$2000 on suspension for track/autox/DD hybrid

[BiscottiGelato]

I know it's a small budget... and probably $500 of those are going into Ground Control Camber Plates. What should the rest go into? I can do a 0 to ~0.5" of drop. Don't really like the very slammed look.

Auto X and Track combines to about 5-6 times a year? Car is a DD all year round otherwise. Stock wheels on PSS. Everything else stock for now. Brake pad/cooling/rotor upgrade next.

Thanks!

[Focusedintntions]

Get some Koni yellows in addition the brake upgrades in addition to some of the performance springs. I think you'd be really happy with that setup for what you do.

[GaryS]

I don't think you should spend money on rotors unless your stock rotors are worn.

If you're going to leave the pads on for dual use, I guess Ferodo is best. Even better, keep the stock pads for street and swap in Hawk DTC30 for autocross and track.

You need race brake fluid too. For 5-6 times a year, Motul RBF600 in spring and something like Motul 5.1 after end of season should be fine.

At the same time, put in 70/30 water/coolant plus Water Wetter. I don't know where GVA is, but if it gets cold, go back to regular mix for winter.

I'm not clear on how important SS lines are. Most people say it's important. I personally didn't notice the difference.

PS springs plus Koni Sports is a good plan. If you can do the work yourself, I'd say M3 rear subframe bushings too. If you can't do the work yourself, I guess it's too expensive.

You should probably also get a E92 M3 front rollbar. Most people think it helps. And for $65 this thing is a no-brainer.

That's all you really need. If there's money left, spend it on track days.

...adding: I forgot to mention titanium shims for the front brakes.

[BiscottiGelato]

Focusing on the suspension for now, because I want to make sure my new tires are going to wear evenly. I will think about brakes when I killed both the stock pads and stock rotors. Probably shims, lines, pads and backplate... Fluids will be changed before every track day. Unless there's some neat adapters for bigger rotors starting to become available by the time my rotors are trashed, I'll stick with stock rotors also.

I'll definately look into Performance springs and Koni Yellows. Thanks!

[BiscottiGelato]

And, sorry for the noobish question. What is the biggest difference between the Koni Yellow shocks compared to the one included in the BMW Performance Suspension kit? Koni shocks runs for ~$600 new and the springs are about $100 a pop. So that's 1k. The Performance Suspension Kit, which includes a whole slew of other stuff, is 1.2k. Isn't the kit better value? Or is the rest of the kit not really up to snuf? Thanks!

[GaryS]

Sorry, I thought you meant brakes and suspension for $2000.

Anyway, I still recommend the E92 M3 front swaybar and this thing.

If you have enough money left, get M3 rear subframe bushings. They make an awesome difference.

About the PS shocks, Koni Sports are a little more track oriented, but PS shocks are good too.

Does the PS kit have a front swaybar? I think it does, but the people who've tried both seem to prefer the M3 swaybar. ...edit: I remember, the M3 swaybar kit from HPA shop comes with M3 bushings - big advantage.

The best thing about the PS kit is it doesn't let you forget about bump stops. If you do get the Koni shocks separately, you'll need to buy the bump stops separately. BMW part numbers,

31331096099, fronts, each (so order 2)
33536788905, rears, each (order 2)

[cooler2442]

I would just call Harold at HPA and tell him your budget. He should tell you the best bang for the buck in your price range since they did every single suspension mod to their shop 135i before they got the 1M and sold it.

[uberschnell]

I'll take a pass. My experience is tuning both a 335 and 135 for the track.

(This is assuming you have some DIY skills)

Suspension
- Front control arm bushing -$60 - HP Autowerks
- Koni external adjustable sport struts - $868 - HP
- HR Sport springs - $231 - HP
- M3 front sway bar - $265 - HP
- Dinan Camber plates -$200 (cheaper then race plates and won't ruin ride quality the way race plates do) - Dinan
- Powerflex rear-subframe bushing inserts - $160 (Cheaper them M3, able to DIY and 90% as good - I've done both) - Powerflex website

Brakes
- Ferrodo front pads - $214 - HP
- F30 Backing plates - $55 - United BMW
- RBF 600 - $20 - HP
- DIY titanium shims (you can buy a sheet of titanium on ebay for $20)

Now I think this would give you a very balanced upgrade handling wise while still keeping ride quality acceptable for day to day driving.

[BiscottiGelato]

Originally Posted by MteK

I'll take a pass. My experience is tuning both a 335 and 135 for the track.

(This is assuming you have some DIY skills)

Suspension
- Front control arm bushing -$60 - HP Autowerks
- Koni external adjustable sport struts - $868 - HP
- HR Sport springs - $231 - HP
- M3 front sway bar - $265 - HP
- Dinan Camber plates -$200 (cheaper then race plates and won't ruin ride quality the way race plates do) - Dinan
- Powerflex rear-subframe bushing inserts - $160 (Cheaper them M3, able to DIY and 90% as good - I've done both) - Powerflex website

Brakes
- Ferrodo front pads - $214 - HP
- F30 Backing plates - $55 - United BMW
- RBF 600 - $20 - HP
- DIY titanium shims (you can buy a sheet of titanium on ebay for $20)

Now I think this would give you a very balanced upgrade handling wise while still keeping ride quality acceptable for day to day driving.

Do I need external adjustable struts? Or is the regular Koni Yellows okay? H&R Springs drops the car a lot doesn't it? If I don't need external adj struts, i can put the $$ into BMWPS Springs instead or something.

How does the Dinan camber plates stack up to the Ground Control in terms of Streetability and angle adjustments? Seems to be half as much as the Ground Control plates.

[uberschnell]

Originally Posted by BiscottiGelato

Do I need external adjustable struts? Or is the regular Koni Yellows okay? H&R Springs drops the car a lot doesn't it? If I don't need external adj struts, i can put the $$ into BMWPS Springs instead or something.

You would be fine without. It just adds some adjustability for your driving style. Either way it's a step up from stock

yeah, HR drops 1 inch at a min I think.

trust me on the camber plates though

[GaryS]

I don't know. Dinan camber plates doesn't get you much camber. You'd at least need M3 wishbones too to get a little more camber. That would be the setup I have now. It's enough camber for street tires on track, but not really enough for r-comps.

[BiscottiGelato]

Originally Posted by GaryS

I don't know. Dinan camber plates doesn't get you much camber. You'd at least need M3 wishbones too to get a little more camber. That would be the setup I have now. It's enough camber for street tires on track, but not really enough for r-comps.

Not going to go R-Comp. Not planning to win any trophies. And R comp lasts liek 2/3 track days per set? Gonna add another $150~$200 per track day. Not gonna go there. Tracking for me is just for fun and for driving skills improvement.

With that gotten out of the way, is Dinan without the M3 wishbones enough adjustability to ensure reasonable wear on my tires when on the track and when on the street?

[GaryS]

For street only, Dinan camber plates without M3 wishbones would make almost no difference in wear. If you add in 10 track days per year, Dinan camber plates with M3 wishbones would make no difference in wear. Track will eat your tires the same either way. So I really recommend M3 wishbones if you get the Dinan camber plates. It's just not enough camber without them.

[Eyeman]

Don't forget that you'll need an alignment after suspension work, and according to most a corner balance if you do coilovers.

The control arm bushings seem like a great budget idea but the M3 control arms themselves also flex less. If you are gonna do suspension work you may as well figure out which way you want to handle that issue first.

If I were you I'd go for the Dinan plates, M3 control arms, a stiffer sway bar, and ST coilovers set to minimize drop. With install and alignment that shouldn't top $2k by much.

[BiscottiGelato]

Originally Posted by GaryS

For street only, Dinan camber plates without M3 wishbones would make almost no difference in wear. If you add in 10 track days per year, Dinan camber plates with M3 wishbones would make no difference in wear. Track will eat your tires the same either way. So I really recommend M3 wishbones if you get the Dinan camber plates. It's just not enough camber without them.

Yeah, I meant to say even wear/grip across the tire.

[BiscottiGelato]

How about this? See someone trying to sell it used for ~$1k. This is mostly what we listed, aside from the springs being Eibach instead.
http://www.ground-control-store.com/.../II=809/CA=102

[GaryS]

Originally Posted by BiscottiGelato

How about this? See someone trying to sell it used for ~$1k. This is mostly what we listed, aside from the springs being Eibach instead.
http://www.ground-control-store.com/.../II=809/CA=102

I don't know anything about that system, but in theory, it sounds great. The short shocks, custom bump stops, rear shock mounts and ride height adjust should all in theory help comfort without sacrificing performance.

I'm not clear from reading the description whether the shocks are externally adjustable without having to remove them. If the spring rates are high, that's probably important.

Also, someone else will have to answer, will urethane bump stops get noisy over time? I think I've heard about other urethane parts getting noisy with time, but I have no idea if that applies to bump stops.

Sorry, lots of words, but my post isn't that helpful. I only remember one thread about someone getting a Ground Control system, and they spent the whole thread arguing about spring rates.

[uberschnell]

I ran GC camber plates on my car and sold them. Performance wise they are great, but there is no isolation between the struts and your car so it will transmit everything into the cabin. I'm running the M3 front tension/wishbone with the dinan camber plates and getting at least -2.5 and none of the noise I had before.

Also, call GC or AST and ask how many miles they suggest between rebuilds. I believe Harold told me around 30k for the AST's. Mine are in for rebuild now at about 140 a pop and take about a month to turn around. Keep that in mind if you are buying used stuff.

Re: my post above, skip the brake stuff and control arm bushing and get the m3 tensioner/whishbone combo and dinan plates. Improved feel + handling in one shot

[BiscottiGelato]

So I read a bit more since I last posted. It sounds like for this car, the firmer the suspension, the more the weakness of the bushings gets exposed.

My aim is just to have a fun handling car for both DD and track, not so much to build a very fast track car, not necassarily to become the fastest car in my group. Under this pretense, what would be the most effective mods? Would PS Springs and Koni Yellows be too harsh for this? Perhaps I should just keep the stock struts, change over to 2010+ stock linear springs, add camber plates and leave the suspension alone after that?

[GaryS]

Originally Posted by BiscottiGelato

So I read a bit more since I last posted. It sounds like for this car, the firmer the suspension, the more the weakness of the bushings gets exposed.

My aim is just to have a fun handling car for both DD and track, not so much to build a very fast track car, not necassarily to become the fastest car in my group. Under this pretense, what would be the most effective mods? Would PS Springs and Koni Yellows be too harsh for this? Perhaps I should just keep the stock struts, change over to 2010+ stock linear springs, add camber plates and leave the suspension alone after that?

You are right that the stiffer PS springs will expose the weakness of the stock bushings, specifically the rear subframe bushings, which will bounce over bumps. I learned my lesson and always recommend M3 rear subframe bushings with stiffer springs.

But the stock dampers are too soft even for the stock springs. You should upgrade them whether you get new springs or not.

The minimum upgrade I would recommend for every 135i is Koni Sports or FSDs, E92 M3 front swaybar, the $65 HD front bushings, and for track, camber plates. I didn't mention the linear rear springs because I don't have any experience with them, so I don't have an opinion about them.

[BiscottiGelato]

Originally Posted by GaryS

You are right that the stiffer PS springs will expose the weakness of the stock bushings, specifically the rear subframe bushings, which will bounce over bumps. I learned my lesson and always recommend M3 rear subframe bushings with stiffer springs.

But the stock dampers are too soft even for the stock springs. You should upgrade them whether you get new springs or not.

The minimum upgrade I would recommend for every 135i is Koni Sports or FSDs, E92 M3 front swaybar, the $65 HD front bushings, and for track, camber plates. I didn't mention the linear rear springs because I don't have any experience with them, so I don't have an opinion about them.

Thanks for the advice. So I guess this would be the list of items I am contemplating.

- Koni Yellow Shocks x4 (How often do people play with the rear external adjustables? Want to know if it's worth it)
- 09 Stock Springs vs 2010+ Linear Springs vs PS Springs... or other Spring recommendation with minimal drop but won't expose the subframe bushing weakenss too badly?
- Ground Control Hybrid Camber Plates vs Voshlag Camber Plates? I know the Dinan doesn't give enough camber without M3 wishbone, which would probably put me into a hole of getting the M3 tension rods and M3 control arms also..? Probably also stiffen stuff up too much in the front to expose some bushing weakness up front.
- E92 M3 front sway
- HD front bushing

[BiscottiGelato]

Hmmm... reading even more... isn't the front sway gonna increase understeer? I am already on 225/255 staggered. Maybe the front sway isn't such a good idea? In general, isn't stiffening anything in the front going to increase understeer? That goes for the HD front bushing also.