Stock ride height, F80 M3? And, AirLift-like helper air bags?

Bill Cool · 09-05-2022, 12:28 PM

I just purchased a used, "stock except for 437M wheels" 2018 M3. While static, I notice the rear end visually appears lower than the front. Searching threads here, and some stock Google images, that appears to be largely factory...but I'd like to verify that these measurements are accurate, since the rear tires look almost tucked especially compared to the front end (photos at bottom of post).

The car is on 255/35ZR19 front and 275/35ZR19 rear.

Driver
ground to fender - 27-3/8", or ~695mm
bottom of rim to fender - 25-1/4", or ~641

Passenger front
ground to fender - 27-1/8", or ~689mm. I hope variation L to R is due to my poor tape measure skills
bottom of rim to fender - 25-1/8", or ~639

Driver rear
ground to fender - 26-1/2", or ~673
bottom of rim to fender - 23-3/4", or ~603mm

Passenger front
ground to fender - 26-1/4", or ~ 667mm. I imagine variation L to R is due to my poor tape measure skills
bottom of rim to fender - 23-3/4", or ~603mm

Secondly, I've found multiple full-replacement air suspensions, but does anyone know of a M3-compatible helper air bag kit like the AirLift 1000? I am not looking for adjustable suspension; just for a little help preventing squat while towing.

Sephrr · 09-05-2022, 08:45 PM

My car is stock with suspension except it has brand new oem springs on it. Back tire has great fitment but still has good wheel gap in front. Sometimes it even looks lowered only in the rear at some angles

Bill Cool · 09-06-2022, 01:58 PM

Quote:

Originally Posted by Sephrr

My car is stock with suspension except it has brand new oem springs on it. Back tire has great fitment but still has good wheel gap in front. Sometimes it even looks lowered only in the rear at some angles

Thanks for the photos! Could I trouble you to please take and post similar measurements at each corner? Or at least front and rear on one side?

Also, why did you install a new stock springs, and after how many miles?

RugbyBro · 09-06-2022, 02:08 PM

The rear wheel arch on F80s physically sits lower than F82s even though the ride height is the same:

Bill Cool · 09-06-2022, 02:31 PM

Interesting! Do you happen to have the data on what F80 ride height should be, stock, considering the wheel well location?

If these are the proper instructions for the MP HAS, and on the assumption that BMW's recommended height for MP HAS is the same as stock (though I'm not sure whether that's a safe assumption), then my front is too high and my rear is too low (pages 7-8).

If I were to assume stock ZCP height is also applicable to a regular F80 (is that true?), then my front is spot on and my rear, again, is too low.

Sephrr · 09-06-2022, 08:33 PM

Quote:

Originally Posted by Bill Cool

Quote:

Originally Posted by Sephrr

My car is stock with suspension except it has brand new oem springs on it. Back tire has great fitment but still has good wheel gap in front. Sometimes it even looks lowered only in the rear at some angles

Thanks for the photos! Could I trouble you to please take and post similar measurements at each corner? Or at least front and rear on one side?

Also, why did you install a new stock springs, and after how many miles?

I can measure tomorrow. Bmw put them on before I purchased the car since it was on lowering springs before and they put it back to factory

Sephrr · 09-07-2022, 03:08 PM

Lf ground to fender ~27 3/8"
Bottom lip to fender ~25"
Lr ground to fender ~26 7/8"
Bottom lip to fender ~24 1-4"
Rr ground to fender ~26 5/8"
Bottom lip to fender 23 15/16"
Rf ground to fender ~27 3/8"
Bottom lip to fender ~25"

swagon · 09-10-2022, 07:27 AM

Quote:

Originally Posted by Bill Cool

I just purchased a used, "stock except for 437M wheels" 2018 M3. While static, I notice the rear end visually appears lower than the front. Searching threads here, and some stock Google images, that appears to be largely factory...but I'd like to verify that these measurements are accurate, since the rear tires look almost tucked especially compared to the front end (photos at bottom of post).

This has been a thing since forever and people still don't understand it.

BMWs have a larger rear wheel arch than in the front. This makes people think it's got rake to it - meanwhile the side skirt, if you look at it, is mostly level with the ground.

If you want totally even wheel gap, you will end up with rather great positive rake which has its implications on driving dynamics and weight distribution.

Recommended ride height with MP HAS is not the same as stock.

You're also measuring ground to fender whilst the MP HAS document clearly shows that BMW measures alloy wheel bottom to fender.

Not sure what you want to tow with your car, but I can think of thousands of better solutions to your problem than installing air bags on this fine driving machine for the sake of towing shit with it.

Bill Cool · 09-11-2022, 01:48 PM

Quote:

Originally Posted by Sephrr

Lf ground to fender ~27 3/8"
Bottom lip to fender ~25"
Lr ground to fender ~26 7/8"
Bottom lip to fender ~24 1-4"
Rr ground to fender ~26 5/8"
Bottom lip to fender 23 15/16"
Rf ground to fender ~27 3/8"
Bottom lip to fender ~25"

Thank you!! So my front end seems pretty accurate, passenger rear almost accurate, and driver rear off by ~ 1/2". I'll need to look into whether the stock suspension is adjustable...

Quote: