[4banger]

Awesome post, Stretch. You didn't happen to ask Mark about shock dyno plots, did you?

[stretch]

Originally Posted by AnorexicSTI

1. I like your weighing methodoligy . We're going to get along. Now, by any chance can you weigh the stock setup so we know how much we're saving over stock?

Weighed them. 17.5lbs each, so a 4.5lbs savings per corner.

Although, these being non-inverted struts, there is probably a small gain in unsprung weight.

[thrlskr]

Originally Posted by stretch

Although, these being non-inverted struts, there is probably a small gain in unsprung weight.

Are there any other drawback to the non-inverted design? Is the more deflection under lateral loads argument valid?

[stretch]

Originally Posted by thrlskr

Are there any other drawback to the non-inverted design? Is the more deflection under lateral loads argument valid?

Sort of. Yes, it makes sense, but I haven't seen any Koni (or other non-inverted) struts fail prematurely due to high lateral loads, have you? The struts have a lifetime warranty if needed anyway.

The advantage to a twin-tube damper like this is the lowest possible amount of friction in the design for good ride quality. So, like everything else in the world, it's a trade-off.

[RainMaker]

Originally Posted by stretch

The best solution to the suspension travel problem is to buy an adjustable length strut, like what Zzyzx sells. Notice how the entire strut body is threaded on those. Rather than fooling with various-height strut tops, you can just shorten a Zzyzx strut and accomplish the same thing. It's a much better solution that is sadly only commonly seen on cheap throw-away Japanese coilovers, done so they can reuse one model strut on several cars.

The Ohlins Flags have the same feature. Incredibly helpful. You put the strut where you need the travel.

It becomes slightly more complicated though when you need more droop travel than the car will compress the stiff main spring under normal load. You then have to get some kind of helper spring, which takes up room when compressed (tire clearance gets hurt) and can cost a bit of money, though the rear is the only place its needed.

[thrlskr]

Originally Posted by stretch

Sort of. Yes, it makes sense, but I haven't seen any Koni (or other non-inverted) struts fail prematurely due to high lateral loads, have you? The struts have a lifetime warranty if needed anyway.

The advantage to a twin-tube damper like this is the lowest possible amount of friction in the design for good ride quality. So, like everything else in the world, it's a trade-off.

I didn't think the deflection represented a potential point of failure as much as an inconsistent alignment when under cornering loads. Am I wrong?

[MTR]

Sorry for the noobish question but I want to make sure I understand this correctly.

To measure the total amount of suspension travel you would measure the shaft of the strut before its compressed by the spring? And then to figure out how much droop (travel for potholes) and bump (travel for speed bumps) you could attach a zip tie around the shaft, slide it to the bottom, lower the car, then jack it back up and measure how much its moved? So length below the zip tie would be droop and above would be bump?

Also couldn't you figure out how much weight was on each corner if you had linear springs, knew the springs stiffness (lbs/in), and the length that it compressed (in) while under load? (taken from the zip tie measurement)

This is just the way I figured would work in my head, is this correct? Or is there an easier or better way of figuring this out. Thanks

[stretch]

Originally Posted by RainMaker

The Ohlins Flags have the same feature. Incredibly helpful. You put the strut where you need the travel.

It becomes slightly more complicated though when you need more droop travel than the car will compress the stiff main spring under normal load. You then have to get some kind of helper spring, which takes up room when compressed (tire clearance gets hurt) and can cost a bit of money, though the rear is the only place its needed.

Why do you want more droop travel if your spring is already completely unloaded? What do you hope to accomplish? Heck, your spring shouldn't ever even fully unload on any car running a sway bar.

[stretch]

I went ahead and began evaluating these coilovers on some local roads known to be brutal on shocks. It was too nice a day not to take advantage. My drive included turns with sharp elevation changes, old, broken roads, speed breakers from hell, and various shaped speed bumps.

These coilovers are very quiet. After deliberately going too fast (15mph) over a speed breaker (short, stubby speed bump), the only noise the front tires made was from that little plastic ring on the strut bouncing. Clearly I would have hit the bump stops on this impact but they felt very soft and progressive.

Grip seems to be way up, but I attribute that to the added camber inherent in the coilovers. Whatever its limit of grip, the car is now much easier to drive at that limit. It doesn't skip over bumps anymore, not even under hard cornering or braking. My spring rates are near identical to what I was running last week, so I know this change is due to new front struts.

By looking through the fender gap, I can plainly see it is an inch above the bump stops at rest. My measurements suggest that the car is likely just barely off the bump stops mid-turn at my ride height. This means I would hit the bump stops if I hit a bump mid-turn, but the bump stops seem soft enough that I haven't found this problematic. I do wish I had another half inch of bump travel, though, and am tempted to buy the Ground Control camber plates to get it.

The only thing that upsets the car at all is very lopsided road imperfections, in other words when one wheel hits a bump and the other hits a hole. The chassis seems to teeter-totter a bit and is primarily due to the stiff sway bars on the car trying to resist roll even when the asphalt is slanting. Comfort here has been still increased a bit, but it just goes to show that not all problems can be fixed with good dampers.

My new Koni setup feels very much like what the original equipment should have felt like. Only the largest road imperfections (think: raised manholes in a construction zone) are able to rattle the coins I have sitting in the cup holder. I won't blow smoke in anyone's face and say that it feels like a luxury car; it simply doesn't. It instead feels like what I expect in a factory sports car- firm, but smooth, and always predictable. Predictability is a great thing to have.

I'd read GC adjusts the coilovers to match your chosen springs before shipment- true or not, I left them at the factory setting. (I sent an e-mail to Mark to confirm, cause I'd love to play with them if I can.) The GC front Koni struts feel just like my WRX cut-and-gut Koni rear struts; they match well. Bumps have a near equal impact front and rear. Prior to installation, I was a little worried about the struts not matching one another. (Thanks guys for making me worry!) I still have the rears set to full soft.

The car feels a little underdamped compared to what I'm used to, but I keep thinking of Dennis Grant saying something to the effect of almost all sports cars are overdamped. Since car control is already very good in this setup and both grip and ride quality are equally superb, I have no real motivation to try stiffer settings.

I still have to get an alignment and then comes the wife test.

The package feels exactly how I hoped it would.

[twiSTies]

Originally Posted by stretch

The only thing that upsets the car at all is very lopsided road imperfections, in other words when one wheel hits a bump and the other hits a hole. The chassis seems to teeter-totter a bit and is primarily due to the stiff sway bars on the car trying to resist roll even when the asphalt is rolling. Comfort here has been still increased a bit, but it just goes to show that not all problems can be fixed with good dampers.

Yup, those are what upset my car as well with the coilovers. The rest of your review sounds very similar to how its going for me right now, although I'm not sure if I have an inch of bump travel under load. I do know that my setup isn't perfectly quiet--there is noise in the rear..i'm going to go and check to make sure everything is tightened down when I put my x-brace in.

I'm glad you're enjoying the Konis, sounds like a great setup that you discovered for everyone else!

[[pK]Lightning]

Okay, so I've been keeping up on this thread, and the suspension frequency thread as well. The roads where I live are subject to constant water/freeze, so potholes are my way of life, that and construction... Long story short, I'd rather do stiff sways and soft springs to get the right frequency. However, I also do HPDE and track days, so I want performance. I'm sure I'm not alone in this boat. This GC setup sounds damn good, but I'm confused because when I first considered throwing springs on the car I called GC and they said ALL their springs would be MUCH stiffer than stock, so I avoided them. Thoughts on this? From what I've read, Soft springs & stiff sways seems to be the best idea for me...or should I focus more on dampening? I plan to do sways, springs, struts, and plates. Opinions? Suggestions?

[4banger]

Originally Posted by stretch

Remember, though, that perfect suspension travel setup only happens at one ride height. According to Mark, that happens at a 14.5" ride height on roughly 380lb/in springs. If you lower your car further, you're still sacrificing bump travel for wasted, useless droop. However, this isn't always a bad thing- with 3.5" in reserve, you could probably safely lose an inch of that (by lowering the car another inch).

Isn't 14.5" the stock ride height, in front? Stretch - was Mark's suggestion 14.5" front or all around. As much as I like how my car looks lowered now, I think I want to raise it back up and I'm curious to see what the Guru's think the perfect ride height is.

BTW, the 380lbf/in equals 1.9 Hz, which sounds about where I would want it.

[stretch]

Originally Posted by [pK]Lightning

Okay, so I've been keeping up on this thread, and the suspension frequency thread as well. The roads where I live are subject to constant water/freeze, so potholes are my way of life, that and construction... Long story short, I'd rather do stiff sways and soft springs to get the right frequency. However, I also do HPDE and track days, so I want performance. I'm sure I'm not alone in this boat. This GC setup sounds damn good, but I'm confused because when I first considered throwing springs on the car I called GC and they said ALL their springs would be MUCH stiffer than stock, so I avoided them. Thoughts on this? From what I've read, Soft springs & stiff sways seems to be the best idea for me...or should I focus more on dampening? I plan to do sways, springs, struts, and plates. Opinions? Suggestions?

Well they're certainly wrong to have said that considering they'd sell you your stock spring rates on request! The important thing with potholes is having lots of suspension travel. For that, you're going to want those GC camber/caster plates, 375-400lb/in front springs, and 300-325lb/in rear springs. Pair them with 24mm front and 22mm or 24mm rear sway bars. I think you'd be very happy with that setup.

[stretch]

Originally Posted by 4banger

Isn't 14.5" the stock ride height, in front? Stretch - was Mark's suggestion 14.5" front or all around. As much as I like how my car looks lowered now, I think I want to raise it back up and I'm curious to see what the Guru's think the perfect ride height is.

Stock is closer to 14-3/4 or 15 inches front, just under 14 inches rear. It seems to vary from car to car slightly.

[4banger]

Thanks Stretch. I think the number I found must have been for an '04, which I didn't realize was lower than our 05's.