How to measure for new backspace? (17" Billet Magnums)

[Pakrat 1,043]

OK, I've read tons of articles on how to measure backspace but they all show the same obvious way to measure your existing backspace on your existing rims which reflects your existing setup. So I assume that for example since my rears are probably staying drums for now I can simply lay a straight board across the back of my old 14X7” rims, then measure down to my base and get the current back space. Now when I go to my new 17” rims I would keep it the same for if I kept it 8” also, but if I want to go meatier in the back do I split the difference? So say if I want 8” then do I add a ½ inch to my backspace and for 9” add a full inch to it?

Also, what about when I do the disc conversion to the front, the old 14’s won’t even fit for a reference so how the heck do9 I figure it out? If I was just messing with spacers I could do trial and error, but since the billet Magnums have to be ordered with custom backspacing I have one shot to get it right. They are too pricey to make a mistake on.

[69boss429 106]

OK, I've read tons of articles on how to measure backspace but they all show the same obvious way to measure your existing backspace on your existing rims which reflects your existing setup. So I assume that for example since my rears are probably staying drums for now I can simply lay a straight board across the back of my old 14X7†rims, then measure down to my base and get the current back space. Now when I go to my new 17†rims I would keep it the same for if I kept it 8†also, but if I want to go meatier in the back do I split the difference? So say if I want 8†then do I add a ½ inch to my backspace and for 9†add a full inch to it?

 

Also, what about when I do the disc conversion to the front, the old 14’s won’t even fit for a reference so how the heck do9 I figure it out? If I was just messing with spacers I could do trial and error, but since the billet Magnums have to be ordered with custom backspacing I have one shot to get it right. They are too pricey to make a mistake on.

With your stock wheels and tires in place on the rear,measure how much clearance you have to the spring or any component that protrudes outboard.Allowing for 1 inch away from any of these items should let you increase the backspace accordingly.i.e. 2inches away add 1 inch to backspace and increasing rim 1inch.Fronts,you have to watch for clearance to the spindle as well as everything else.

[Pakrat 1,043]

So basically there is no simple rule of thumb or easy formula to apply? I just have to double, triple, quadruple check the front from every and all aspects and then cross my fingers and hope for the best?

 

Since you have the exact rim I'm getting, may I ask what is your particular set up?

 

Rear Brakes?

Rim size?

Backspace?

 

Front brakes?

Rim Size?

Back Space?

 

Also, did you go with wheel vintiques, Newstalgia or a another vendor I have yet to stumple on?

[69boss429 106]

So basically there is no simple rule of thumb or easy formula to apply? I just have to double, triple, quadruple check the front from every and all aspects and then cross my fingers and hope for the best?

 

Since you have the exact rim I'm getting, may I ask what is your particular set up?

 

Rear Brakes?

Rim size?

Backspace?

 

Front brakes?

Rim Size?

Back Space?

 

Also, did you go with wheel vintiques, Newstalgia or a another vendor I have yet to stumple on?

I purchased the Wheel Vintiques from Newstalgia Wheels. 17x8 front 4.5,17x9.5 rear 5.5.Went with 17's to clear Baer rotors.But remember,Boss 429 fenders were rolled from the factory.Measure as stated previously before ordering.

[Pakrat 1,043]

I purchased the Wheel Vintiques from Newstalgia Wheels. 17x8 front 4.5,17x9.5 rear 5.5.Went with 17's to clear Baer rotors.But remember,Boss 429 fenders were rolled from the factory.Measure as stated previously before ordering.

 

Oh that's weird, I thought Wheel Vintiques and Newstalgia were competitors, hunh. Anyway, yeah same here, I'm going with them to clear my 13" Cobra Discs up front, I'm leaving the drums out back for now though. I will definitely measure first though, i just wanted some kind of reference point and now I have it, thanks!!!

 

So one last question, what did you end up stuffing under there tire wise? Like a 255/40 and a 275/40?