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      03-18-2016, 03:24 PM   #67
DaveJB
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I hate to dredge up an old thread but I figured this would be the best place to ask.

I ordered a set of Fortune Auto 500 coilovers with Swift springs and the radial bearing for my 07 Z4 M Coupe. I'm confused about the rears. Are they coilovers too or is the spring seperate? Also, did it come with a top plate (rears) and if so is it worth upgrading to the Rogue RSM's? Any chance someone can post some pictures of the rears out of the car?

Thanks
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      03-18-2016, 03:27 PM   #68
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Quote:
Originally Posted by DaveJB
I hate to dredge up an old thread but I figured this would be the best place to ask.

I ordered a set of Fortune Auto 500 coilovers with Swift springs and the radial bearing for my 07 Z4 M Coupe. I'm confused about the rears. Are they coilovers too or is the spring seperate? Also, did it come with a top plate (rears) and if so is it worth upgrading to the Rogue RSM's? Any chance someone can post some pictures of the rears out of the car?

Thanks
Can't run true coil overs on the rear without significant modifications to the rear shock towers like a full cage. Simply not strong enough to deal with the forces stock. So it's going to be a shock and a separate spring.

While you're in there yes I would do Rogue RSMs unless the top play lets you bolt and in bolt from the wheel well. That's what the Rogue benefit is (better compliance too from stock). You only want to disassemble and reassemble the hatch area once.
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      03-18-2016, 06:31 PM   #69
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Is there something wrong with the thread subscription notifications?!

Anyway, thanks. Fortune Auto got back to me and confirmed but also told me the kit comes with a replacement rear shock mount. I was hoping someone that has these can describe them and tell me:

1. are these good enough or should I go with the Rogue kit?
2. can these be reversed like the rogue mounts so I don't have to rip the back apart again?
3. How are the damping adjustments made? From the top only? That would suck.

Since Fortune will revalve/rebuild them for only $55 a corner at some point I will need to remove them again so I guess I'd buy the Rogue ones just so I don't have to mess with the hatch area again. I suppose the safe thing to do it order the Rogue mounts and have them on hand JIC.
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      12-07-2018, 12:29 PM   #70
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Hey guys, i am new to these forums. Just purchased a 2006 Z4M coupe, with a low 30k miles. Just needed some opinions on your long term experience with Fortune Auto Coilovers. How is the ride and handling? The car is in storage for the winter, so only going to be driven on nice summer days. And never going to be tracked. Do i need to go the roll cage route like Finnegan mentioned earlier? to have a solid build. Any feedback would be appreciated.
Thanks!
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      12-07-2018, 12:37 PM   #71
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I'm happy with mine EXCEPT they just plain spec'd out the front spring wrong at an inch too short. Found that the shock bottomed out (loud noise) too easily. They always responded quickly to help me resolve it, so that's damn good. They ended up sending me two different 1" longer springs - a slightly used set of Swift and their house spring. I STILL haven't gotten around to replacing the springs though.

Also, they'll rebuild them at any point in their lifetime for just $50 a corner (though you'd have to pay for shipping). That's pretty awesome.
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      12-27-2018, 08:52 AM   #72
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Quote:
Originally Posted by Syed///M View Post
Hey guys, i am new to these forums. Just purchased a 2006 Z4M coupe, with a low 30k miles. Just needed some opinions on your long term experience with Fortune Auto Coilovers. How is the ride and handling? The car is in storage for the winter, so only going to be driven on nice summer days. And never going to be tracked. Do i need to go the roll cage route like Finnegan mentioned earlier? to have a solid build. Any feedback would be appreciated.
Thanks!
Hey! You are local to me!

You only need rear enforcement if you do the "true coilover" setup (spring on shock in the rear). The standard for our cars is the divorced spring mounted separately in the rear.

I have had the FA 500 kit for the last year (swift springs, 9k/11k spring rates, radial bearings, valved for street and autocross use) and they have been really tolerable on the street. Nasty bumps not so much, but nasty bumps were still pretty bad on stock suspension.

I have noticed on occasional big bumps the rear spring does bottom out (I understand this is common on coilover set-ups). I am considering swapping in some TC Kline rear springs to help with this issue, since they use the "beehive" spring design allowing for more spring movement.

IMO, they ride better than the koni adjustable/BMW OEM sport springs on my 3.0i. If you want to see how they handle (both on street and in an autocross environment), come out to a Windy City BMW event once spring arrives! I would be more than happy to take another Z4M owner along for a ride!
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      12-01-2020, 03:04 PM   #73
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DaveJB, what was the spring length before or after? I am also bottoming out more often than I'd like on the front of my FA coilovers.
Also I don't quite see how a longer spring would help.

Last edited by filtercoffee; 12-01-2020 at 03:11 PM..
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      12-01-2020, 04:16 PM   #74
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I suspect Fortune tested their setup with a non M Z4 - I'm pretty sure the S54 engine weighs 100 lbs more. So, they messed up the specs of both front and rear springs. That is, I upgraded to Swift springs and apparently Swift doesn't sell springs in the same lengths as their in house stuff (6" IIRC) so they sent 1" shorter springs both front and rear. IIRC I got 5" Swift springs for the front and rear when these coilovers need 6" springs. Also, the rear Swift springs, while being too short were also just too weak. Over a couple years they compressed/sat shrunk massively. You wouldn't believe the pics I have of them when the rear started bottoming out. So, I've sold the car but here's what I figured out it needed.

Front: 6" Fortune Auto 10k front springs
Rear: I bought my own Eibach 6", 10.7k springs (part 0600.250.0600)

Yes, higher spring rates and the car didn't ride any worse.

Okay, why would it make a difference? The issue I first experienced up front was bottoming out. I figured out that while they claim the usable travel was about 4", the car's static sag was over 50% so as the car sat it had less than 2" of travel before bottoming out. This was all with the too short 5" Swift springs. However, you may be right. The difference might have been when adding the longer springs I also increased the preload which would cause the car and shock to compress a bit less when the car is set onto the ground. Basically, increasing static sag/ride height. So, from my best memory the available suspension travel was just less than 3". So, this with higher spring rates took care of the front end bottoming. Before I did this, it would bottom out on sharp bumps that weren't even 2" tall, and it sounded like a gun going off.

Anyway, I have an 85 email conversation thread with them over the many years getting this worked out. If you need any more help PM me. Attached is a pic of the car as it drove off after selling it, after all the coilover issues were solved.

EDIT: one more note about the rear end bottoming. I found that the spring perches were too long and the sound of the rear bottoming out was the two spring perches slamming together. I shorted them a little. Here's a picture of what they looked like with the overly weak 5" Swift Springs before I put the 6" Eibach springs in. See how close the spring perches are at rest (the black threaded things).

I hate to say it, but at least for the Z4 M I don't recommend these guys. Look, the support and lifetime service are great. So, maybe said another way, do NOT accept the fitment they spec out. Get at least 10k 6" front springs and at least 11k 6" rear springs. In hindsight, since it took so much effort to get it done right I wish I'd bought the Bilstein B12 Shock & Coil Spring Lowering Kit.

And in case anyone is wondering why I'd replace such truly bad ass looking car (IMO), it's because I decided to buy one of these. A 2013 427 Anniversary Edition Corvette. Over 500 hp, convertible, just an incredible car. I LOVE IT.
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Last edited by DaveJB; 12-01-2020 at 04:50 PM..
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      12-01-2020, 08:02 PM   #75
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Quote:
Originally Posted by filtercoffee View Post
DaveJB, what was the spring length before or after? I am also bottoming out more often than I'd like on the front of my FA coilovers.
Also I don't quite see how a longer spring would help.
I spent a lot of time this summer getting my suspension to an acceptable fast road performance state. Check pages 14 and 15 where I posted my findings.

https://nam3forum.com/forums/forum/m...ndation/page14

The car DOES NOT need too stiff springs to ride and handle fine. With the spring selection I got with, my car rides and handles better, and at the rear is still too stiff, but that is the damper, not the springs. I have 250# and 600# springs, fronts are 8in, and rears are 6in, and they don't bottom out.

The front suspension has about 4in of usable travel, the rear has a bit more. Once the car is seating on the ground, our Z4Mīs have 2in of bump travel (assuming OE ride height).

When it comes to suspension you need to look at the whole system, not just springs.

Keep in mind that the moment you lower the car ANY amount, you eat suspension travel, which is the least you want for a road car. Lowering the car via springs and coilover perches is a compromise, there is no way around it. You can achieve some lowering by changing to a shorter camber plate design keeping all else equal.
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      12-01-2020, 10:45 PM   #76
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100% agree with you on looking at the whole system.

Nice work modifying the H&R coils. I see your bump stop is pretty beefy. The FA bump stops are comically short. They're like 1/2in rubber pucks (not a measurement, just from my memory) which I assume was to give more travel. They're probably just there to prevent the shock from breaking on impact. I've bottomed out very hard and the shocks show no sign of damage.

Since I'm in New York, I didn't lower the front much, since I did not want to reduce travel.

My valving is digressive since I have the "MSC" coilovers from FA which go softer at high speed. This is a contributing factor to why I'm bottoming out on large bumps. I'm not considering changing my shocks at this point since the ride is comfortable for the most part, I don't have the harshness issue you had with H&R.

Will see if I can get more info from DaveJB on the rationale for FA's recommendation here with the longer spring.

Update: The FA coilovers ride height adjustment is via the bottom of the shock body, so that wouldn't affect shock travel (w.r.t. "Keep in mind that the moment you lower the car ANY amount")

Last edited by filtercoffee; 12-01-2020 at 10:55 PM..
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      12-02-2020, 01:41 PM   #77
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Quote:
Originally Posted by filtercoffee View Post
100% agree with you on looking at the whole system.

Nice work modifying the H&R coils. I see your bump stop is pretty beefy. The FA bump stops are comically short. They're like 1/2in rubber pucks (not a measurement, just from my memory) which I assume was to give more travel. They're probably just there to prevent the shock from breaking on impact. I've bottomed out very hard and the shocks show no sign of damage.

Since I'm in New York, I didn't lower the front much, since I did not want to reduce travel.

My valving is digressive since I have the "MSC" coilovers from FA which go softer at high speed. This is a contributing factor to why I'm bottoming out on large bumps. I'm not considering changing my shocks at this point since the ride is comfortable for the most part, I don't have the harshness issue you had with H&R.

Will see if I can get more info from DaveJB on the rationale for FA's recommendation here with the longer spring.

Update: The FA coilovers ride height adjustment is via the bottom of the shock body, so that wouldn't affect shock travel (w.r.t. "Keep in mind that the moment you lower the car ANY amount")
it seems then you are under-damped if you are sure you are bottoming out with the rates you have (which are on the stiff side). I have much softer springs and I don't bottom out.

I really would like a damper job with fatcatmotorsports but it is not affordable, to say the least.

The H&R damping is linear but they are very stiff and they have way too much gas force. Based on what I have found is that you are better off with medium springs, the "right" dampers, and sways if you feel spings allow for too much lean during cornering.

I wish you find the balance you want. is not easy and annoyingly there is not a good system out of the box for our cars.
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