[Chrisred]

Been drooling over the AST 4100 (400/800 spring rate) with Vorsclag cambers and M3 strut bar setup for my xi. But this is gonna cost like $3000 plus....

H&R coils another alternative. Like their linear spring rate over KW's progressive.

AST worth that extra $$??

Gonna track car occasionally.

[Doyle]

Dude, TC Kline FTW. They are cheaper than the AST's, but provide all the same benefits. Also, I'm not sure that the H&R coils are linear. When I spoke to H&R directly, they said they were progressive (with pretty wonky spring rates).

Also, if you want to save money, the M3 strut bar is overkill. Sway bars, and bushings will bring a much better ROI.

TC Kline coils: $1850
Vorshlag plates: $450
Rear Bar: $190 (used for 100-150)
Custom front bar: whatever delrin and some welding costs (200-300?)

Even at the high end all that comes in under $3k. Add in the rear subframe bushings and you are right at $3k.

[Chrisred]

TC don't fit on x-drive. Plus to upgrade with swift springs it ends up costing more than AST.

[Doyle]

Really? Then how did they get on my car?

Also, there is only a minor upcharge for swapping out the springs. Even with the upcharge, it will cost less than the ASTs without springs.

http://www.e90post.com/forums/showthread.php?t=583631

http://www.tcklineracing.com/webdocs...Details690.cfm

[Chrisred]

Nice. I'm prob doing this. I guess a little more $ will be worth it on either AST or TC Kline.

[Doyle]

I went with HyperCoil and couldn't be happier.

If you are looking at doing sway bars as well, def give RRT a call. Since the front bar will be a custom job, they'll know what to do. I've always been impressed with their work!

[Chrisred]

Originally Posted by Doyle

I went with HyperCoil and couldn't be happier.

If you are looking at doing sway bars as well, def give RRT a call. Since the front bar will be a custom job, they'll know what to do. I've always been impressed with their work!

Cool thanks. But read that only rear sway and bushings required only as xi understeers??!!

[Doyle]

It all depends...

However, I have 450/700 springs with the H&R rear bar, and have found that I could use a little more roll resistance up front. After digging, it looks like e90's tend to like around 75% front roll resistance.

It is minor, but it just feels like it would really balance out the chassis.

Def try out the c/o and rear bar for yourself and then go from there.

[modernbeat]

Just plugged all those parts into the Vorshlag website and got this:

AST 4100 Monotube Coilover Struts & Shocks (BMW E90/E92xi)
- Camber Plates Vorshlag Front Plates and Perches
- Front Springs 7" x 550 lbs/in
- Rear Springs Swift 9" x 140 N/mm

$2,478.00

http://www.vorshlag.com/product_info...roducts_id=489

That's $1850 for the AST 4100s, $100 for the Hypercoil front springs, $150 for the Swift rear springs and $379 for the Vorshlag plates.

[Chrisred]

Don't forget the M3 strut bar :-)

[e85sbm]

What is the advantage to installing camber plates and bushings for daily driver street use?

I can understand why you need a sway bar, but don't know the functional benefits of the other parts.

Thanks,

[MJR63]

Go with the AST's....They are fully re-buildable. Most other coilovers you have to throw away if they go bad. You will not be disappointed. I love mine.

[Doyle]

Modernbeat-

Good deal. I was looking at HPA which had the same setup for around $2600. I'd be a bit wary running rear rates that high with single-adjustable shocks, though.

Chrisred-

You really don't need the strut bar. Put that money towards sway bars or M3 rear subframe bushings (which you will NEED if you plan on running springs <600).

e85sbm-

OP said he is looking at doing a few HPDEs. In that case, camber plates will save your front tires. For the street only car: probably overkill. Unless you are looking for serious 'stretch-n-poke'. However, if you are burning up the outer shoulder of your DD tires, then it may be worth looking into.

MJR63-

TC Kline are rebuildable, too. That can also be done domestically, although usually only revalving will be needed.

[Chrisred]

What u guys think bout the UUC front and rear sway bar combo?

[MJR63]

I just ordered the front sway bar. I'll let you know after I install it. If I do the rear I'll think I'll go with the M3 sway bar.

[Chrisred]

Doyle- unfortunately there's a install issue regarding the oem strut and AST coils where the top bolt extends passed the oem strut. With M3 strut bar it solved the problem. And I don't find it logical to run without a strut. But I'll do these first and then down the line I'll do the bushings and rear sway

[Doyle]

The TC Kline have a similar issue, however, the shop I use simply "pinched" the strut brace. Now, there is plenty of room. If you are looking at dropping an extra $300 for the M3 strut brace for the ASTs, I would absolutely steer you towards the TC Klines.

As far as the sway bars, the UUC bars are set up for the stock natural frequency bias. So, by running proper coil over rates, your front will be way too stiff. If you choose the front bar, I would go with a stiffer rear (than what the UUC combo has). Or, you can choose a rear bar and then get your front bar customized with adjustable blades.

[Chrisred]

Originally Posted by Doyle

The TC Kline have a similar issue, however, the shop I use simply "pinched" the strut brace. Now, there is plenty of room. If you are looking at dropping an extra $300 for the M3 strut brace for the ASTs, I would absolutely steer you towards the TC Klines.

As far as the sway bars, the UUC bars are set up for the stock natural frequency bias. So, by running proper coil over rates, your front will be way too stiff. If you choose the front bar, I would go with a stiffer rear (than what the UUC combo has). Or, you can choose a rear bar and then get your front bar customized with adjustable blades.

So is the front sway necessary (ie: would it make a big handling improvement) or just the rear sways and upgraded bushings enough??

[Doyle]

Sway bars are a huge part of proper suspension setup (and in turn, handling). As such, both bars need to be chosen wisely. Proper bars depend on the spring rates you choose. Since driving style differ, I'd advise going with adjustable bars front and rear. That means welding on some blades to the front bar, and either doing the same for the rear H&R/M3, or getting the UUC bar.

Bottom line: if you are doing the rear bar, you should at least look at modifying the front bar.

[UltraRacer13]

OP- I have the setup you have mentioned...AST 4100/Vorshlag/M3 tower brace. Love it. Can't compare to a cheaper version..it is all I know. But I think it is well worth the $$$. As mentioned above, the AST's are rebuildable, so that is worth a lot. The setup is silent, and handles great. I track about 3-5 times / yr. I would like to do the sway bars next.

[Chrisred]

Thanks for the replies guys. I decided to go for the AST/vorschlag/M3 strut combo. Now question is the spring rate.

A- 336F 672R
Or
B- 392F 784R
????

[UltraRacer13]

B