Open Light Subaru build
Posted by modernbeat
Jason McDaniel Senior Moderator Location: Dallas, TX Join Date: 12/14/2007 Age: Possibly Wise Posts: 401 Rally Car: 1963 SAAB Historic, 1995 Impreza Open Light totaled at WRC Mexico, 2005 STi Pikes Peak winner |
Albert Kun Super Moderator Location: SF Ca. Join Date: 01/07/2008 Age: Possibly Wise Posts: 1,732 Rally Car: volvo 242 |
Matt Follett Elite Moderator Location: La Belle Province, Montreal Join Date: 03/13/2006 Age: Midlife Crisis Posts: 645 Rally Car: Don't Laugh, the Justy is Fun! |
Alex Rademacher Infallible Moderator Location: Reno,nv Join Date: 09/10/2007 Age: Midlife Crisis Posts: 686 Rally Car: 93 GC with an 01 RS swap! |
wow the coil-over got ripped from the knuckle. or the knuckle got ripped from everything (A-arm and coil-over) owie
"It sheared ACROSS the strut body" Wow ... bad jump landing ? just bad luck? any video of the super special jump? |
John Vanlandingham Godlike Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
Yeah have to see that. Specially since I just welded your rears with the new Cr-Mo ears. John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
Banned Godlike Moderator Location: the end of the universe Join Date: 02/12/2006 Age: Possibly Wise Posts: 1,432 Rally Car: 1980 Opel Ascona B |
So I'm a little late to the party because I never really looked at this thread but I can give a little insight to all this rear geometry/strut housing flange bending thing. The bottom mount for the rear strut is offset to the centerline of the hub. This puts a twisting motion into the strut mounting bracket. I've seen and repaired dozens and dozens and dozens of bent DMS brackets, all on my own time because Jamie Drummond's shit don't stink and he refused to put gussets on the brackets which would pretty much solve the problem. Even without ever taking a hard hit the brackets will eventually twist and crack, it's just how the geometry is back there. A horizontal gusset on the top and the bottom of the bracket goes a long way to help prevent the problem. |
Alex Rademacher Infallible Moderator Location: Reno,nv Join Date: 09/10/2007 Age: Midlife Crisis Posts: 686 Rally Car: 93 GC with an 01 RS swap! |
Jason McDaniel Senior Moderator Location: Dallas, TX Join Date: 12/14/2007 Age: Possibly Wise Posts: 401 Rally Car: 1963 SAAB Historic, 1995 Impreza Open Light totaled at WRC Mexico, 2005 STi Pikes Peak winner |
John Vanlandingham Godlike Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
Yep it appears there is a geometry problem. I have been thinking hard--or as hard as my old noggin can---and thinking about arcs. We want the strut to move in the 'up'n'down part of the arc, and not "over the top" of the arc which is where the forward direction has to be coming from. So the latest stuff I have made the bottom tube about 1" or so longer. The idea is that with the longer OAL, you can still let it settle to have decent droop but its still longer even when compressing. Maybe the rears of the cars need to be up a bit higher, too. Here is where good visualisation skills would help a lot. Of course it be REAL wonderful if there was a better, NORMAL upright that would fall in place with the strut in line with the spindle, or maybe just longer N/S links to make a slower arc. Or even better, everybody could move up in the world: 
Betcha they ain't bending no stinkin rear strut! 
Just the whole car!! Yikes! 
It happens! John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
Alex Rademacher Infallible Moderator Location: Reno,nv Join Date: 09/10/2007 Age: Midlife Crisis Posts: 686 Rally Car: 93 GC with an 01 RS swap! |
for cars going by an open rule set. they could modify their spindles to be more like the fronts (with the attachment point directly over the axle, instead of (in front?)
Won't help the "must bolt onto factory mounting points" crowd ... What if the ears were offset so that the strut was more up and down?  (possible a horrible idea since I've never seen it done or maybe genius! )
just playing with a pencil and my finger to simulate the rear trailing arm Arc . yes as it compresses there's a point where the bottom of the strut is moving forward. the further back you can move the strut it appears the forward motion is less .... Or maybe its just something we have to live with.. how do the rear struts attach to a GD impreza? exact same way or are their rears directly over the axle... anyone have a pic of a GD rear knuckle? and how about a pic of a WRC rear knuckle ? (maybe even from the 93-99 era?) |
Aaron Luptak Elite Moderator Location: SLC Join Date: 02/15/2008 Age: Midlife Crisis Posts: 776 Rally Car: Civic... |
These two pics from subaruwrcspares.com say "S5-S11" and "S5-S12b", and one google search for S5 mentioned 1998... 
  KF7RWG 
http://www.utahrallygroup.com |
Banned Godlike Moderator Location: the end of the universe Join Date: 02/12/2006 Age: Possibly Wise Posts: 1,432 Rally Car: 1980 Opel Ascona B |
GD rear knuckles are the same as GC8. The reason the Subaru has the strut mounting point offset is to allow room for the CV joint and axle. It's something you have to live with. Gusset the brackets but don't be surprised if you see more bent inserts as a result. Usually not a problem if you're not bottoming out a lot and clobbering stuff. And don't use spherical bearing top mounts on the rear. You need more give than that. 2WD Imprezas did have the strut mounting point in the centerline of the hub but obviously they're useless for an AWD car. |
John Vanlandingham Godlike Moderator Location: Ford Asylum, Sleezattle, WA Join Date: 12/20/2005 Age: Fossilized Posts: 14,152 Rally Car: Saab 96 V4 |
And for comparison:  John Vanlandingham Sleezattle, WA, USA Vive le Prole-le-ralliat www.rallyrace.net/jvab CALL +1 206 431-9696 Remember! Pacific Standard Time is 3 hours behind Eastern Standard Time. |
Alex Rademacher Infallible Moderator Location: Reno,nv Join Date: 09/10/2007 Age: Midlife Crisis Posts: 686 Rally Car: 93 GC with an 01 RS swap! |
Banned Godlike Moderator Location: the end of the universe Join Date: 02/12/2006 Age: Possibly Wise Posts: 1,432 Rally Car: 1980 Opel Ascona B |
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