Wheel Offset Calculator Tool for Excel

[Tony D]

Hey fellow GTO lovers, I have a spreadsheet that calculates where your wheels will be positioned on your car for different widths and offsets. Hope it will help us all when making choices on wheels (not that there are many)

BTW Our stock wheels are 8 inches wide and the offset is 48 mm.

Hope it helps, here is the link

www.geocities.com/nismotony/index.html

[jdo6696]

thanks man.

[tmoneyr007]

That's gonna be awesome but it needs some permanent, "this will rub on the inside line" or "this will make you have to roll your fenders line"

Know what I mean?

[nathang]

This is just what I've been wanting to see. Kudos Tony D. !

Now, what needs to be done, please, over time I'd like to see the spreadsheet
populated with all of the popular sizes and brands discussed here,
to use as a reference.

What we need to know is what's the absolute depth limit in back of the hub,
and what's the maximum extension limit in front of the hub, for each wheel diameter.

Especially with comments,
Was it possible to get an offset to fit by rolling or grinding the fender lip?
Did it fit before lowering but rub after?
Was there anything in the back that could be hammered on or ground down?

My perspective is, if I didn't have to roll or grind the fenders in back,
I didn't buy enough wheel.

Ideally, tire brands and sizes would be included too, since at the limit,
a rounded shoulder that fits vs a squared shoulder that doesn't will make this
data compilation much more useful.

Another table, if someone has an idea about a way to set it up,
is a reported failures record. Specifically, I've had problems in the
past with light cast wheels on heavy performance cars getting bent
way too often. It seems more problematic on some wheels types
and structures than others.

I know I'll never again buy the last known set of a great looking wheel.
I bent both rims on one side within a month.

I came to the conclusion that a wheel brand that says "light" is not for me,
at least not on performance cars approaching 2 tons.
I'll take the ones that say "heavy."

I'm coming closer to thinking the price for forged rims might be worth it.

[deton8r]

Thanks! This is very useful. Version 1.1 should add the inner and outer boundaries.

[BlueFlyingGoat]

Thanks! This is very useful. Version 1.1 should add the inner and outer boundaries.

+1:judge: With GTO's suffering from the dreaded strut rub up front and the fender lip issues in the rear, we'll take all the help we can get!:thumbs:

[nixapatfan]

Not bad. Another suggestion.

Can you add cells to show the difference in clearance on the inside and outside from A to B

[Havoc]

Hey fellow GTO lovers, I have a spreadsheet that calculates where your wheels will be positioned on your car for different widths and offsets. Hope it will help us all when making choices on wheels (not that there are many)

BTW Our stock wheels are 8 inches wide and the offset is 48 mm.

Hope it helps, here is the link

www.geocities.com/nismotony/index.html

Nice work, but there are a quite few of these online.. example: http://www.1010tires.com/WheelOffsetCalculator.asp

[SlotCar]

This is too cool, thanks for the program.

I will have to give our "spreedsheet" guy at work a hard time.... his never look this good.

[nathang]

For my purposes, the best value to this thread would be to be able to reference the limits of contact front and rear with different rim diameters. Not just tech data, but a fitment somebody is able to live with. I'm expecting to need to roll or grind the inner fender lips, particularly in the rear, you can't expect the most traction w/o that step, IMHO.

From the "show me your wheels" thread I have recorded the best info I can find for 18" rims

9.5x18 ET45 running 275/35/18 rear
8x18 ET40 running 245/40/18 rear

That would pretty much do it for me, if I could find 17" rims that would allow the same fitment. I want to find if those same or similar offsets will work on 17" rims, as I have had trouble repeatedly bending 18" rims in the past.

I don't want to assume 9.5 wheels with 45 offset will also fit on the rear with 17" wheels, because the Mercedes I used to hot-shoe could fit more backspacing in the rear end in 18" or 19" wheel diameters than in 17" because of a reverse slope on the rear wheelwell's bulkhead, it took some serious hammer massaging on that bulkhead to get max results with 17" rims. Still couldn't lift the car except from under the axle to keep compression on the suspension.

Anybody else compiling this same info I'd like to hear your findings.

[Tony D]

Ok, I put up another one for choosing tire size. Here it is

www.geocities.com/nismotony/index.html