c-channel spring spacers - tell me

So in an attempt to get a slightly higher rate and slightly lower stand height on the e30 rallycross car, I picked up some H&R sport springs.

As is always the case with aftermarket springs, the advertised "drop" isn't really matching up with the actual "drop"

Since I was only looking for a minimal drop (I have room to spare on this car due to much weight reduction), but with the spring/rate I got (or slightly higher), I was looking into using some of the rubber 1" spring spacers.

These aren't the "blocks" that go between the coils that dragsters use, these are a molded piece that sit above or below the spring inside the perches.

similar to this but less "customized." I picked up the ones Jeg's sells for 1" lift (which will really end up being about 1/2" in reality)

Two things: 1. Yes, I realize that this will increase the effective rate of the spring since it will compress them further. I actually want that, so that's not an issue. They are progressive springs, so basically I'll be getting rid of the initial softer rate more than anything. 2. No, I am not going to get GCs or coilovers at the moment. These are the springs I have, and they'll have to do for the season, or use the stock ones that put me up in the stratosphere, higher than I need to be for rallycross.

So basically my question is not about performance, or rate, or stance or any of that. My real question here is "ARE THEY SAFE?"

Because in the end, that's what matters. I just want to get input on whether this can be dangerous (e.g. the spring somehow slips off the perch?). For some reason I just can't think tonight.....wasted years of engineering school I guess.

btw, this is for front only. The rear on the e30 has spring pads that can be stacked or changed as needed.

So, thoughts are welcome.

Looks fine to me. Would it have any more of a chance of slipping off that than it would the stock seat on the strut?

well, IDK. The stock seat has a metal lip on the outside of the spring (at least on the bottom seat), and a 1" spacer would lift the spring itself above this lip.

I was actually thinking that I could always just bust out the welder and make the lip taller with some metal scraps, but IDK if that is needed. I mean, if the spring is under preload at all times (it won't be loose even at max droop), I would assume it's self-locating and won't go anywhere.

These have a "groove" for the spring to sit in, but they're made of rubber (not steel) so wasn't sure....

But again, for some reason I can't visualize it in my head this evening.....too much other stuff on the mind. I know 4x4 guys use spacers like this all the time (I actually have similar metal ones for our 4Runner sitting in the garage, but it's a different suspension setup).....but of course they're not driving quite as aggressively as I am, lol.

btw, you going to the TN Regional in June?

more accurately, they look like this:

I mucked about with the ones that went between the coils and always ran them right down as far as I could get them. I didn't have any problems with them. I did drill a couple of holes through them and zip tied them to the springs when I put them in though. Can you ever unseat the springs as you have them? If not I wouldn't worry about it, they'll be fine. If you extend the strut all the way and the spring rattles then I'd make sure that the rubbers are tied to the springs. As far as increasing rate, not really if you put them on the bottom of the spring. You're not really pre-loading the suspension in the strictest sense I don't think, you're just changing the part of the stroke that the strut is in that you're using. The only time you'll experience a higher rate is when you go from completely unloaded to the beginning of being loaded. Don't catch air and it won't matter.
Edit: Those are exactly what I have. Drill some holes through them and zip time them to the spring if you're nervous.

thanks.....where do you have them? between the coils, or actually above or below the entire spring?

got any pics?

and yeah, I have the front suspension apart at the moment, so getting them in isn't a concern.

I think the only pictures I have of them are in this thread: Spring Rubbers This is before I drilled holes in them. When I ran them I pushed them all the way down as far as. I could get them, on the coil right against the seat. You might also spend some time thinking about bump stops. There is quite a lot of behavior that can be changed with them. I think if you do it right you can use the bump stop to progressively up your rate in the last two inches of travel and take the edge off the hits. Something to think about when you run out of other stuff.

irish44j wrote: btw, you going to the TN Regional in June?

Strongly considering it.

great, thanks. I think I'll try them on the bottom (the ones I got only are grooved on one side, I think, and flat on the other - so meant to go on top or bottom).

I've yet to even touch the bumpstops with my tall stock springs, all the weight off the car, and Bilstein HDs (at least I don't seem to). With the car lower I suspect I will notice it more and will go from there. We'll see how this works out first :)

EvanB wrote:

irish44j wrote: btw, you going to the TN Regional in June?

Strongly considering it.

I just signed up. There's a '75 BMW 2002 signed up in MR as well...and another e30 from florida coming up. Should be good times. Still trying to figure out whether I want to drive this car 9 hours in the heat of summer or trailer it with the 4Runner though.....

Come on...I drove the Miata 16 hours to nationals in a race seat.

(Although I would have trailered it if I had the capability)

Hint - a bandana/towel soaked with water around your neck works wonders.

yeah, I know. I've done 16 hours both ways to florida in the summer in my old integra with no a/c so I know..

my main concern is some kind of breakage....and we have a 2-day big rallycross the next weekend up here, so I can't be without the car.

Plus the 4Runner is such a pleasant cruiser, lol.....and someplace to sleep if I'm too cheap to get a hotel room :)

Hmmm.. I need some of these for my Jetta that was lowered a bit too far.. I was thinking CV boot straps looped around the spring/rubber/strut seat to keep them in place.

NASCAR racers use spring rubbers as tuning pieces all of the time.

We used them from time to time on the stock car. If you are concerned about them popping out sometimes we would run a few zip ties around them and the spring to make sure they stayed in place.

Here is a brief article about what they do: http://www.stockcarracing.com/techarticles/39758_what_are_spring_rubbers/viewall.html

Got them in, just to follow up. Also put some "retaining" pieces on the spring seat, just for peace of mind. These are pretty hard-durometer rubber (harder than I was expecting) so I don't expect I'll need those, but can't hurt.

I don't see how it's going to to affect the spring rate if you put it at the top of the bottom of the spring. You're not compressing the spring further, it'll compress just as far when you put the car on it.

Putting it between two active coils, that's different.

Keith Tanner wrote: I don't see how it's going to to affect the spring rate if you put it at the top of the bottom of the spring. You're not compressing the spring further, it'll compress just as far when you put the car on it. Putting it between two active coils, that's different.

yeah, I wasn't thinking when I said that. Seems to happen a lot when working on this car, for some reason

these already have a considerably higher rate than the stock 318i springs....the main goal was to do it while losing minimal height, really.

I've heard setting the ride height on an E21 lower at the rear and higher at the front does good things to the geometry.

I wonder if that's true and since the E30's suspension is very similar if the same would hold true for them as well?

Well, it definitely increased rear camber. By my measurements I'm at almost 2 degrees negative in the rear, as opposed to 0 degrees before (stock springs + weight reduction). So I'm hoping by dropping the rear 1.5" and the front only 0.5" I can settle the rear end down somewhat and get back some traction.

irish44j wrote: 1. Yes, I realize that this will increase the effective rate of the spring since it will compress them further. I actually want that, so that's not an issue. They are progressive springs, so basically I'll be getting rid of the initial softer rate more than anything.

why would they do that? I don't think it is going to compress them any further, as the only thing holding the car up is the springs... and all you did was (essentially) move the spring mounts UP.. not compress the springs further. (also since they are softer than steel.. they actually soften your ride a TINY bit).

all they would do is raise the car, and soften the ride a tiny bit. if they were the ones you put in the middle of the coil, then they would lift, and stiffen.