[zero21]

Originally Posted by Tag

The HAS kit doesn't make it stiffer.

Pleasantly surprised to learn that several cars have been modified with different HAS kits and everyone is reporting factory ride quality.

I talked to someone this morning at Cars and Coffee with an MSS kit dropped nearly all the way on his M4 and he's 68 and says it's factory ride quality. Loved it.

I think we're all pretty safe with a modest drop of 10-25mm.

[Tag]

Originally Posted by zero21

Pleasantly surprised to learn that several cars have been modified with different HAS kits and everyone is reporting factory ride quality.

I talked to someone this morning at Cars and Coffee with an MSS kit dropped nearly all the way on his M4 and he's 68 and says it's factory ride quality. Loved it.

I think we're all pretty safe with a modest drop of 10-25mm.

Yup, I was just putting this together to help people understand what a HAS kit does.

In this illustration I'm using the front struts. The rear uses shocks but the principal is the same. The HAS kit lowers the car in a couple of ways. The spring perch is replaced with an adjustable one that sits lower on the OEM strut. The replacement springs that come with the kit are also shorter. To make up for slightly shorter springs any quality HAS kit will also come with shorter bump stops. If you've ever heard of people saying their ride sucks and they are always riding on their bump stops that's what they mean. There isn't enough compression range, and they are always on the bump stops. Think of bump stops as just another spring, 'riding it' increases the spring rate which results in a stiffer ride. That's why you always hear me preaching that getting a 'quality' HAS kit that comes with shorter ones is a must.

***There are always caveats when modding. Because the HAS kit is adjustable, meaning the spring perch lets you raise and lower the car you can go lower than the recommended setup. The M Performance HAS kit lowering range is 5-20mm when compared to stock. BMW recommends 10mm, but at some point past 10mm you will have less compression than the stock suspension before you hit the bump stops. Some people might be OK with this (like me ), others might not. It's at your discretion but even if you want a 100% stock ride you can lower the G87 at least 10mm without any impact to the ride quality. The beauty of a HAS kit is you can play with it. If it's too low and you are not happy raise it until you are. It'll still be lower than stock and since you are lowering the entire cars center of gravity it will handle better than stock.

EXAMPLE (These are generic struts for illustration purposes only)

[Slick1984]

Originally Posted by Tag

Yup, I was just putting this together to help people understand what a HAS kit does.

In this illustration I'm using the front struts. The rear uses shocks but the principal is the same. The HAS kit lowers the car in a couple of ways. The spring perch is replaced with an adjustable one that sits lower on the OEM strut. The replacement springs that come with the kit are also shorter. To make up for slightly shorter springs any quality HAS kit will also come with shorter bump stops. If you've ever heard of people saying their ride sucks and they are always riding on their bump stops that's what they mean. There isn't enough compression range, and they are always on the bump stops. Think of bump stops as just another spring, 'riding it' increases the spring rate which results in a stiffer ride. That's why you always hear me preaching that getting a 'quality' HAS kit that comes with shorter ones is a must.

***There are always caveats when modding. Because the HAS kit is adjustable, meaning the spring perch lets you raise and lower the car you can go lower than the recommended setup. The M Performance HAS kit lowering range is 5-20mm when compared to stock. BMW recommends 10mm, but at some point past 10mm you will have less compression than the stock suspension before you hit the bump stops. Some people might be OK with this (like me ), others might not. It's at your discretion but even if you want a 100% stock ride you can lower the G87 at least 10mm without any impact to the ride quality. The beauty of a HAS kit is you can play with it. If it's too low and you [...]

Amazing write-up!

[cmgbk75]

Originally Posted by Tag

Yup, I was just putting this together to help people understand what a HAS kit does.

In this illustration I'm using the front struts. The rear uses shocks but the principal is the same. The HAS kit lowers the car in a couple of ways. The spring perch is replaced with an adjustable one that sits lower on the OEM strut. The replacement springs that come with the kit are also shorter. To make up for slightly shorter springs any quality HAS kit will also come with shorter bump stops. If you've ever heard of people saying their ride sucks and they are always riding on their bump stops that's what they mean. There isn't enough compression range, and they are always on the bump stops. Think of bump stops as just another spring, 'riding it' increases the spring rate which results in a stiffer ride. That's why you always hear me preaching that getting a 'quality' HAS kit that comes with shorter ones is a must.

***There are always caveats when modding. Because the HAS kit is adjustable, meaning the spring perch lets you raise and lower the car you can go lower than the recommended setup. The M Performance HAS kit lowering range is 5-20mm when compared to stock. BMW recommends 10mm, but at some point past 10mm you will have less compression than the stock suspension before you hit the bump stops. Some people might be OK with this (like me ), others might not. It's at your discretion but even if you want a 100% stock ride you can lower the G87 at least 10mm without any impact to the ride quality. The beauty of a HAS kit is you can play with it. If it's too low and you [...]

Best explanation I’ve come across, especially regarding ride quality. Has me even more confident in my decision to have it added at the Port and the benefits that come with it (warranty, Monorey, experienced installers). Thanks.

[VIERsr]

Does anyone know the spring rate of OEM springs and M Performance springs?

[M Division]

Originally Posted by zero21

Pleasantly surprised to learn that several cars have been modified with different HAS kits and everyone is reporting factory ride quality.

I talked to someone this morning at Cars and Coffee with an MSS kit dropped nearly all the way on his M4 and he's 68 and says it's factory ride quality. Loved it.

I think we're all pretty safe with a modest drop of 10-25mm.

Interesting considering in the M3/M4 forums many users report the M performance HAS has a stiffer ride than standard. They say comfort now feels like sport, sport like sport plus and so on with the M Perf compared to stock.

[zero21]

Originally Posted by M Division

Interesting considering in the M3/M4 forums many users report the M performance HAS has a stiffer ride than standard. They say comfort now feels like sport, sport like sport plus and so on with the M Perf compared to stock.

Yeah. Remember though the front springs are already stiffer on M2, and the chassis has extra bracing. So the M2 may already be that much stiffer feeling.

[spademonkey]

I have the M Sports Suspension on mine and it is very comfortable, and definitely very good handling for a stock, out of the box package of a car. Was worth the few extra weeks waiting for it at port to get that installed.

[Slick1984]

Originally Posted by spademonkey

I have the M Sports Suspension on mine and it is very comfortable, and definitely very good handling for a stock, out of the box package of a car. Was worth the few extra weeks waiting for it at port to get that installed.

What a ride. Beautiful. Is that a crown vic cruiser next to it? Didn’t realize they were still in service!

[cmgbk75]

Originally Posted by spademonkey

I have the M Sports Suspension on mine and it is very comfortable, and definitely very good handling for a stock, out of the box package of a car. Was worth the few extra weeks waiting for it at port to get that installed.

Great to hear. Did you have any other port options installed besides the CF side bit & MP HAS that added time? How many weeks did it add?
Thanks.

Do you have any straight on profile pics you could share?

[spademonkey]

Here are the pics of ride height and the one of the front you asked for.

So that is a Spec P71 car, my roommate does that series with it.

And I got rear lip carbon, exhaust tips carbon, the M Sports HAS Suspension, front lip and canards carbon, front intakes, carbon, and sideskirt add-on in carbon. Added about 2.5-3 weeks to port time cause we added it on only a few days before it got to port.

[cmgbk75]

Originally Posted by spademonkey

Here are the pics of ride height and the one of the front you asked for.

So that is a Spec P71 car, my roommate does that series with it.

And I got rear lip carbon, exhaust tips carbon, the M Sports HAS Suspension, front lip and canards carbon, front intakes, carbon, and sideskirt add-on in carbon. Added about 2.5-3 weeks to port time cause we added it on only a few days before it got to port.

Thanks! Is that the 10mm F&R BMW recommends?

[spademonkey]

I believe so, I didn't ask for anything out of the norm so it should be. I sell BMW's so I just trusted the port and my Service techs to do a good job PDI'ing the car.

I'm about to install the iND paint matched front reflectors, gloss black rear reflectors, and the black M2 badge as well to clean up the looks of the car.

Waiting to find some good forged wheels and stickier tires for track days and autocrosses. Gotta sell off my mustang gt parts first though.

[cmgbk75]

Originally Posted by spademonkey

I believe so, I didn't ask for anything out of the norm so it should be. I sell BMW's so I just trusted the port and my Service techs to do a good job PDI'ing the car.

I'm about to install the iND paint matched front reflectors, gloss black rear reflectors, and the black M2 badge as well to clean up the looks of the car.

Waiting to find some good forged wheels and stickier tires for track days and autocrosses. Gotta sell of my mustang gt parts first though.

Do you by chance know how long the MP HAS takes them to install? I’m curious how much it’ll add to my port visit. It’s been on my build for a month and the car is currently at the port of exit.

[spademonkey]

So we asked them about 3-4 days after it got there, and they said the only thing holding up the car at port in Oxnard was the suspension, so I'd say it adds 2-2.5 weeks at the most. Well worth the wait honestly.

[Ravenseal]

Originally Posted by spademonkey

So we asked them about 3-4 days after it got there, and they said the only thing holding up the car at port in Oxnard was the suspension, so I'd say it adds 2-2.5 weeks at the most. Well worth the wait honestly.

That’s longer than I’d want my car sitting at port. Might leave it as a future upgrade tbh. We know for sure the labor is not 3 weeks worth. So it’s either parts are slow or there is a labor backlog. I’d wager the dealership can do it in two days.

[cmgbk75]

Originally Posted by Ravenseal

That’s longer than I’d want my car sitting at port. Might leave it as a future upgrade tbh. We know for sure the labor is not 3 weeks worth. So it’s either parts are slow or there is a labor backlog. I’d wager the dealership can do it in two days.

I figure a week for the port HAS since the parts should be there already. A week extra when I’ve waited this long will be worth the extra 2 year warranty piece of mind along with it being on Moroney and the dealer labor pricing has been pushing it over $3k all in.

[Ravenseal]

Originally Posted by cmgbk75

I figure a week for the port HAS since the parts should be there already. A week extra when I’ve waited this long will be worth the extra 2 year warranty piece of mind along with it being on Moroney and the dealer labor pricing has been pushing it over $3k all in.

You’ll still have warranty if the dealership installs it. It’s 2yr for any BMW original parts installed by an authorized service center. But yes, dealerships are more aggressive on pricing.

[cmgbk75]

Originally Posted by Ravenseal

You’ll still have warranty if the dealership installs it. It’s 2yr for any BMW original parts installed by an authorized service center. But yes, dealerships are more aggressive on pricing.

Yes, but 4 years at the port. That’s what I meant by 2 years extra.

[spademonkey]

Also here is an image I took of the suspension today when the wheel was off for wheel measurements.

[Sherlock997]

Originally Posted by VIERsr

Does anyone know the spring rate of OEM springs and M Performance springs?

I'm curious about this as well but considering they are progressive springs and not linear, stiffness would more likely be translated as an increase in percentage over stock unless someone happens to put them on a spring dyno and documents rates at specific points of compression. From what I have researched it seems they are like riding around in Sport + at all times but some have experienced a slight bounce which does concern me. Wondering if the bounce goes away or is more prominent between comfort, sport, and sport+.

[VIERsr]

Originally Posted by Sherlock997

I'm curious about this as well but considering they are progressive springs and not linear, stiffness would more likely be translated as an increase in percentage over stock unless someone happens to put them on a spring dyno and documents rates at specific points of compression. From what I have researched it seems they are like riding around in Sport + at all times but some have experienced a slight bounce which does concern me. Wondering if the bounce goes away or is more prominent between comfort, sport, and sport+.

The fronts are linear and the rears are progressive.
Beyond everything, if the spring rate is higher, the ride will inevitably be stiffer.
But since the front springs are stiffer and the rear springs are softer versus the M4 - and the MP springs are the same for both - it would be nice to understand how much they affect the ride of the M2.