AST Suspension

[fsmtnbiker]

Do you have your adjuster on the top or the bottom of the spring?

If you put it on the top, it will self-center on the nub on the body as you lower the car. There is about a .5" gap on mine when it is jacked up, but the springs are still kept in place by the nub. I run a lower 8 or 10mm spring pad, no upper.

[kenster]

I can pull out the springs and adjusters on mine at full droop easily. It hasn't been a problem for me. When I drop the car from the stands, everything lines up properly and the adjuster goes over the nub in the body. I guess this is just something you have to trust. I remember reading a little while ago that Vorshlag was looking into Hypercoil springs which would act as helper springs and take up the slack in the rear. Can't remember all the specifics though.

I'm still playing around with ride height and spring rates on mine.

[Fair]

Yes, the springs do realign with the body "nub" when using AST adjustable rear ride height perches. We've got several new springs being made for us by Hyperco as well as some other new Vorshlag bits for the E30/36/46 rear suspension.... we're testing prototypes this week and we'll have some news soon.

Lots and lots of cool new products coming from both Vorshlag and AST.

[Danny318]

Oh I thought you were talking about the fronts. yeah my rears are the same, but you wouldnt want to have the rear up that high anyways.

[epj3]

Yes, the springs do realign with the body "nub" when using AST adjustable rear ride height perches. We've got several new springs being made for us by Hyperco as well as some other new Vorshlag bits for the E30/36/46 rear suspension.... we're testing prototypes this week and we'll have some news soon.

Lots and lots of cool new products coming from both Vorshlag and AST.

Just to let you know, these things are sexy as hell. I have to get the wheels back on and torque 'em up... and I'm ready for my test drive.

It looks like the one front shock (oem) pretty much shit itself

[kenster]

Yes, the springs do realign with the body "nub" when using AST adjustable rear ride height perches. We've got several new springs being made for us by Hyperco as well as some other new Vorshlag bits for the E30/36/46 rear suspension.... we're testing prototypes this week and we'll have some news soon.

Lots and lots of cool new products coming from both Vorshlag and AST.

you guys are always up to something ...

[clopez95m3]

Yes, the springs do realign with the body "nub" when using AST adjustable rear ride height perches.

Terry can you comment on initial damper settings for AST 4200s?

Either with 550/675 or 450/600 spring rates. That would be great.

I'm not worried about my nubs.

Carlos.

[John in Houston]

Terry can you comment on initial damper settings for AST 4200s?

Carlos... what application?

For the street I run 1 click of rebound (upper adjuster) and full soft on compression with 600/700 springs.

For auto-x (depending on surface / temperature / laziness) I usually run 5 clicks of rebound F&R. 6 clicks of compression front, 7 rear. Of course, this also takes into account my swaybar settings as well.

Hope this helps. I think you'll find that you will need to play with the compression more to suit your surface / car setup, but that the rebound number above is probably a pretty good place to start.

[fsmtnbiker]

For the street I run 1 click of rebound (lower adjuster) and full soft on compression with 600/700 springs.

I'm pretty sure the Rebound is on top, and Compression adjuster is on the bottom. But you've gotten that backwards before.

[John in Houston]

I'm pretty sure the Rebound is on top, and Compression adjuster is on the bottom. But you've gotten that backwards before.

Like every other fkn day, right? I'll edit.

I'm still high on brake-fluid absorbtion, paint fumes and burning M3 insulation

[clopez95m3]

Carlos... what application?

For the street I run 1 click of rebound (upper adjuster) and full soft on compression with 600/700 springs.

For auto-x (depending on surface / temperature / laziness) I usually run 5 clicks of rebound F&R. 6 clicks of compression front, 7 rear. Of course, this also takes into account my swaybar settings as well.

Hope this helps. I think you'll find that you will need to play with the compression more to suit your surface / car setup, but that the rebound number above is probably a pretty good place to start.

John, thanks that works for me. Right now my car is pretty rough on the street but I did change over to spherical bearing shock mounts and spherical bearing rear control arms. Just wanted to make sure I set the ASTs to something reasonable to start from.

Thanks again,
Carlos.

[fsmtnbiker]

Like every other fkn day, right? I'll edit.

I'm still high on brake-fluid absorbtion, paint fumes and burning M3 insulation

Got the roll bar in, then??

Carlos - I use similar settings to John on the street. I run a bit more rebound to keep the body motion under control (2-3 clicks).

For my car (625F/500R) I typically run between 4 and 8 clicks of compression depending on surface (and usually the same F & R, haven't had enough time to play with changing the balance) and 5F/7-8R rebound.

One more data point.

[John in Houston]

Got the roll bar in, then??

Yup... 3.5 hours of hell

[IBZCPM3]

I have to add my $.02 about the 4100 kit. The installation was nice and easy. Components included in the kits are absolute top notch. I did have a problem with my right rear shock once I got the kit on and had a chance to corner weight and set on a maiden voyage. There was a horrid knocking coming from that corner which turned out to be a loss of shock pressure. They apparently had some early models with seal issues...a binary thing...either the shock is bad or will last the standard duration. I had a bad one.

Brian at Vorshlag, money! Vorshlag, money! AST, nice! I send the shock back and a replacement is coming in the mail at the same time. Lifetime warranty. Was annoying debugging the issues and taking the rear half of the car apart a couple times looking for something I did wrong...but all in all, for the best. Maybe I can get a free T-shirt for my pain and suffering...

[Danny318]

so what yall running for settings/spring rates on your 4100's ?

[M52 POWER!]

550f/600r

[chebimmer]

How many folks are running the 600# or similar all the way around? And if so, your impressions are appreciated.
I am getting close to ordering and want to hear about anomalies

[Don Nguyen]

I ordered 600/700 on a 4100 kit. Once I get it installed, I'll let you guys know how it feels.

[STirish]

How many folks are running the 600# or similar all the way around? And if so, your impressions are appreciated.
I am getting close to ordering and want to hear about anomalies

We're running close to 600/600 with decent auto-x results. Hopefully we'll have access to a skid pad here soon to test different setting and spring rates.

Rob

[Jammer 070]

How many folks are running the 600# or similar all the way around? And if so, your impressions are appreciated.
I am getting close to ordering and want to hear about anomalies

I run 550 /600 ..but TC personally talked me into softening it to 400-500 or 450-500 depending on track. I'll try it!

[John in Houston]

I run 600/700 on 4200s... and other than when it is dead-nutz cold outside (takes the fluid a while to warm up) the ride it great on the street. Much better then when I was running another companies Konis with the same spring rates (actually the EXACT same springs).

[Fair]

I may have posted this before but we ran our daily driven/STU classed E36 M3 with 600F/750R and my wife drove it every day to work like that with no complaints. Going from twin tubes to ASTs allowed us to not only bump the spring rates up but still improved the ride markedly. We ran with AST4200s then we tested with and ran 4300 triples before '07 Nationals. She drove it like that to her second strait class win at the SCCA Solo Nationals.



We usually recommend street rates a tick less than what we ran (750 pounds/inch springs get into the "harshness zone"). Your tolerance level and your local roads really dictate a lot, as does driving style (some racers like softer spring rates that allow a lot more chassis movement/communication; personally we feel that stiffer rates that allow less bodyroll and camber loss can be faster). I talked to a guy that lives and drives in NYC yesterday and recommended lower rates due to the legendary street surfaces he travels on (aka: the surface of the moon).

[motomoron]

I picked up a set of new strut to spindle hardware at the stealership on the way home from work yesterday, so of course I was up til' 1:30 installing everything. The quality of all the components is superb, and everything fit except one of the big washers for the rear shocks, which was remedied in 5 minutes on the lathe. There are 2 issues I'm iffy on.

• Ride height. The front adjusters are at the very top of their range, and the car is as low as I'd ever potentially want to go. I have zero adjustment up left, and 2" of adjustment down remaining. Why not ship a 170 or 180mm spring so the adjuster is anywhere near the middle of it's range? the rear springs are close. They could actually be shorter. I'm calling today to see if I can exchange for longer front springs. Length was never discussed. I assumed logically that the length would accomodate sdjustment through a track to street range. Mine is low street to lowrider.
• The rear spring seats, or lack thereof. I'm an R&D engineer and product designer, and I'd never dream of releasing this as a product for sale. While it's entirely likely that the spring will "center" itself on the rubber upper or lower BMW spring pad (depending on whether the AST jacker is installed top or bottom) there should be a positive means of centering the spring. I ended up making a pair of machined HDPE lower spring centering seats. See pics below. I need to turn the lower seat part thinner, but they're close. They will have a center bolt to fasten them over the boss in the lower control arms. NOTE: THIS IS NOT AN INDICTMENT OF VORSHLAG OR AST. IT'S NOT GOOD ENGINEERING PRACTICE TO LOAD A COMPRESSION SPRING WITHOUT PROPER CENTERING, IRRESPECTIVE OF WHETHER IT'S ON A CAR OR A CLOTHES DRYER.
• Edit: Vorshlag is evidently working on a similar but much more professional and evolved solution.
• One more thing. Documentation; there is none. A simple single sheet of basic setup info and dimensions would be a minimum. I suppose it's assumed that this product is being installed by an experienced mechanic or at minimum a dedicated enthusiast, but I'm a engineer-designer-fabricator with a full machine and fab shop at home, and I had to stop and think frequently to be sure I was working in the correct sequence.

Otherwise, the installation was completely straightforward. This weekend's SCCA autocross will reveal more, but in over 20 years of buying aftermarket suspension, this is the nicest stuff I've seen.

[clopez95m3]

.[*]One more thing. Documentation; there is none. A simple single sheet of basic setup info and dimensions would be a minimum.

Agreed. I ran into a little bit of trouble with the sph. bearing RSMs in that I wasn't sure how to assemble them onto the rear shocks. Finally figured out you don't use any of the washers provided with the shocks. I'm still not 100% certain I tightened the top nut/spacer properly. The only thing I could hold onto was the small flats on the top of the shaft to hold it in place while tightening the nut with a big ole wrench. If anyone has suggestions as to what they did I'd be grateful. I know I wasn't comfortable with the idea of putting an impact on it (from previous Koni paranoia).

Carlos.

[fsmtnbiker]

• Ride height. The front adjusters are at the very top of their range, and the car is as low as I'd ever potentially want to go. I have zero adjustment up left, and 2" of adjustment down remaining. Why not ship a 170 or 180mm spring so the adjuster is anywhere near the middle of it's range? the rear springs are close. They could actually be shorter. I'm calling today to see if I can exchange for longer front springs. Length was never discussed. I assumed logically that the length would accomodate sdjustment through a track to street range. Mine is low street to lowrider.

I believe they do this to afford the most inside-tire clearance available. I also run at the absolute end of the adjustment, but it allows me to suck the front tires in a little further (or run larger rubber) which is what I was after.

• The rear spring seats, or lack thereof. I'm an R&D engineer and product designer, and I'd never dream of releasing this as a product for sale. While it's entirely likely that the spring will "center" itself on the rubber upper or lower BMW spring pad (depending on whether the AST jacker is installed top or bottom) to be utterly precise and technical, it a pretty ghetto solution, 'yo. I ended up making a pair of machined HDPE lower spring centering seats. See pics below. I need to turn the lower seat part thinner, but they're close. They will have a center bolt to fasten them over the boss in the lower control arms.
• One more thing. Documentation; there is none. A simple single sheet of basic setup info and dimensions would be a minimum. I suppose it's assumed that this product is being installed by an experienced mechanic or at minimum a dedicated enthusiast, but I'm a engineer-designer-fabricator with a full machine and fab shop at home, and I had to stop and think frequently to be sure I was working in the correct sequence.

I agree on both counts - But Brian and Terry will vehemently disagree on you needing a lower rear spring perch.

Want to make a couple more?