Originally Posted by
Pat Olsen
Spent quite a few hours this weekend working on the new suspension. I was actually hoping to get this all done this weekend, but doing this "right" entailed a bit more than I expected. I've been taking some pics with my new digital camera, but I'm on not on the right computer to upload stuff, so the pics will come later.
First, the basics. I'm installing Koni inserts into a set of '97 2.5GT struts. Along with that I’ll be putting on some Ground Control coil-over sleeves with 325# springs up front and 280# springs in the rear – 100# higher than my DMS Golds were at both ends of the car. The setup will be complemented by a set of Noltec caster/camber plates in front, some Sti top mounts in the rear, plus my already-installed Whiteline swaybars front and rear and comfort-bushed ALK.
I had to contact Koni to figure out the right fitment, as their catalog is (not too surprisingly) based on UK/JDM model years and model designations. With some emails bounced back-and-forth with Koni, and an email to Subaru of America, I figured out that what I needed was:
8610-1318 for the front and
8610-1317 for the rear.
The Koni online catalog only shows a rear application for the '96-98 model years, so I had to email SoA to confirm that my '97 front struts were made by Showa, and sure enough they are, which meant that the 8610-1318 shown for earlier years will work for me. The rears are clearly stamped "KYB", but the fronts don't say Showa on them anywhere - they say "SUNBURY", which I guess is a factory location or something like that, I dunno.
Last week I acquired a spare set of '97 2.5GT struts, so I've been able to butcher them without worrying about my car being out of action.
Step one is to drill a small hole (3mm per the instructions, I used a 1/8") in the bottom of the strut housing to drain out the original fluid. I was a bit worried about how much pressure might be in the housings, and what kind of mess I was going to create in doing this. Well, with the fronts I learned my fears were unfounded - drilled the holes, pumped the fluid out (by cycling the strut by hand), good to go.
The rears were another story. With the longer housing and strut rod, I had to compress the strut to get it into the vice I was using. I drilled the first one, and as soon as the housing was breached pfffffftttt this spray of oil comes out! Pressurized oil spray + small hole + spinning drill bit inside of hole = mess. Fortunately I was wearing safety goggles while drilling, but I still got a bit on my face and head. So, for the 2nd rear strut I figured, "Ahhhh, compressing the strut to fit in the vice is a bad idea!" so I rearranged how I put it in the vice so that the strut was fully extended. Yeah, uhhhh, that didn't help, and I got sprayed again. Oh well, live and learn....
Once the fluid was drained/pumped out of the four struts, it was time to cut the tops of the strut housings off so that the stock innards could be removed. The Koni instructions show how far down the strut body you're supposed to cut, and the dimensions are based on the location of nubs on the sides of the Koni inserts up towards the tops. Those nubs are what locate the inserts tightly inside the factory housing, so you have to be sure you don't cut off too much of the housing or the nubs won't be inside the housing and hence the insert would be free to wobble around. Make sense? I measured the nub locations (which are different on the front and rear struts), subtracted the 7mm the Koni instructions specify, and came up with 1.47" for the fronts and 1.72" for the rears (or something like that). I ended up deciding to just cut them both to 1.5", and then if I needed to I could take more off the rears.
I already had one of those chain type pipe cutters, so I figured I'd use that. Well, that gave me mixed results. On the rear struts, the cutting point was in thinner metal, with a wall thickness of 1/16" thick or so - a little thicker than your typical exhaust tubing. The cutter didn't have any problem with that. Once I had made the cuts I could see that just below where I had cut the metal thickened up a bit, which would have made it more difficult to get through. Turns out, on the fronts I had to cut through that thicker metal. The first one I went most of the way through with the chain type pipe cutter, but the little cutting wheels were starting to bottom out and it couldn’t quite finish the job. So, I finished that one off with my Dremel. I decided to skip the pipe cutter for the second one, and instead went with a hacksaw (which is actually what Koni’s instructions show). It actually wasn’t too bad using the hacksaw.
OK, pulled out the stock innards, time to move on to the next step. The instructions say to enlarge the holes in the bottom of the strut housings to 14mm. Again, no metric drill bits to play with, so I went with a ½” (12.7mm) and figured I could enlarge that as necessary. My drill was being a real PITA at this point, kept slipping on the bits no matter how hard I tightened down on the chuck. I’m thinkin’ the spray of strut oil straight up the 1/8” bit into the chuck probably didn’t do much for its ability to grip. Eventually, though, I managed to get all four drilled out. Turns out (from what I can see thus far – haven’t finished the install yet) that 12.7mm is plenty big as long as you are careful about getting the hole right in the center of the bottom of the housing. I had to Dremel two of them a little bit, but the other two were fine as is – I would guess the bolt that holds the inserts in is only 12mm, so the 14mm the instructions specify is probably just to give you a little wiggle room to account for drilling slightly off-center.
At this point I could have installed the inserts into the housings, but I decided to do a couple other things. First, since this is a spare set of strut housings, I can safely cut off the spring perches since I won’t ever be putting stock springs on these. That’s what I spent time doing today. Even using an air grinder and cut-off wheel it took me quite a whle, probably 15-20min for each strut. I guess it makes sense, though – those perches are holding the weight of the car, so they gotta be pretty beefy. I left about a ½” lip – basically, the horizontal part of the perch right up against the housing – for the GC sleeves to rest on.
Once that was done it was painting time. The housings were already in pretty good shape, but the bare metal exposed with the various cuts needed to be covered up, and spray paint is cheap so I figured I’d paint the things completely. Off to Lowe’s I went to pick up some paint and a couple other things (to be discussed later). I debated a variety of colors as I stood in the aisle of spray paint – red to match the GC/Eibach springs, silver to match the car, fluorescent whatever just to be crazy, or – even more crazy – metallic gold or chrome for the ultimate in bling bling suspension. It coulda been sweet, but I decided to stay conventional and just went with some flat black Professional Grade Rustoleum. During commercial breaks while watching Rally France coverage on Speed I sprayed the housings down so they’re all purty again.
So, at this point I’m basically ready to put everything together, but I need to get some 4x4 style shock boots to protect the Konis, and the one 4x4 shop I knew of out here was closed today, and they’re closed Monday too, the bastards. Once I have the boots I’ll be ready to put everything together. Hopefully I’ll be able to finish everything after work this week, get the suspension installed, and get an alignment. I’ve got an auto-x coming up next Sunday, and I’d really like to have everything done by then, but we’ll see.
There will be further updates, including my pictures, as the week progresses.
Pat Olsen
'97 Legacy 2.5GT sedan
When I ordered the GC stuff, Tony at GC told me to make sure I installed the GC sleeves before installing the Koni inserts, because the inserts have a lip at the top that is too big for the GC sleeves to fit over.
Dammit!! So, my first thought was to try to knock the insert back out (the inserts have nubs that are an interference fit in the housing, so they're in there pretty damn tight). I didn't make much progress, since I don't have a vice to hold the housing in, but I did manage to mess up the threads that the bolt goes into on the bottom of the housing.
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