Hardrace subframe bushing stiffeners

pbonsalb · 09-12-2022, 09:00 PM

Installed Hardrace aluminum rear subframe bushing stiffeners. There are round plates with protrusions that fill the small voids in the top or bottom of the stock subframe bushings. I have changed subframe bushings to stiffer ones on other cars (E36 M3, E90 M3) but none were available for the F90 M5. The Hardrace plates fit on top of the front bushings and on the bottom of the rears. They don’t tell you where they go or how to install. The only disconnect you need to do are the rear ride height sensor harnesses. Then you can lower maybe 2” to do the fronts. Support the subframe, but without the raised cone washers under the bushings, you have about 2” play in the bolts while still having 6-8 threads on the bolt engaged. While I figured all plates would go in the bottom and this would be easy and not require any lowering it e def up not being as bad as it could have been.

Will give a review later. Was it worth the $225?

Dinan rear tow link kit is coming soon. Have Dinan monoballs, comp motor mounts, H&R M5 springs and Titan7 TS5 lighter wheels now.

PDOT · 09-13-2022, 10:34 AM

Quote:

Originally Posted by pbonsalb

Installed Hardrace aluminum rear subframe bushing stiffeners. There are round plates with protrusions that fill the small voids in the top or bottom of the stock subframe bushings. I have changed subframe bushings to stiffer ones on other cars (E36 M3, E90 M3) but none were available for the F90 M5. The Hardrace plates fit on top of the front bushings and on the bottom of the rears. They don’t tell you where they go or how to install. The only disconnect you need to do are the rear ride height sensor harnesses. Then you can lower maybe 2” to do the fronts. Support the subframe, but without the raised cone washers under the bushings, you have about 2” play in the bolts while still having 6-8 threads on the bolt engaged. While I figured all plates would go in the bottom and this would be easy and not require any lowering it e def up not being as bad as it could have been.

Will give a review later. Was it worth the $225?

Dinan rear tow link kit is coming soon. Have Dinan monoballs, comp motor mounts, H&R M5 springs and Titan7 TS5 lighter wheels now.

Any difference with the monoballs?

pbonsalb · 09-13-2022, 11:09 AM

Monoballs help a little. You can feel the front end is a little tighter in a higher speed or sharper turn since there is less rubber. I would not say it is dramatic like some say, but maybe those people feel more than me. There is little to no downside — maybe if you hit a railroad track or similar obstacle with both front wheels you will feel a little more bump. My thought is all these little things take enough play out of the suspension for the total to be worthwhile. I am not trying to slam the car so travel is minimal or to remove all the compliance. Maybe I should have just bought a competition, after all…

PDOT · 09-13-2022, 12:31 PM

Quote:

Originally Posted by pbonsalb

Monoballs help a little. You can feel the front end is a little tighter in a higher speed or sharper turn since there is less rubber. I would not say it is dramatic like some say, but maybe those people feel more than me. There is little to no downside — maybe if you hit a railroad track or similar obstacle with both front wheels you will feel a little more bump. My thought is all these little things take enough play out of the suspension for the total to be worthwhile. I am not trying to slam the car so travel is minimal or to remove all the compliance. Maybe I should have just bought a competition, after all…

I have a comp and looking to make some moves over the winter, trying to see what stuff worth it. Maybe a HAS but still on the fence.

pbonsalb · 09-13-2022, 01:03 PM

I have H&R M5 springs, which are stiffer than stock, and would not go any stiffer or any lower. I don’t know that the H&R M550ix springs are any stiffer than stock springs. The people who install them are mostly interested in the cosmetic effect of reducing gap between the tire and fender arch rather than handling.

The only advantage HAS would have for me is preserving suspension travel but I am not sure whether it actually does that since the strut internals remain the same length inside. Or maybe I don’t understand Ju well enough. I have read a little about “packers” and they do look interesting to me. Maybe it all comes together in a way that has advantages over just springs when the struts themselves don’t change. I have coilovers on another car and never really adjust them - it seems like a great option but is enough of a pain to do that you will just find the height you want and leave it.

m5 guy · 09-13-2022, 05:49 PM

Is it wrong I kind of want to get all the parts they make? lol Going to have to look into them more, thanks!

As for the dinan monoballs I've been considering switching to the carbahn ones, but still need to talk to carbahn first. Looking at online pics the bushings look quite different with the carbahn ones looking more serious to me.

What's your take on the two?

pbonsalb · 09-13-2022, 06:08 PM

I don’t know that you need all the parts they make. Some of the chassis braces probably won’t fit the M5 or are already there in a similar form. The front wishbones might be good if you need to adjust camber but I have 1.5 degrees negative stock and that is OK for my Street car. Maybe I would try 2.0 but I won’t spend $800 for half a degree.

No one would notice any difference in performance between the Dinan and Carbahn front monoballs. If you have one changing to the other would be a waste of time and money.

Maverik259 · 09-23-2022, 10:16 AM

Quote:

Originally Posted by m5 guy

Is it wrong I kind of want to get all the parts they make? lol Going to have to look into them more, thanks!

As for the dinan monoballs I've been considering switching to the carbahn ones, but still need to talk to carbahn first. Looking at online pics the bushings look quite different with the carbahn ones looking more serious to me.

What's your take on the two?

had the carbahn installed a couple weeks ago and experience the same effect everyone talks about. Don't think they'll feel any different than the dinan. just designed differently. i do experience a bit more "rattle" when going over certain imperfections quickly but overall the car feels more responsive in the front.

jake169 · 03-28-2023, 10:41 AM

pbonsalb any update on how the car feels now, after driving it around for a bit

pbonsalb · 03-28-2023, 11:19 AM

I have had my all seasons on since November. Will put on the summer wheels this weekend. Since installing the bushing limiters, I also added the Dinan rear arms kit. I think all I will be able to say is that the wiggle is gone or reduced, but not how much of the benefit is attributable to each part.

09-12-2022, 09:00 PM	#1
pbonsalb Lieutenant General 5230 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	Hardrace subframe bushing stiffeners Installed Hardrace aluminum rear subframe bushing stiffeners. There are round plates with protrusions that fill the small voids in the top or bottom of the stock subframe bushings. I have changed subframe bushings to stiffer ones on other cars (E36 M3, E90 M3) but none were available for the F90 M5. The Hardrace plates fit on top of the front bushings and on the bottom of the rears. They don’t tell you where they go or how to install. The only disconnect you need to do are the rear ride height sensor harnesses. Then you can lower maybe 2” to do the fronts. Support the subframe, but without the raised cone washers under the bushings, you have about 2” play in the bolts while still having 6-8 threads on the bolt engaged. While I figured all plates would go in the bottom and this would be easy and not require any lowering it e def up not being as bad as it could have been. Will give a review later. Was it worth the $225? Dinan rear tow link kit is coming soon. Have Dinan monoballs, comp motor mounts, H&R M5 springs and Titan7 TS5 lighter wheels now.
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09-13-2022, 11:09 AM	#3
pbonsalb Lieutenant General 5230 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	Monoballs help a little. You can feel the front end is a little tighter in a higher speed or sharper turn since there is less rubber. I would not say it is dramatic like some say, but maybe those people feel more than me. There is little to no downside — maybe if you hit a railroad track or similar obstacle with both front wheels you will feel a little more bump. My thought is all these little things take enough play out of the suspension for the total to be worthwhile. I am not trying to slam the car so travel is minimal or to remove all the compliance. Maybe I should have just bought a competition, after all…
	Appreciate 1 afo818254.50 Quote

09-13-2022, 01:03 PM	#5
pbonsalb Lieutenant General 5230 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	I have H&R M5 springs, which are stiffer than stock, and would not go any stiffer or any lower. I don’t know that the H&R M550ix springs are any stiffer than stock springs. The people who install them are mostly interested in the cosmetic effect of reducing gap between the tire and fender arch rather than handling. The only advantage HAS would have for me is preserving suspension travel but I am not sure whether it actually does that since the strut internals remain the same length inside. Or maybe I don’t understand Ju well enough. I have read a little about “packers” and they do look interesting to me. Maybe it all comes together in a way that has advantages over just springs when the struts themselves don’t change. I have coilovers on another car and never really adjust them - it seems like a great option but is enough of a pain to do that you will just find the height you want and leave it.
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09-13-2022, 05:49 PM	#6
m5 guy Brigadier General 1692 Rep 3,200 Posts Drives: 2020 M5 Comp Join Date: Apr 2012 Location: Hawaii iTrader: (14)	Is it wrong I kind of want to get all the parts they make? lol Going to have to look into them more, thanks! As for the dinan monoballs I've been considering switching to the carbahn ones, but still need to talk to carbahn first. Looking at online pics the bushings look quite different with the carbahn ones looking more serious to me. What's your take on the two? __________________ 2020 F90 M5 Comp Oxford Green Metallic II-Aragon JOURNAL 2016 F10 M5 Space Gray-Black SOLD 2012 E70 X5M Monte Carlo Blue-Silverstone SOLD 2001 E46 M3 Oxford Green Metallic II-Cinnamon SOLD
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09-13-2022, 06:08 PM	#7
pbonsalb Lieutenant General 5230 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	I don’t know that you need all the parts they make. Some of the chassis braces probably won’t fit the M5 or are already there in a similar form. The front wishbones might be good if you need to adjust camber but I have 1.5 degrees negative stock and that is OK for my Street car. Maybe I would try 2.0 but I won’t spend $800 for half a degree. No one would notice any difference in performance between the Dinan and Carbahn front monoballs. If you have one changing to the other would be a waste of time and money.
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03-28-2023, 10:41 AM	#9
jake169 Private First Class 29 Rep 182 Posts Drives: 2011 35is Join Date: Apr 2013 Location: new jersey iTrader: (0)	pbonsalb any update on how the car feels now, after driving it around for a bit
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03-28-2023, 11:19 AM	#10
pbonsalb Lieutenant General 5230 Rep 10,614 Posts Drives: 18 F90 M5, 99 E36 M3 Turbo Join Date: Feb 2011 Location: New England iTrader: (4)	I have had my all seasons on since November. Will put on the summer wheels this weekend. Since installing the bushing limiters, I also added the Dinan rear arms kit. I think all I will be able to say is that the wiggle is gone or reduced, but not how much of the benefit is attributable to each part.
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