Has anyone actually combined tall ball joints with the Guldstrand mod?

[D-Man]

.

70 Camaro.

I see that the AFX spindles are 1.4" taller than stock (which I understand is about as good as it gets for a stock subframe). So I'm wondering if one wants to match that 1.4" can it be done inexpensively with tall ball joints and the Guldstrand mod. Pro forged tall ball joints alone won't do it as they're only 0.5" taller than stock. 2nd Gen Guldstrand mod only lowers the upper mounting points approximately 1.0". However, with both mods it's possible to hit that 1.4".

So what are the challenges (and solutions) with doing both mods?

A arm clearance seems like a simple fix for those of us that weld.

Adjustable shorter upper A-arms to bring the tops back in of course.

Bump steer I've seen mention of tall tie rod ends not being a complete fix. What about lowering the idler arm and steering gear (box)?

Overall it seems very doable. What am I missing?

[Twentyover]

On a 70 camaro, i think the deal is a tall lower joint to prevent bump steer, and the second gen f bodies already have the taller spindle

[D-Man]

Thanks for the reply. From what I've read there isn't a TRE on the market that can correct the bumpsteer for that much spindle height (+ 1.4").


Anyone have an opinion on (correction) raising the idler arm and steering gear?

[c4racer2]

That’s because you may be trying to fix something that isn’t a problem. Are you sure you actually have bump steer ?

[CSG]

Thanks for the reply. From what I've read there isn't a TRE on the market that can correct the bumpsteer for that much spindle height (+ 1.4").


Anyone have an opinion on (correction) raising the idler arm and steering gear?

If going with this combo wouldn't a custom steering arm be easier than relocation of the box?

[D-Man]

That’s because you may be trying to fix something that isn’t a problem. Are you sure you actually have bump steer ?

I'm still in the research stage and haven't done any of these mods yet. I saw in your build thread that you're using stock 2nd gen spindles as well. Not sure what your plan is, but the problem with stock spindles is that even with tall upper ball joints you don't get the camber gain of a modern car. So the wheels/tires don't stay flat on the turf in hard cornering. Hence the Guldstrand mod in addition to the tall upper ball joints. Another option I'm looking at is tall upper and lower ball joints. Which may have some benefits on a lowered car. I'm not sure.


If going with this combo wouldn't a custom steering arm be easier than relocation of the box?

2nd gen camaro OEM spindles have an integral (fixed) steering arm. The only way I know to change the arm height is via custom modification via welding which I won't do.

[79T/Aman]

you're confusing 1st gens and 2nd, also the height of the spindle will not affect the bump steer, all a 2nd gen needs is a 1/2" tall upper ball joint for 95% of applications.

[David Pozzi]

.

70 Camaro.

I see that the AFX spindles are 1.4" taller than stock (which I understand is about as good as it gets for a stock subframe). So I'm wondering if one wants to match that 1.4" can it be done inexpensively with tall ball joints and the Guldstrand mod. Pro forged tall ball joints alone won't do it as they're only 0.5" taller than stock. 2nd Gen Guldstrand mod only lowers the upper mounting points approximately 1.0". However, with both mods it's possible to hit that 1.4".

So what are the challenges (and solutions) with doing both mods?
That might be a good idea, but I think the upper A arm will contact the frame pretty quickly. You might lower it .5" though
A arm clearance seems like a simple fix for those of us that weld.
see above
Adjustable shorter upper A-arms to bring the tops back in of course.
you may not need shorter uppers, the angle will be increased so that pulls the upper ball joint in
Bump steer I've seen mention of tall tie rod ends not being a complete fix. What about lowering the idler arm and steering gear (box)?
a stock second gen has toe In during dive, the opposite of a first gen which has toe out. Toe in is not as unstable so it' isn't felt as much but it affects turning (Ackerman). A taller spindle on a first gen increases toe out in dive due to the instant center moving closer to the car's centerline. I haven't looked at what happens to a second gen Camaro.
Overall it seems very doable. What am I missing?
Caster, you need to increase positive caster with tubular A arms or relocate the upper A arm rearward nearly an inch so you can set caster at 6 to 7 deg positive. Caster will do more for you than camber gain because caster helps more the sharper you turn the wheels. ...

[Rod]

there is no guldstrand mod for the 2nd gen camaro

[D-Man]

Thank you, Dave. It's great to have someone step in that gets what I'm going on about.

Yes, I will notch the frame for more upper arm clearance and use aftermarket upper and lower A-arms for more caster.
As I understand it some caster built into the lower arms as well as uppers helps keep the tires from contacting the back of the wheel well.

I saw that the arms will hit the frame quickly. Frame will get notched for more clearance. If needed I can add internal gussets to the frame while I have it cut open for extra strength. My problem has never been under-building. lol.

Incidentally, I found some great 2nd Gen info on your website today. :) Including the use of tall lower ball joints which I hadn't really considered. http://www.pozziracing.com/second_gen_camaro_tall_bal.htm
Back then you estimated around "1/8" of toe-in at 3" of bump with both tall upper and lower BJs with both ends of the linkage adjusted all the way up. So not bad, but sounds like I *will* need frame mods for additionally linkage adjust-ability if I do the g-mod as well. Basically, moving the mounting holes by welding in DOM sleeves.

On the SC&C website I saw that they're including tall upper ball joints (I assume + 0.5") with their 1.4" AFX spindle and A-arm kit for 2nd Gens. So it sounds like a 1.9" total increase over stock. Yikes.

If 1.9" is correct and desirable it means I would need to run tall upper and lower ball joints as well as the G-mod to get the same amount of camber gain. What do you think....is that crazy talk? You mentioned ackerman. Will I eat tires on the street?


there is no guldstrand mod for the 2nd gen camaro

Actually there is. Guldstrand would even mail you the template.

[79T/Aman]

the Guldstrand template was for a first gen if I recall on second gens all you did was cut the mount off, shorten it and re-welded it to the frame, as for the extra anti dive I feel it is not necessary these days with the type of brakes and shocks available, there already is anti dive built in from the factory.
I also feel the 1.9" taller for a second gen spindle is also too much and induces too much jacking, 1/2-1" is plenty depending on other variables.
There is also the matter of KPI angle that plays a roll in this.

[D-Man]

the Guldstrand template was for a first gen if I recall on second gens all you did was cut the mount off, shorten it and re-welded it to the frame,

In the article they were using stock a-arms (see picture) so moved the entire mount back for move caster and possibly to hide it from the sanctioning body.


as for the extra anti dive I feel it is not necessary these days with the type of brakes and shocks available,


Wouldn't modern 13-14" brakes, being so much stronger, make dive worse?



I also feel the 1.9" taller for a second gen spindle is also too much and induces too much jacking, 1/2-1" is plenty depending on other variables.
There is also the matter of KPI angle that plays a roll in this.

I'm wondering if that's a typo on the SC&C website. Have you ever ran the 1.4" AFX spindles?

[David Pozzi]

You need to be analyzing the roll center movement with software. I’d be trying for 40% Anti-dive but it can vary depending on your strategy.

[D-Man]

I'll look into that. Thanks Dave.