Dart & Valiant owners help w/ tire sizes

[chrisnben]

I'm needing to know if a 255 tire will fit in the stock 67-69 Valiant wheel opening without a leaf offset kit, or using SS springs, etc. I'm possibly game for a little lip trimming, but that's it.

What backspacing? From research, it's looking like 4.75 to 5.00" BS is right on a 8" rim

Or are we better off with a 7" rim? I'm trying to fit a 255 in there. :coffee2:

 

[pauly v.100]

255/40x18, 18x8.75 wheels, 6.25" backspace, +35 offset,`69 b-body rear end.
I used a ball peen hammer to create a little extra space on the inner fenders.
lowered, no spacers, no rubs

 

[69383valiant]

I have 15x7 cop wheels 4.25 backspace with 255-60-15's...Pictures are with stock original springs. They did rub in the top of the wheel well. Now have SS springs no rubbing at all...

 

[forced 340]

i have 255/60-15's on my 70 swinger with stock steel mopar wheels, redrilled small bolt 8.75 and drum brakes. i trimmed the lip a little and have no issues. the car sits low too. when i went disc brakes and bbp dr. diff axles, i had to trim the lip more because of the offset change in the axles and thickness of the rotor hat.

 

[MuuMuu101]

Chris, what rear end and brake package are you going to run? SSBC, IIRC for the brakes? My '68 Dart has 255/40/18's on the back. They rub on the outer trim a little because my rear end isn't centered due to factory tolerances. If I roll the fenders, it should be perfect, but I'm also going to be adding Dr Diff's leaf spring offset kit which should also gain me an extra 3/4". As for me, I used an A-body 8 3/4 with LBP axles, and Dr Diff's 11.75" disk brake kit. The wheels I used have an effective offset of +17mm and are 18 x 9's. Once you get the rear end in the car measure the distance from the face of your rotor to the inner trim of your fender and also to your leaf springs. Depending on your tire size, that will tell you what wheel you need to go with. I even made a cardboard cut-out wheel to reduce the chances of interference.

 

[chrisnben]

Chris, what rear end and brake package are you going to run? SSBC, IIRC for the brakes? My '68 Dart has 255/40/18's on the back. They rub on the outer trim a little because my rear end isn't centered due to factory tolerances. If I roll the fenders, it should be perfect, but I'm also going to be adding Dr Diff's leaf spring offset kit which should also gain me an extra 3/4". As for me, I used an A-body 8 3/4 with LBP axles, and Dr Diff's 11.75" disk brake kit. The wheels I used have an effective offset of +17mm and are 18 x 9's. Once you get the rear end in the car measure the distance from the face of your rotor to the inner trim of your fender and also to your leaf springs. Depending on your tire size, that will tell you what wheel you need to go with. I even made a cardboard cut-out wheel to reduce the chances of interference.

The A-body 8-3/4 is in the car. I'm looking at buying the FlexForm monoleafs too. I'll be using SSBC 10x1 discs (stole them from my other Mopar). GREAT idea of measuring from the rotor! Drop down with a straight-edge & measure in/out.

As I can tell, looks like a 8 x 17 rim & 255/50/17 tire will work. Guessing the wheel will need a 4.75 BS, both from other comments here, and my measurements with the stock steelie. Plus we'll have to use the offset spring kit.

Boy- I tell ya right now- the 255's won't last with this 500HP stroker going in! :burnout:

 

[Moparnutt340]

If you need more advice on specific model, you can also check out my new facebook group.
1967-76 Dart Swinger Scamp Valiant

 

[MuuMuu101]

The A-body 8-3/4 is in the car. I'm looking at buying the FlexForm monoleafs too. I'll be using SSBC 10x1 discs (stole them from my other Mopar). GREAT idea of measuring from the rotor! Drop down with a straight-edge & measure in/out.

As I can tell, looks like a 8 x 17 rim & 255/50/17 tire will work. Guessing the wheel will need a 4.75 BS, both from other comments here, and my measurements with the stock steelie. Plus we'll have to use the offset spring kit.

Boy- I tell ya right now- the 255's won't last with this 500HP stroker going in! :burnout:

Well, I have a 17 x 8" wheel with a 275/40/17 Nitto tire on it I used as a mock up and it is the same dimension as my 255/40/18 Michellin Super Sports on my 18 x 9" wheel. So with a 17 x 8" wheel, I'd imagine it would be able to suck in the sidewalls just enough to clear.

A 255/50/17 is an awfully tall tire. Are you going to go with that on all four corners? I'd imagine using a 255/45/17 should work. You'd probably have more tire options.

I'll be making 500+ hp with my stroker and I don't think my sticky 255's will last, especially in the autocross. That's why I'm installing the offset shackles so I can go to a 275/35/18 in the near future.