made that is handy when deciding on tires.
Here's a good source for spacers.
Motorsport Tech
Here's a good source for spacers.
Motorsport Tech
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Race Director
Joined: Jan 2007
Posts: 14,959
Likes: 3,354
From: NYC NY
I'd suggest getting the backspace number you need/want before doing anything else. The issue is predominately the wheel backspace not the tire. The factory wheel backspace is 4". What is the backspace of the wheel you bought? I run a 18*9.5 in the rear with a 5" backspace with virtually no issues. Can you exchange the wheels for a pair with a different backspace? This is why you measure, measure again and measure again.
That wheel width and size tire should work with a 5" backspace.
Racer
Joined: Jan 2005
Posts: 370
Likes: 77
From: Perth Western Australia
I'm using 275/40R18 rear tire with a 5.25" back space with no rubbing, however I'm using a shortened spring.
As for the 10" bolts there C4 bolts from VB&P.
Standard trailing arms will work with 18" rims but you may have to relocate the e bracket to the top of the arm.
Thread Starter
Racer
Joined: Nov 2010
Posts: 364
Likes: 0
From: Flower Mound TX
I am going to go with a spacer 1st. I am trying to decide on a spacer spacer or an adapter that will move it out a little more. The main reason I am thinking of the adapter is because it will mount on the existing lug posts, and the wheels connect to the posts on the adapter.
I am going to take some measurements 1st. the adapters are 1" which would move it 1/2" further out than factory, so it wold be like a 4.5 BS. I get the feeling that it may be a little too much toward the outside.
But I do agree get the back space done 1st, then make other decisions.
And yes, I did already relocate the ebrake cable. I actually think it looks better than way than having it on the side.
I am going to take some measurements 1st. the adapters are 1" which would move it 1/2" further out than factory, so it wold be like a 4.5 BS. I get the feeling that it may be a little too much toward the outside.
But I do agree get the back space done 1st, then make other decisions.
And yes, I did already relocate the ebrake cable. I actually think it looks better than way than having it on the side.