[williaty]

First of all, let me state that for purposes of easy discussion, I'm somewhat overstating the differences, advantages, and problems with the different damping setups. The actual differences are quite small and would be very hard to talk about if I didn't blow them out of proportion a bit.

Second of all, the car is heavily modified and I'm a perfectionist when it comes to this stuff. I freely admit that I'm being really damed picky about this.

Here's the mod list in case anyone thinks it's relevant:

2005 Impreza 2.5RS Wagon in Regal Blue Pearl
Basic Suspension: Full Sedan Front End Conversion, USDM STi Springs, Tokico D-Specs, PolTec Heavy-Duty Endlinks, Whiteline 22mm Adj RSB, Whiteline QR Rear STB, GT-Spec ALK, Whiteline Max-C Motorsport camber plates, Whiteline KCA313 Roll Center Adjustment Kit, Turn In Concepts Fender Braces
Bushings: Full STi Group N Lateral Link, Trailing Link, and Rear Strut Mount Set, Kartboy Tranny Crossmember, TiC Comfort Rear Diff, Whiteline Steering Rack, Interestingly Hacked Outrigger Bushings
Brakes: OEM blank rotors, Carbotech Bobcat Pads, TechnaFit Stainless Steel Brake Lines, ATE Superblue Racing Brake Fluid
Competition: Primitive Racing 3/16ths Front Skidplate and Rear Diff Protector, Alfa Club Rally Odometer/Chronometer, Schroth Rallye 4 Quick-Fit Harness for the Navi
Powertrain: Stainless Steel Borla-Replica UEL Header Coated with Extreme Sterling by Jet-Hot, Stromung SS 2.25" Midpipe, DIY Catch Can, Group A Performance Lightweight Crank Pulley, Hybrid Silentake, Group A Performance Throttle Body Spacer, RomRaided
Electronics: Hawker Odyssey PC-680MJT Battery, Hella Rallye 1000 FF Driving Lights and Micro DE Fog Lights, Rear Deck Light Addition, Map Light Addition, Hella Supertones, Innovate Motorsports LC-1 WBO2 w/ LED Gauge
Rolly Bits: Summer-16" OEM wheels in Falken FK452s | Winter-16" OEM Wheels in Hankook Icebear W300s

For the record, the bar is set on it's 22mm equivalent setting.

Now, for most of the last 6 months or so, I'd managed to be happy with my damping settings. There were definitely a few road conditions that upset things a little but overall it was good enough. However, in the last month, I've done the sedan front end conversion, the Whiteline Roll Center Adjusters, and the TiC Fender Braces. After getting all this done, I came to the conclusion that something wasn't quite right with the damping.

It's very hard to say exactly what didn't feel right. The car soaked up bumps well (in the sense of not getting the chassis upset). It cornered pretty well. It didn't bounce too much. However, there were a couple of things that bothered me. In my area, we have a freeway overpass where you basically get dropped about 3" from the tarmac of the freeway to the concrete of the bridge. It just felt like it took the car one bounce too many to settle after the drop. Certain bumps and dips in the road would also unsettle it. If, for instance, all 4 wheels were moving on their own, some up, some down, the car would kind of roll around like a jello mould as though the tires were getting confused as to where they were supposed to be. The chassis itself wasn't moving so much as the suspension was just working overtime in a very inefficient manner. Finally, the car didn't react very well to overly-quick steering or throttle/brake inputs. It was like it got pissed off if you jerked it around too much (which obviously I try not to do as smoother is faster).

So I turned all 4 dampers stiffer by the minimum amount I could. Again, the results are a mixed bag. Dropping off the ledge sees the car settle instantly. However, there are other sharp transients that now see the car feel like it "bottomed out" even though it isn't using NEARLY enough travel for that to be happening. It's kind of like if you hit the wrong kind of bump, the car just sort of goes "ooof!" as it falls down off the bump. The rolly/wobbly/confused feeling is gone as well. However, those same conditions now see the chassis itself seemingly get upset. The actual body of the car rolls and bounces MUCH more now than it did before. It sort of feels like the tires are more under control, but the chassis itself is paying the price for that. Finally, it's become unable to soak up certain kinds of bumps. The car is, interestingly, MUCH less upset if you get too rough with the steering wheel. Before, you could hit pretty much any kind of bump mid-corner or in a straight line and the car would just kind of roll over it without the chassis going anywhere and without breaking traction. Now, the car feels like it gets "tossed up into the air" over bumps. This makes it much harder to carve a perfectly smooth arc through the corner AND results in a short chirp of tire squeal on the down side of every bump. It's like the bump fires the chassis itself up more and then the tires can't get back down to the road fast enough.

Anyone have any thoughts?

[twiSTies]

A couple things to throw out there...

Does the sedan front end conversion add or lose weight on the wagon?

Have you tried to adjust just the front dampers and not the rears from your initial settings to compensate for the changes in front geometry and weight or overhang differences from the swap?

Why 16 inch tires and wheels? What tire pressures?

Whats your ride height at and alignment settings?

How many miles on the D-Specs?

Honestly, what you're describing reminds me of my old BC Racing coilovers when they were on all-season tires and weren't set stiff enough.

[williaty]

Originally Posted by twiSTies

Does the sedan front end conversion add or lose weight on the wagon?

Dunno. Going to guess it adds a little bit of unsprung weight due to the 10mm extra length to the control arms. But it's likely less than 1lb/side.

Have you tried to adjust just the front dampers and not the rears from your initial settings to compensate for the changes in front geometry and weight or overhang differences from the swap?

I have played with the ends independently with no clear improvement.

Why 16 inch tires and wheels? What tire pressures?

The car goes off tarmac quite a bit. I'd kill low-profile tires and wheels in a heartbeat. A 205/55R16 is the smallest sidewall that will survive me. 40psi hot on all 4.

Whats your ride height at and alignment settings?

Ride Height:
-FR: 15-3/8"
-FL: 15-1/4"
-RR: 14-3/4"
-RL: 14-11/16"

That translates to 1/4" lower than stock on both ends.

-1.5* camber front, -0.7* camber rear, 0 toe all around.

How many miles on the D-Specs?

23,000 and change.