3DM TTX Öhlins Suspension for High Horsepower Applications
- Thread starter fmorelli
- Start date
Not going for flat ride in this scenario. Flat ride is more suited for "grand touring" street oriented kits, we are applying that principle to the F10 5 Series we are working on. If you did flat ride in this Z4 setup it would be an over-steering nightmare, not what you want with a car that is going to be producing 600+ whp. Current spring setup is 70/120.
As for the right setting on the first go... I knew what force curve I wanted to obtain and set the valving so the rebound and compression were at click 10 each to get that force curve. TTX has about 25 clicks total so we have plenty of room to tweak. If needed when development/testing is done I will revalve and bring the adjustment back to the middle.
the sleeve is the biggest issue in my case since machine work costs more than everything else...
anyways i will wait and see there are solutions to this.... thanks
I think there is an F30-based solution coming, for the e8x/e9x, which gets the better hub carrier geometry. @ShockandAwe is running the F80 hub carrier, I think, which is similar (a bit more reinforcement and I don't remember if geometry is identical). Anyway yeah if you are willing to wait a bit, I suspect Barry will have a solution in SKU format, so to speak.the sleeve is the biggest issue in my case since machine work costs more than everything else...
anyways i will wait and see there are solutions to this.... thanks
Filippo
Well define suspension development haha. If you mean adapting motorsport dampers to the E89 Z4, I can't think of anyone other than you. And afaik noone has done any actual damper logging with proper equipment on the Z4.
I had custom 1 way dampers made to spec for my own car. We got some stuff right and some other stuff less right. I might order a new revision at some point.
Today my custom rear sway bar should finish production. I was finding myself always running the stiffest position rear (HR), so I wanted to balance that out. Not sure if that falls under active suspension development. Of course we are also looking into the cost of having custom front uprights made to spec, but that is most likely not happening. Will see. I also calculated the wheel spring rates based on the springs I use and the work done by wranda back in the zpost days. That was why I wondered how you decided to go with linear springs as well as what wheel rates you were aiming for.
Everyone I know in China either goes for KW v3 or just lowering springs and call it a day. And I dont understand how KW came up with this setup for the Z4, it doesn't look ideal:
Hahaha ... well to be fair, I'm not doing the suspension development. That's Barry - he's the expert with the 20 years of domain chops I lack. On suspension, I'm just helping on the wrenching side. I don't have the background and make no pretenses I'm not the expert on the subject.
I just asked if you were aware of someone else, given what you said. I didn't know from your commentary (you mentioned some technical tradeoffs) if you had seen some suspension engineering guys doing stuff with any of these cars. There are various cars (ex GT3 etc) and I just didn't know if you had stumbled across some folks.
Filippo
A quick FYI on the rear mount on my setup...
I'm running double eyelets in my rear TTX, lower M3 camber link mount and upper Turner Motorsport solid RSM.
Using swift 10" rear coilovers springs with some generic TCK height adjusters I had laying around. Also have some custom spring pads in the camber link.
Formerly had Dinan RSMs.
If anything there's less NVH, no need to drill the frame, just make sure you have a 34mm socket on hand to install the Turner mount through the trunk.
-Alex
I'm running double eyelets in my rear TTX, lower M3 camber link mount and upper Turner Motorsport solid RSM.
Using swift 10" rear coilovers springs with some generic TCK height adjusters I had laying around. Also have some custom spring pads in the camber link.
Formerly had Dinan RSMs.
If anything there's less NVH, no need to drill the frame, just make sure you have a 34mm socket on hand to install the Turner mount through the trunk.
-Alex
the sleeve is the biggest issue in my case since machine work costs more than everything else...
anyways i will wait and see there are solutions to this.... thanks
I'm running the F8xM upright with E9xM3 R&T front. @Hydra Performance makes a caliper bracket which allows this to work with the E46CSL 2pc front rotor. No sleeves required for the spindle clamp.
-Alex
i can see this become an interesting upgrade for guys that wants to take corners fast... i dont mind waiting althought i dont think its high on his priority list
how much does the F8xM knuckle push the front wheel out? i have a custom AP Radical BBK already so i will need to plan for this as well...
Well I can't speak for @barry@3DM, but given the discussions we've been having over the past several weeks, I'm not so sure I'd say it is not high on the priority list.i can see this become an interesting upgrade for guys that wants to take corners fast... i dont mind waiting althought i dont think its high on his priority list
With the F3x knuckle we really did not notice any significant spacing change in the wheel well, if that is the question. I'm running a 19x9 ET35 front wheel with 245/35-19. I have a 3mm spacer up front though we might be able to run without it. With the R&T setup/stock E90 hub carriers on the prior revision, we needed a bit more space on the tire to spring clearance. It's not clear that we need it in this case. But given what I am seeing, I believe this will be a no-contact fitment as was the prior configuration, and possibly without the spacer.
Filippo
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actually i am interested for both f3x and f8xM knuckles...how much camber are you running?
for reference i am on a e92, with a 18x9 ET31 wheel with 255/35 or 30/18 tire..and superpro adjustable camber/caster control arms so my control arm length can vary by a little
at -1.5 degrees of camber i have around 3-5mm of clearance
at -2.8 degrees i have around 10-12mm ish
I calculated the wheel frequencies as below
This is based on the assumptions (from this source) that the front rate is 96% and the rear rate is 55% for E89 Z4. I do not know if these rates are correct.
The detailed calculations are found in attached excel sheet I got from @AzNdevil and updated with Z4 data.
Ok finally wrapped up alignment on the 2nd revision of the suspension. (alignment scales under the trash bags)
Toe: (Front: 1mm in) (Rear: 1mm in)
Camber: (Front: -2°) (Rear R -2.5°)
I was hoping to get some seat time with the car, but I have an issue I'm still working with the rear brakes. Soon ....
Toe: (Front: 1mm in) (Rear: 1mm in)
Camber: (Front: -2°) (Rear R -2.5°)
I was hoping to get some seat time with the car, but I have an issue I'm still working with the rear brakes. Soon ....
why are you running only -2 in the front but hefty -2.5 in the rear?
On my e92 i am running probably -3 in the front and -1.5 in the rear and last week on the Nordschleife ist was pretty perfect. Car was going with no understeer into the corners and mid corner to end corner it was very well balanced with oversteer only when forcing with throttle.
On my e92 i am running probably -3 in the front and -1.5 in the rear and last week on the Nordschleife ist was pretty perfect. Car was going with no understeer into the corners and mid corner to end corner it was very well balanced with oversteer only when forcing with throttle.
If true likely the TTX damping. That said I'm on -2.5F and -1.8R with my TTX hybrid setup albeit 1er chassis. Very mild push for safety which is easily overcome with the ultra short wheelbase.
Alignment rig - scales under the trash bag, digital readout, etc. This is what Barry uses at the track, and what he used when running GrandAm.
As for the numbers - E89 Z4 is, first of all, not an E92. Barry has driven the car and this is where he landed on how it is set up with the suspension at hand.
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