Blazer Spindle Oddity

[-dw-]

I do believe gbody bump steer is caused by the outer steering pivot point being too low or inner steering pivot being too high. From what I see in the pics you've gone the wrong direction. Howe had made a circle track center link that lowered the inner tie rod. Taller lower ball joints would raise the outer tie rod. Either would more effectively correct some to the factory bump steer.

 

[bs009]

There's definitely a lot going on to factor into bump steer with the control arm angles that these cars have and the way things change while steering. I'm by no means an engineer and haven't done a ton of research into it, but the kits seem to have pretty noticeable success from what I've heard and are mimicked by a few different companies. lowering the pivot point for the outer tie rod seems to be the way all of the bump steer kits are installed from what I've seen so I'm just following those guides.

Here's UMI's instructions for their kit:

G-Body Steering Upgrade – How to Fix Bump Steer – UMI Performance

How To Fix The Steering and Bump Steer On Your G-Body After Car Craft upgraded the suspension on their G-Body

www.umiperformance.com

TRZ's kit is what I used here because I couldn't find anyone who had UMI's kit in stock when I needed it:

Bump Steer Kit for use with Stock Steering (G-Body)

A must for lowered cars & for cars with increased positive caster Replaces your inner and outer tie rod ends Adjustable tie rod height at the spindle to maintain the correct steering geometry Includes Chrome-Moly Rod Ends, LH / RH tie rod adjusters, 6061 Aluminum Spacers, and new inner tie rods...

www.trzmotorsports.com

http://www.trzmotorsports.com/docs/bumpsteer.pdf

 

[scoti]

G-body bump steer issues are documented as a result of the steering arm pivot point being low. B-body spindle swaps made it even worse.

 

[Streetbu]

G-body bump steer issues are documented as a result of the steering arm pivot point being low. B-body spindle swaps made it even worse.

Incorrect. Hence why all of the bump steer kits move the tie rod downwards. I needs to be parallel to the lower control arm and in the stock location, it's too high.

 

[86LK]

don't forget that his pictures show him up on jackstands. you're not gonna get a real idea of his geometry until he's sitting on the ground

 

[Streetbu]

I would have to disagree. The geometry appears correct at ride height, the problem comes when the suspension ISN'T at ride height. Whether it's at extension or compression, hence, bump steer.

 

[86LK]

I would have to disagree. The geometry appears correct at ride height, the problem comes when the suspension ISN'T at ride height. Whether it's at extension or compression, hence, bump steer.

I'm not saying the damage is not there, what I'm saying is you can't tell how bad it is until it sits on the ground with a proper load on it. The driver side is obviously out of whack, but take a look here at them side by side. It's hard to tell but it looks like the passenger side may have gotten whacked too as it looks like the two lower nuts in front back don't line up in parallel. take a look at the other ones that were posted as a comparison.

 

[bs009]

I think we have two threads of thought going on here now between my issue and what the bump steer correction kits do.

I have no doubt both of my knuckles are FUBAR after seeing the pics Squag posted. Also consider that in the pics I took I can pretty much guarantee the angles the photos were taken from were not symmetrical side to side.
Once the new ones are installed I think I'll see different clearances between the wheel and the tie rod on both sides because what I have now is pretty broken and probably has been the real cause of my horrendous bump steer I've been experiencing for a while. I have not even touched the adjustment capabilities on the bump steer kit either yet so I'm sure it still needs some tweaking.

As far as how the bump steer kits work though I think we'd need a full picture of both sides of the tie rod with both pivot points and the control arms to really see if things are parallel. But then also need to consider typical ride height vs what happens when one side reacts to a bump too to see how that might change the toe; things get complicated fast and this is where I'm just going to try out what the manufacturers of the kits suggest.

 

[bs009]

Got the new ones installed today, thanks to Jamcar for getting them out so soon!
Assuming the rest of the car is road worthy I'm going to try and get an alignment tomorrow!

Driver side was definitely annihilated, passenger side seems like it wasn't actually too far off though. I just replaced both of them though, better safe than sorry.

New knuckle installed on the driver side. This side was pointed straight with the old spindle so that's how bad it was.

I did tune the bump steer kit as best as I could, ended up removing every single one of the spacers it came with so this is about is parallel as the lower control arm and the tie rod can get on my car. I'm using 5658 springs with about 2400lbs on the nose so the car is lowered a little. The springs are new too so it's going to settle a little lower.
Wonder if they've built to kit the suit everything from lowered cars to donks or something to have that much adjustability. This does seem to have placed the tie rod ends higher than the stock position on my car probably because of how low it is.

Passenger side:

Driver side: