I suck at wheels. Need help with offset and fitament.

[Topher]

Yes. And Yes.

 

 

Assuming your questions are:

 

1. Are you new?

2. Did you search?

 

 

Long story of the car and pictures: http://forums.hybridz.org/showthread.php?t=127874

 

 

Looking to pick up some wheels. Still a bit confused. As it stands I am on Eibach and Tokico springs/struts. I will eventually move to the AZC coilover setup.

 

I have found two sets of wheels I am interested in:

 

Wantabe RS8

 

 

Specs are: 16x7+38 114.3 4h 16x8+38 114.3 5h

 

 

 

Volk GTU

 

 

Specs are: 16x7+35 16x8+35

 

 

Simple question: Will these work?

 

 

Loaded question: Will these work? (i.e. what do I need? Spacers and rolling fenders don't scare me; assuming it isn't drastic, i.e. huge spacers or involve over fenders, etc.)

 

Thoughts?

 

Thanks!

[(goldfish)]

Quickly looking, I say the wat's will, the volk's will need spacers.

 

oops, I think I looked to quick, are both 38 offset? Then they both need spacers. But I'm not to sure on the exacts.

[veritech-z]

You need a spacer for both of those offsets. 1.5" will do. The volks actually have 3mm less offset than the Wats, but a 1.5" spacer would accomodate either wheel. Lowering a lot may require fender rolling, but up to an inch lower I can vouch does not need rolling. I personally like the volks better.

 

Here's how a 17X7/17X8 +38 offset wheel fits with a 1.5" spacer and a 1" drop if it helps you any.

[Topher]

Quickly looking, I say the wat's will, the volk's will need spacers.

 

oops, I think I looked to quick, are both 38 offset? Then they both need spacers. But I'm not to sure on the exacts.

 

 

I ninja edited my post.

 

There are actually two sets of wheels for the Watanabe

 

Specs wheel set 1 ($600): 16x7+38 114.3 4h 16x8+38 114.3 5h

 

For the other set of identical looking Watanabe (but $800): 16x7+13 114.3 4h 16x8+14 114.3 4h (I am assuming the offset is the 13/14?, just seemed odd)

 

 

Again, these are BOTH specs for the Watanabe RS8 just apparently different offset.

[Topher]

Oh and Goldfish, where are you at in Minneapolis?

 

I live in NE, Mpls. In the Audobon area.

[Topher]

To further compound it...

 

 

Any suggestions on tire size?

 

225/50 front?

255/50 rear?

 

Man I suck.

 

It's easy to buy wheels for my Saab.

 

 

Edit: wow, there isn't much of a tire selection for that rear sizing...

[veritech-z]

A 7" wide wheel with a +13 (roughly .5") offset should fit the S30 with no spacer, but you may need a spacer for the 8". Unless you do the adjustable coilovers at the same time, those add some clearance for more backspace.

[buZy]

Great to see another twin cites member!

[Topher]

Great to see another twin cites member!

 

Yeah, that's pretty sweet. There are a lot of local guys on the Saab and Subaru board and we get together a lot to go run sanctioned events (autox, track days, rallyx, hill climbs, etc).

 

Someone shoot me a pm next time you guys meet up.

 

 

So back to the wheels!

 

What do you guys think, Volks or the Wats?

[johnc]

Offest is only useful in calculation backspace. For a 240Z running stock diameter springs you can run a wheel with 3.5" to 3.75" of backspace - assuming your tire sidewall is vertical and not bowed out (tread width wider then rim width). At 4" there's a good change you'll be hitting the springs. So, do the math yourself for positive offset wheels:

 

Backspace = (offset in mm / 25.4) + (wheel width / 2)

 

16x7+38 = 4.99" of backspace

16x8+38 = 5.49" of backspace

 

16x7+13 = 4.01" of backspace

16x8+14 = 4.55" of backspace

[Topher]

 

Here's how a 17X7/17X8 +38 offset wheel fits with a 1.5" spacer and a 1" drop if it helps you any.

 

 

This helps a lot. Most of the Wats I see in google image are on cars with over-fenders, something I like, but will not do to my Z.

 

Seeing as how the width and the offset and the spacers that you picked are nearly identical to what I would run, that certainly comforts me.

 

As it appears the wheels/tires look pretty flush on the fender.

[Topher]

Offest is only useful in calculation backspace. For a 240Z running stock diameter springs you can run a wheel with 3.5" to 3.75" of backspace - assuming your tire sidewall is vertical and not bowed out (tread width wider then rim width). At 4" there's a good change you'll be hitting the springs. So, do the math yourself for positive offset wheels:

 

Backspace = (offset in mm / 25.4) + (wheel width / 2)

 

16x7+38 = 4.99" of backspace

16x8+38 = 5.49" of backspace

 

16x7+13 = 4.01" of backspace

16x8+14 = 4.55" of backspace

 

Thank you!

 

Now I see why people are saying, 1.5" spacers. But I guess I wouldn't really need 1.5 in the front and could rather get by with a 1.25 or a 1.

 

Right?

 

 

Again, many thanks.

[S30TRBO]

Any suggestions on tire size?

 

225/50 front?

255/50 rear?

 

You can run either size. With the 255 they will stick outside of the fender unless you flare it. Or you can run 225/50/16 all the way around. If you are looking for the staggard look then 205/55/16 front 225/50/16 rear.

 

Here is my 240Z with 225/50/16 all around on 16x8.5 -6 Type R Watanabe's:

 

I had 245/45/16 rear on 16x9.5 -19 Type R Watanabe's here is what they look like on GC coil overs:

 

 

 

 

Good Luck!

[Topher]

Cool Joe!

[veritech-z]

JohnC, my experience (such as it is...) with wheel fitment has been that you can fit closer to 4.5" of backspace before it becomes a problem on a stock strut. My 17X8 +38 offset wheels fit with a 1.5" spacer(38.1mm-making for essentially 0 offset and 4.5" of backspacing) and a 255/40 tire without rubbing. I see you specified a 240z, would the fact I've got a 280z make a difference? Also,I'm sure you know already, but I think it's important to note in the backspace equation that there is a difference between advertised wheel width and actual measured wheel width since they typically measure from the inside of the bead to the inside of the bead for that.

 

topher, you may be able to get away with a 1" spacer in the front, but they are typically sold in sets, so why not just get them all the same? there shouldn't be price difference between those two sizes.

[johnc]

A lot depends on the tire installed on the rim and the particular car everyting is installed on. On my 1970 240Z, 15 x 7 rims with 3.5" of backspace and 225/50-15 street tires had about 1" of clearance to a set of 2.5" coilovers. With 225/50-15 Hoosier A3S03s on 15 x 8 rims with 4" of backspace I had about 1/16" of clearance to those same coilovers.

 

Section width across the same tire size varies by as much as 1" when installed on identical width rims. I know its not supposed to be that way, but in the real world there are a lot of variances.

[johnc]

topher, you may be able to get away with a 1" spacer in the front, but they are typically sold in sets, so why not just get them all the same?

 

From a handling perspective a wider front track is better. If you can run 1.25" wide spacers on front a 1" wide spacers on the rear, the car will turn-in and put power down better.

[veritech-z]

A lot depends on the tire installed on the rim and the particular car everyting is installed on.

I can vouch for that, prior to using the Falken Ziex512's I'm using now, I had Bridgestone Potenzas. The Falkens are almost straight up and down, but the Potenzas hung way out over the side.

[Topher]

UPDATE

 

 

All right. I think I am going to order the Watanabe RS8 today.

 

Figuring, 16x7+13 = 4.01" of backspace

16x8+14 = 4.55" of backspace

 

I need to space the rear out a bit ~.5" and the front ~.25

 

For tires, I was going to do the Hankook Ventus R-S2 Z212, 225/50/16 in the front.

 

And the same tires, but in 245/45/16 in the rear.

 

Reason for sizing, putting 225s would be a little stretch on a 8in wide wheel.

 

Anyone see anything they would get nervous about?

[johnc]

Reason for sizing, putting 225s would be a little stretch on a 8in wide wheel.

 

225s on an 8" wheel is perfect and that's what I used to race on when my 240Z was running in BSP.