Steering Knuckles for Competitive Driving & Alignment Specs

[Pierre]

Originally Posted by Eco-Mod

Just took a look at the GMPP knuckles and compared them to stock, they are much beefier, and the strut to knuckle mount is moved slightly further away from the wheel. I'll try and put up some pics tonight after work.

Is there any drop by relocating the spindle in relation to the ball joint mount with the new knuckles?

Pierre

[socalsilverRL]

Originally Posted by pierre

I'm not considering the Cobalt arms in this discussion.

Don't you want less than 90 degrees at static ride hight? you should hit 90 deg somewhere in the middle of your wheel travel or towords the latter part. That way you minimize the track displacement through wheel travel and will have the most camber gain when the car rolls to the extent that you can with a mcperson strut. If you start at 90 you can only go down in the angle from there.

Pierre

^the cobalt a arms bolt right in to our suspension, thank djt for that.

As far as 90° suspension angles and such, the strut works best at 90°. So you want to keep the strut at 90° whenever possible. When you go changing geometry to 70° your strut will bind more often and result in a harder spring rate...making it hard to turn.

These knuckles are for serious racing, mainly because GMPP found on their Grand Am vehicles, that the stock knuckles would buckle under hard cornering. Thats why they replaced the knuckles on the Cup car to Grand Am knuckles.

(according to the Solo2 guy i bought the rims from) if you want to keep even tire wear when adding camber, you add more caster and a little tow out. (According to SCCA rules) We can actually drill out our strut mount all the way to the crease on the tower, which allows us to add -2° of camber to our car.

[Pierre]

Originally Posted by socalsilverRL

^the cobalt a arms bolt right in to our suspension, thank djt for that.

As far as 90° suspension angles and such, the strut works best at 90°. So you want to keep the strut at 90° whenever possible. When you go changing geometry to 70° your strut will bind more often and result in a harder spring rate...making it hard to turn.

What I am saying is keep your strut near 90 degrees over it's compression operating range. If you set it for 90 at ride height it will only decrease as the suspension compresses.

In fact as the angle becomes less than 90 degrees the spring in the strut will have a lesser effect because of the angle. Your wheel rate will decrease.

Pierre

[socalsilverRL]

^ok...so i had it backwards...i thought you meant 70° the other way...lol

..yea keep the average angle at or around 90° so a little more than 90° at ride height.

[Eco-Mod]

Yeah I'll admit I didn't slow down to double check my wording/thought process. I fixed my earlier post about the angles. I SHOULD have said that having a GREATER than 90 degree strut to control arm relation will cause negative effects by not allowing a greater increase in negative camber during turning, just didn't go from my head to the fingers right. So < 90 degrees = good >90 degrees = bad.

And for the rear, you can shim it. The BWoody rear bar allows a small amount of change in camber, but it more importantly effects rear toe which should be your first/main concern back there.

The new knuckles really don't change alot, which you will be able to see in the pics I'll have. It's really just a stronger knuckle that uses all the other stock pieces.

[scottherbert]

Does anyone have a copy of the graphic from a 2006 Saturn ION Redline maintenance manual that depicts how to grind-out the strut mounting hole? I had one from a 2005 manual but I can't find it. As was mentioned earlier, you can get an SCCA-legal 2 degrees of negative camber 'if' you happen to have a copy of the page showing the modification when you're tech'd.

I'm going to be running at an SCCA National Tour Event in the near future and need the graphic to show to tech...

Thanks in advance,
Scott

[Eco-Mod]

Um, there isn't one that I know of... I can check, but I'd just use the lobed camber bolts. Do you REALLY think they can see though metal? Plus I doubt you really need to grind them out that much, if at all, I've only had to do it on one Ion out of all the ones

[alredline04]

Someone posted a picture of it a while back. I just cant find it.

[alredline04]

so, Eco, Did you put these on yet? Just curious if there are any suprises. I will be ordering mine in March.

[BigBrother]

+1 requesting if anyone has that page. I HAD IT PHOTOCOPIED AND LAMINATED DAMNIT and now I can't find it. The local Saturn dealers have only online manuals that don't have the same detailed info, i.e., specifying the additional 2 degrees - and yes, it spec'd 2 ADDITIONAL degrees, you can get over 3.5 degrees of negative camber by grinding that mount LEGALLY in Solo 2...

I'm currently running -2.5 passenger side, -2.7 drivers side. In the begining of the thread, people are talking about -1.5 degrees ruining tires, lol... I have pretty even wear - but I corner hard enough to wear the outside 'evenly' with the faster wearing inside, LOL.