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Selecting Rims to Fit VH Wagon

RoChester

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I have a VH Wagon and am in the process of getting a VL diff built to suit.
There's currently 17 x 8 with 225's, can just fit my hand up between the wheel and the guard so not a lot left over but a good fit, don't think with current setup would go any bigger though.
Now, as a bit of a newbie to doing a rebuild this ones got me confused. I'm putting a 355 in with about 450 so need some decent tread on the rear, how do I go about picking the right wheels and offset with a new diff being built at the same time ?
The diff is going to be shortened, evidently can only shorten the wagon diff about 25mm says the diff builder.
Another company is building billet axels to suit and told me to just go buy the wheels I want and they'll do the rest and make it fit.
There's seems to be plenty of room on the inside of the rim to go bigger, hopefully a 245 but surely I need to work out an offset and the rest gets built to fit that ?
Should I try and work out the offset of the current old rims and go from there ?

Confused as F.
 

vc commodore

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I have a set of 16X8's with 225's on my VC, with just over a fingers gap between the tyre and the inner guard, which isn't rolled...Unsure of backspace, but from the back of the bolt up face to the rim edge is 190MM give or take 5 MM.

I also have a set of 16X7 factory VT or VX rims (can't remember the model they're from)....48P is the back space, fitted with 225's fitted to them...Without bolting them on the car, I reckon I have 2 to 3 finger space between the tyre and guard with them....I've just decided to stick with my 16X8's for guard fill

So with a 48 P wheel, 235's will be ample clearance.....
 

Sandman

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Willtheyfit.com

Use this site and plug in your specs. add or subtract the amount of diff shortening from the offset to see how they fit. I run a 245/60/15 on a 15x7" +43 steel wheel with a standard length 8 bolt salisbury. Use those specs as a 'before' and work out what suits with your length diff and what offsets are available from wheel manufacturers for whats available.
 

RoChester

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Willtheyfit.com

Use this site and plug in your specs. add or subtract the amount of diff shortening from the offset to see how they fit. I run a 245/60/15 on a 15x7" +43 steel wheel with a standard length 8 bolt salisbury. Use those specs as a 'before' and work out what suits with your length diff and what offsets are available from wheel manufacturers for whats available.
That's a pretty handy site, I think what I need to do to get it working is find out exactly the width the diff is going to be, the wagon 8" diff is wider than the sedan, shouldn't be hard to find out how much, the new diff is going to be about 12 mm shorter on each side, however is a VL wagon and VH wagon the same size, but thats what the diff builder said, 25mm shorter. Got me confused when the bloke doing the axels said just buy the wheels you want and we'll make the diff to suit. builder saying can only shorten by 25mm, axel builder saying buy wheels we'll make it fit. anyway got some googling to do.
 

RoChester

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That's a pretty handy site, I think what I need to do to get it working is find out exactly the width the diff is going to be, the wagon 8" diff is wider than the sedan, shouldn't be hard to find out how much, the new diff is going to be about 12 mm shorter on each side, however is a VL wagon and VH wagon the same size, but thats what the diff builder said, 25mm shorter. Got me confused when the bloke doing the axels said just buy the wheels you want and we'll make the diff to suit. builder saying can only shorten by 25mm, axel builder saying buy wheels we'll make it fit. anyway got some googling to do.
It's actually a Salisbury 10 bolt, getting myself confused about what I've even got now....
 

gtrboyy

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Wagons supposedly same from vb to vl from back half of car other than diff & wheels.

vl b/w is wider than salisbury...don't know if wagon diffs versus sedans are actually wider or just confusion over disc vs drum widths that do change track a little due to brakes & axle seal differences.

If they're doing custom diff starting with cheaper vn-vs ute/wagon diff may as well get wheels you want that fit & get diff made to suit.

It may handle better with 17x8 rims & 225 low profile tyre but it won't hook up any better going 245 tyre as won't really be much difference in sidewall or circumference tbh.

A lot of variables & use of car come into play determines how to go about the build especially if choosing traction over handling which usually means jamming tallest tyre & width with suitable suspension that match driveline....can make a car be cool cruiser that can rip at drag strip or something that likes to swap ends & feels slow when you get used to 450hp engine.
 

RoChester

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Wagons supposedly same from vb to vl from back half of car other than diff & wheels.

vl b/w is wider than salisbury...don't know if wagon diffs versus sedans are actually wider or just confusion over disc vs drum widths that do change track a little due to brakes & axle seal differences.

If they're doing custom diff starting with cheaper vn-vs ute/wagon diff may as well get wheels you want that fit & get diff made to suit.

It may handle better with 17x8 rims & 225 low profile tyre but it won't hook up any better going 245 tyre as won't really be much difference in sidewall or circumference tbh.

A lot of variables & use of car come into play determines how to go about the build especially if choosing traction over handling which usually means jamming tallest tyre & width with suitable suspension that match driveline....can make a car be cool cruiser that can rip at drag strip or something that likes to swap ends & feels slow when you get used to 450hp engine.
Thanks mate, some good info in there again.

My comment on the diff being wider was in regards to the wagon being wider than the sedan, you may be right with the drum and disc bit.

I'm just repeating what diff builder said, in turn making wheel selection more limiting. I'm having a VL wagon diff rebuilt and then shortened, this might bring it back to more like the sedan width, the builder says can only shorten VL diff up to 25mm, don't know why that is, when axel builder says buy wheels and we'll build to suit, there's obviously only a certain max width that will fit on the back and that has to be only with a certain offset rim, this is where I get confused.

I just don't want to go and spend a small fortune on wheels because they're the ones I want, then find I can't fit em in.

Your right there isn't much difference between a 225 and a 245 but I think I'll need as big as I can get in there.
 

_R_J_K_

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48P is the back space
Offset and backspace aren't the same, backspace is mounting face to the back of the wheel (measured in inches) and offset is mounting face to the centreline of the wheel.
the builder says can only shorten VL diff up to 25mm, don't know why that is, when axel builder says buy wheels and we'll build to suit, there's obviously only a certain max width that will fit on the back and that has to be only with a certain offset rim, this is where I get confused.
Probably that the axles can be made to fit a completely custom diff housing for a tubbed or tube frame rear which can be extremely short and have the mounts placed at any point, but since you're using a stock diff there's only so far inward that the diff can be shortened. You need to find find out how much is being shorted per side and total width just to make sure. For your existing wheels they might have the offset and width stamped or cast into the back of the wheel.

The offset will also come down to how aggressive you want the fitment to be and how wide you want to go. There are a few threads on Calais Turbo that say they can get 10" wide wheels under VLs before having to go to tubs with carefully picked offsets - and you can do that without shortening the diff by factoring in offset (although depending on wheel design they can have more dish with a more negative offset). That would be really pushing the limit and you would probably need to pull every clearance trick out of the book to do it, but it's doable. Have pulled off a 10.5" wide 18" wheel on a VS Grange before to give you some idea, totally unmodified save for some lip rolling and inner guard massaging. A good starting point is to find some builds that have the kinds of wheel specs you're looking for (or close to it) and work from there.

It will also depend on the kind of wheels you're looking at and how customizable they are, as you'd probably need a fairly high positive offset for some of this which could be limited by how the wheel is manufactured or the brand's sizing steps. Got any in mind?
 
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RoChester

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Offset and backspace aren't the same, backspace is mounting face to the back of the wheel (measured in inches) and offset is mounting face to the centreline of the wheel.

Probably that the axles can be made to fit a completely custom diff housing for a tubbed or tube frame rear which can be extremely short and have the mounts placed at any point, but since you're using a stock diff there's only so far inward that the diff can be shortened. You need to find find out how much is being shorted per side and total width just to make sure. For your existing wheels they might have the offset and width stamped or cast into the back of the wheel.

The offset will also come down to how aggressive you want the fitment to be and how wide you want to go. There are a few threads on Calais Turbo that say they can get 10" wide wheels under VLs before having to go to tubs with carefully picked offsets - and you can do that without shortening the diff by factoring in offset (although depending on wheel design they can have more dish with a more negative offset). That would be really pushing the limit and you would probably need to pull every clearance trick out of the book to do it, but it's doable. Have pulled off a 10.5" wide 18" wheel on a VS Grange before to give you some idea, totally unmodified save for some lip rolling and inner guard massaging. A good starting point is to find some builds that have the kinds of wheel specs you're looking for (or close to it) and work from there.

It will also depend on the kind of wheels you're looking at and how customizable they are, as you'd probably need a fairly high positive offset for some of this which could be limited by how the wheel is manufactured or the brand's sizing steps. Got any in mind?
Yeah I am leaning toward Simmons V5s.
It has 17's with a 50 profile on now and they fill out the guard nicely height wise, but I've been told I'm better off going for a 16" or even 15" with a bigger profile to get some traction.
Ok, thats interesting, 10" wide with the right offset, so sticking to 8" I should get a 245 in there no probs then.
Just found out VN axels will go into a VL diff just have to get changed from 32 spline to 28 spline, that could save me a shitload on getting billet ones made up.
Helps talking to the right people...
 

vc commodore

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Offset and backspace aren't the same, backspace is mounting face to the back of the wheel (measured in inches) and offset is mounting face to the centreline of the wheel.

My 16X8's I can't find the offset, where the 16X7 factory wheels I can....This is why I posted up the measurement from the mount up face to the rear lip of my 16X8's as a reference
 
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