AutoX Gurus: Turner J-Stock or H&R Race/Bilstein Sport?

[z31maniac]

I say that just because it's a proven setup, you can buy the entire kit, put it in and be done. Like you said, it's supposed to be a fun HPDE car, not gunning for FTD at the local Auto-X. And like you said, you can just focus on driving vs. wondering if you have the car setup right (ride height, corner weight, damping adjustment, etc).

www.farnorthracing.com, this guy is big fan of Bilstein stuff, great web site you need to go check it out as well.

I still like coilovers though. And this is the setup I think I'll try out next year, http://www.ground-control-store.com/...hp/II=766/CA=8.

Buy as you can see the Adv Design Double adjustables push the price up to just over $2300, but that is close the J-Stock kit I believe. I also like that you can send your strut housings to GC and they will shorten, weld on M3 tabs, powdercoat them and install and preadjust everything for you. Then you can literally just bolt the assemblies back into the car (on the front obviously).

[87e30]

I think it's interesting that you are comparing roughly 1000lb springs with roughly 500lb springs. One progressive one linear. Seems totally different... althought I've never had either setup or auto-x'd.

GC's koni's works well for me though. :/

[Fair!]

I'm going to be going with 17x8 wheels of some kind and 235 or 245/40/17s, but not R comps just yet. I will be going with an AD08, NT05, or Z1-esque tire instead.

Those can still make some good grip levels, you'd be amazed. Our E30 on 205mm Bridgestone RE01Rs (180 treadwear) always pulled 1.30g lateral on a road course (AST suspension).

I have also decided against going with the 5 lug conversion, as the small benefit doesn't outweigh the added cost of wheels, suspension, brakes, and spares.

Smart. The swap to E30 M3 spindles is getting EXPENSIVE. I've seen used E30 M3 spindles/strut housings selling for as little as $300 to as much as $1000. We're trying to get our hands on any sets we can find...

So....back to my original question: For primarily track and DD use, should I go for the J-stock (or H&R Race) setup for now, and plan to upgrade to ASTs later, or save longer and get the ASTs all in one go?

Well, how important is going fast to you? :)

We recently tested an AST customers old J-stock kit springs and they were very soft. See the listing on our spring rate chart. Not only were they soft, the springs had very little travel before coil bind.

My thinking is: with just the J-stock suspension, I won't be trying to compensate for driver stupidity by fiddling with compression, rebound, or ride height. I would get far better as a driver that way. It would cost more, but I think it the Jstock parts still command a good price even used, so the net cost to me isn't terrible.

Well our 4100 kit is fairly straightforward. Rebound only adjustment is pretty easy to understand, the ride height is usually only set once, and the camber can be changed trackside in seconds (to go from street to track settings).


AST 4100 kit for BMW E30 (shown with optional components)

Our camber plates can also get plenty of negative camber travel (our E30 had over -4° camber up front with a lowered ride height). These also have a unique sealed double row radial bearing that prevents the normal sticking/popping/clicking that other plates end up with after time. We also use a bigger/stronger spherical bearing than other BMW camber plates. Long story short - our camber plates never wear out, never make noises, and never fail. Our lifetime warranty is pretty easy to offer. ;)

[Hellabad]

Reply to original post, with realistic information.

Ok, here are some facts to help you:

The Turner J stock kit is pretty much what it advertised as: Designed specifically for J stock in BMWCCA.

The springs are progressive. That means they are wound so that the coils are soft and then convert to very stiff. This is intentional, and part of what works within the framework of J stock. This is why most people are not recommending it for you. They are not soft.

5 lug conversion. Do not be in a big hurry to do this. If you ever get serious, (you used the phrase "don't club race the car...yet") the 5 lug conversion will be a disadvantage if you ever find yourself in a position to fit into rules. Save this mod for much, much much later. It will be quite a while before your car is capable of needing an extra lugnut because four just isn't enough, or because you are burning up your rotors and you need an extra 17ish mm of brake rotor.

Bilsteins: You are correct that Bilsteins dont like to be lowered, this is the bumpstop, and is further proof that obsessing over "spring rates" has virtually nothing to do with real life.

Coilovers: R3Vlimited sponsor Ground Control has coilover kits that are the best in the world. That is why they are so blatantly copied by others, right down to the GC designed o-ring and tapered rear upper perches that you see posted elsewhere.
A GC coilover kit costs LESS than most unadjustable race spring kits where you are not given a choice of spring rate.

Camber: You cannot get -4 degrees on an e30 without moving the strut top FAR under the sheetmetal (which cannot be done by most if not all camber plates) or by BENDING the struts which is illegal for most race classes. (This has been proven by the way)

Camber plates: I recommend buying camber plates from a company that is on the leading edge of design, not the trailing edge.
R3Vlimited sponsor Ground Control first designed the e30 camber caster plate in 1992 or so. This is the camber plate that has been knocked off, along with all of the disadvantages we didnt't know about from back then.

Take a look at the newest GC camber plates, from the last few years. GC is moving forward and changing and revising the designs as the e30's usage is evolving.

That first camber plate we designed was specifically for Improved Touring, and is perfect for that use still. But in the years since, we have designed and built Rally camber plates, Street camber plates, and now have a BRAND NEW, revolutionary e30 camber plate design.

Where are these original designs? Most of them are on the GC website, but as far as the new designs go...

The new designed parts are on race cars, street cars but not on our website, we want to make these guys work extra hard at knocking off GC designs. If you would like a pic, send me a pm.

This is NOT the newest design, but it is still more advanced than any other camber/CASTER plate available. (except for the new GC ones ;))

[z31maniac]

Opinions on the Koni SA's vs DA's vs Advance Design available in the hardcore track kit?

[Hellabad]

Opinions on the Koni SA's vs DA's vs Advance Design available in the hardcore track kit?

First off, I am not going to talk about AST shocks. I have seen the "discussions" on beanerforums, and I would never wish R3v to turn into that pile of disinformation.
(note that the defintion of "disinformation" is quite different than the definition of "misinformation").

Starting with Bilstein, because O.P. has these:
There are two disadvantages to Bilstein. Honestly, the quality of the parts is very high, but the application falls short. They are not adjustable for damping. thats it that kills the deal for me, because you will always wonder if the shocks are right or not. Second disadvantage is the bumpstop/travel, which can be worked around if you know what you are doing.

Koni SA:
I only want to talk about adjustable from the top.
Front: standard length 325. Dont do it, you need shorter ones.
GC custom valved: good for street, good enough for most amateur racing, has warranty.
Koni race valved. very stiff, probably not too stiff, has race warranty (defect only, not wearing out)

Rear:
there are no original top-adjust rears, so there are 3 choices.
Mustang rear. Cheap, too soft for racing, softer than a regular Sachs e30 stock shock.
GC rear. Stiff enough for medium racing and serious auto-x, has warranty, designed as dual purpose. Not too expensive.
Koni race rear. Race warranty, works really good, pretty cheap.($199)

Advance Design struts and shocks (double adjust):
Custom made in USA. Race only. Not ever intended for the street, so this may not be for you. This is because they are designed as a race strut from the start, and can never be soft enough even for transit. Think of it like a a huge cam. Awesome on the track, but it wont idle, it has no power at low end, but is faster than any cam with streetability.


Koni Double adjust:

Front : Rebound on top, bump on bottom, race warranty, $299, quite suitable to race on. Good for auto-x to tweak transitions.

Rear. two choices:
Generic. Works better than single adjust generic, has warranty, reasonable price.
Custom e30: takes a while to get, can be made into a coilover, race warranty





Jay

1343

[akorcovelos]

Bumping this oldie but goodie.

OP, what did you end up doing?

I just ordered some j stock springs alone, not the kit or even the shocks. My current setup is H&R race &325e bsports. I was planning on just running the bsports with the j stocks for now to see how they handle. Bilstein will revalve them for $65 ea. plus shipping but not sure what turn around would be, and I'm not sure its worth it versus the stock bsports valving?

[Bimmerman325i]

That is quite a bump from the dead! I ended up realizing it would cost more money to put coilovers and a bigger engine and bigger brakes and bigger wheels and wider tires in my e30 than it would cost to buy a prepped e36 m3, so I sold the e30 and bought an m3 with tck da suspension. I also, later, bought ast4100s for my dd subaru.

I've been happy with that setup for a while. Probably will upgrade to the new ast4250 in a year or so, but the suspension isnt what needs attention right now.

[akorcovelos]

Haha, guess that's one solution, need suspension, buy new car. :)

Im stoked to see how these j stocks work out, still on the fence about revalving though.

Funny how in my post above my autocorrect added 325e to the spring shock description...

[Bimmerman325i]

there was more to the decision, but yea. I have a feeling the reg billy sport will be quite underdamped with the strong jstock springs. Revalving would probably be a good idea, and $65/ea is asteal.

[Earendil]

Bumping this oldie but goodie.

OP, what did you end up doing?

I just ordered some j stock springs alone, not the kit or even the shocks. My current setup is H&R race &325e bsports. I was planning on just running the bsports with the j stocks for now to see how they handle. Bilstein will revalve them for $65 ea. plus shipping but not sure what turn around would be, and I'm not sure its worth it versus the stock bsports valving?

I'll take a page form you book and bump this from the dead, though not quite as dead as what you pulled off :)

How did the transition from H&R Race to J-Stock go with the same shocks?

I've seen a few people state that because of the incorrect valving on the sports shocks, that H&R Race would actually perform better than J-Stock. I realize Billy sports are far from ideal, but I would have thought the J-Stock spring rate would still be an improvement, matched or not.

Thoughts?