Installed MP HAS and rear is high even on max lowest thread

jshahm · 11-08-2020, 05:04 PM

I installed the MP HAS and the rear looks even higher than stock somehow despite being on the lowest thread. It's about a two finger gap between the top of tire and the wheel well. What gives?

18x11 +44 with 315/30 tire

knightarmor · 11-08-2020, 06:37 PM

Take pictures of the install, front and rear.

horsepower_and_hounds · 11-09-2020, 03:35 AM

whoooooo....... something is wrong there

Megabass · 11-09-2020, 07:39 AM

This is mine right after install. There was another member who had the dealer install and they left the stock bump stops in.

TopJimmy · 11-09-2020, 08:06 AM

I think the problem is running those 18in wheels and tire combo. Your 315/30/18 are only 647mm (25.4in) diameter, which is an inch shorter than normal (26.3in). That's one problem to fix...
The 305/30/19 is 26.2in tall.
Your 315//18 is 12.5in wide and the 305//19 is 12.3in wide.

Also, HAS needs to settle down. Make sure your rear spring adjusters look "all the way up" (but NOT touching, hair gap is good enough, otherwise it can get stuck to adjust later). Go to a place with speed bumps or humps (airport) and do ride overs to help your springs settle. After about 10 laps I settled a bit.

jshahm · 11-09-2020, 05:33 PM

Quote:

Originally Posted by TopJimmy

I think the problem is running those 18in wheels and tire combo. Your 315/30/18 are only 647mm (25.4in) diameter, which is an inch shorter than normal (26.3in). That's one problem to fix...
The 305/30/19 is 26.2in tall.
Your 315//18 is 12.5in wide and the 305//19 is 12.3in wide.

Also, HAS needs to settle down. Make sure your rear spring adjusters look "all the way up" (but NOT touching, hair gap is good enough, otherwise it can get stuck to adjust later). Go to a place with speed bumps or humps (airport) and do ride overs to help your springs settle. After about 10 laps I settled a bit.

the wheel/tire setup makes sense, but i've seen 305/35/18's on MP HAS that look significantly lower. i suppose that higher aspect ratio and shorter width really make a big diff.

TopJimmy, your name is well-deserved. thanks!

TopJimmy · 11-09-2020, 05:52 PM

Toyo Proxies TQ drag radial in 315/35/19 is made for an 11in wheel and is 26.8in tall by 12.5in wide (section).

Toyo Proxies R888R compound tire in 305/35/19 is made for an 11in wheel and is 26.4in tall by 12.3in wide (section).

Toyo Proxies RR compound radial in 305/35/19 is made for an 11in wheel and is 26.4 in tall by 12.3in wide (section).

knightarmor · 11-09-2020, 10:12 PM

Pics of the rear suspension? Also taking measurement at the rear per the MPHAS instructions would help. That looks like more than a tire size issue.

m3elmo · 11-09-2020, 10:44 PM

^^^^ the tire size you have would be good for 19" tire, but you're using an 18". But I'm trying to imagine your picture with 0.5" more going to the top, and it still doesn't seem low enough.

DanMpower · 11-10-2020, 02:11 AM

You have the rear spring/helper spring installed upside down.

It should look like this.

11-08-2020, 05:04 PM	#1
jshahm First Lieutenant 48 Rep 372 Posts Drives: 2015 M4, 1998 ZCP Toyota Camry Join Date: Jan 2019 Location: Los Angeles, CA iTrader: (1) Garage List 2015 BMW M4 [0.00]	I installed the MP HAS and the rear looks even higher than stock somehow despite being on the lowest thread. It's about a two finger gap between the top of tire and the wheel well. What gives? 18x11 +44 with 315/30 tire Attached Images
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11-08-2020, 06:37 PM	#2
knightarmor Lieutenant Colonel 855 Rep 1,550 Posts Drives: 2017 M3 Join Date: Jan 2015 Location: Washington iTrader: (2)	Take pictures of the install, front and rear.
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11-09-2020, 03:35 AM	#3
horsepower_and_hounds Brigadier General 1836 Rep 4,203 Posts Drives: BMW Join Date: Aug 2012 Location: USA iTrader: (9)	whoooooo....... something is wrong there
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11-09-2020, 07:39 AM	#4
Megabass Second Lieutenant 168 Rep 259 Posts Drives: 2019 M4 CP Join Date: Oct 2018 Location: Copperopolis iTrader: (0)	This is mine right after install. There was another member who had the dealer install and they left the stock bump stops in. Attached Images
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11-09-2020, 08:06 AM	#5
TopJimmy Major General 5450 Rep 5,143 Posts Drives: 2023 M3 Comp xDrive Join Date: Jul 2019 Location: Chester County, PA iTrader: (5)	I think the problem is running those 18in wheels and tire combo. Your 315/30/18 are only 647mm (25.4in) diameter, which is an inch shorter than normal (26.3in). That's one problem to fix... The 305/30/19 is 26.2in tall. Your 315//18 is 12.5in wide and the 305//19 is 12.3in wide. Also, HAS needs to settle down. Make sure your rear spring adjusters look "all the way up" (but NOT touching, hair gap is good enough, otherwise it can get stuck to adjust later). Go to a place with speed bumps or humps (airport) and do ride overs to help your springs settle. After about 10 laps I settled a bit. __________________ '18 F80 Base 6MT \| '19 F82 Exec DCT \| '18 F82 Comp Exec DCT \| '23 G80cx
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11-09-2020, 05:52 PM	#7
TopJimmy Major General 5450 Rep 5,143 Posts Drives: 2023 M3 Comp xDrive Join Date: Jul 2019 Location: Chester County, PA iTrader: (5)	Toyo Proxies TQ drag radial in 315/35/19 is made for an 11in wheel and is 26.8in tall by 12.5in wide (section). Toyo Proxies R888R compound tire in 305/35/19 is made for an 11in wheel and is 26.4in tall by 12.3in wide (section). Toyo Proxies RR compound radial in 305/35/19 is made for an 11in wheel and is 26.4 in tall by 12.3in wide (section). __________________ '18 F80 Base 6MT \| '19 F82 Exec DCT \| '18 F82 Comp Exec DCT \| '23 G80cx
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11-09-2020, 10:12 PM	#8
knightarmor Lieutenant Colonel 855 Rep 1,550 Posts Drives: 2017 M3 Join Date: Jan 2015 Location: Washington iTrader: (2)	Pics of the rear suspension? Also taking measurement at the rear per the MPHAS instructions would help. That looks like more than a tire size issue.
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11-09-2020, 10:44 PM	#9
m3elmo Private First Class 50 Rep 117 Posts Drives: F80 M3 Join Date: Oct 2020 Location: Bay Area, CA iTrader: (0)	^^^^ the tire size you have would be good for 19" tire, but you're using an 18". But I'm trying to imagine your picture with 0.5" more going to the top, and it still doesn't seem low enough. __________________ Danny Bay Area, CA
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11-10-2020, 02:11 AM	#10
DanMpower Colonel 3230 Rep 2,159 Posts Drives: BMW M3s and a Red VW Join Date: Feb 2018 Location: Southern CA iTrader: (28)	You have the rear spring/helper spring installed upside down. It should look like this.
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