Accurately measuring ride height

[bavarian3]

Curious to hear how others prefer to get an accurate measurement of ride height?

I used to simply throw a measuring tape on the center of the center cap then measure to the fender lip. Now my new wheels are recessed at the hubs much more than stock wheels so I can't get an accurate measurement with this method.

To try and solve this, I measured the wheel daimeter lip to lip, then divided by 2. I then measured from bottom wheel lip to fender, then subtracted the half wheel diameter. I don't see why this wouldn't be perfectly accurate, but my results are a little less than expected.

What ya all think?

[George Hill]

To try and solve this, I measured the wheel daimeter lip to lip, then divided by 2. I then measured from bottom wheel lip to fender, then subtracted the half wheel diameter. I don't see why this wouldn't be perfectly accurate, but my results are a little less than expected.

That is how BMW does it, bottom of the wheel lip straight up to the fender.

[bigjae46]

I've been toying with the idea of designing a tool that fits into the wheel bore and provides a measurement point exactly in the middle of the wheel. This would make setting up my alignment strings much faster and more accurate. Could also be used for ride height measurements.

[bavarian3]

That is how BMW does it, bottom of the wheel lip straight up to the fender.

right but I think this requires the use of stock wheels? wondering if lip sizes have an effect, but that should be what measuring the actual wheel solves.

[bavarian3]

I've been toying with the idea of designing a tool that fits into the wheel bore and provides a measurement point exactly in the middle of the wheel. This would make setting up my alignment strings much faster and more accurate. Could also be used for ride height measurements.

please do!

[cobra]

I think your method works just fine.

[Stilt]

I've been toying with the idea of designing a tool that fits into the wheel bore and provides a measurement point exactly in the middle of the wheel. This would make setting up my alignment strings much faster and more accurate. Could also be used for ride height measurements.

It's just a 3D-printed puck, the diameter of the center bore of the wheel, with a dowel-esque bar protruding out horizontally to attach a string—a center cap but with a way to attach the string to it in a repeatable manner.

[George Hill]

right but I think this requires the use of stock wheels?

BMW has specs for each size of wheel that is standard for a car. But its just a mathematical equation, just like you are doing to find the difference.

When I compare vehicles and they have different diameter wheels I just measure and calculate to add or subtract the difference in radius.

TLDR, your way is just fine.

[bavarian3]

I think your method works just fine.

BMW has specs for each size of wheel that is standard for a car. But its just a mathematical equation, just like you are doing to find the difference.

When I compare vehicles and they have different diameter wheels I just measure and calculate to add or subtract the difference in radius.

TLDR, your way is just fine.

Appreciate it guys!

[Tbonem3]

It's about consistency similar to comp test and dyno #s

[elbert]

It's about consistency

Exactly. IMO using the bottom edge of the wheel is the most consistent

What I wonder is how symmetrical are my fenders and quarter panels...

[D-O]

TCK advises using the bottom of the rocker. Not as easily repeatable as it sounds.

[bigjae46]

It's just a 3D-printed puck, the diameter of the center bore of the wheel, with a dowel-esque bar protruding out horizontally to attach a string—a center cap but with a way to attach the string to it in a repeatable manner.

The protrusion would need to account for camber...I have to think about this more. But it could be an awesome tool!

[eacmen]

TCK advises using the bottom of the rocker. Not as easily repeatable as it sounds.

I like this method personally. But you need to pick points on the rocker that won't deform like the jack points do.

[eacmen]

For quick checks using the wheel center cap I made this tool that will give me an accurate plane to place the tape measure on to make measurements more repeatable. Its not the perfect thing but better than nothing. You can find the model here:

https://thangs.com/designer/eacmen/3d-model/BMW%20Ride%20Height%20Measuring%20Tool-1218431?source=All+Files