MMM ... 1965 Mustang Bumpsteer P & S ... MMM

[George Manont]

Hi,


I'm experiencing something call bumpsteering ( front-end swaying when hits bump )


I've tried to find a true correction practice but seems like I'm hitting the wall.


Any advices / experiences sharing are appreciated.


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[Bryce]

Is this stock suspension in the front?

I have a 65 falcon with my custom suspension and stock steering. and a 65 mustang with stock suspension, my coilover conversion and a TCP manual rack.

Neither car has bumpsteer. I was able to dial it out.

Bumpsteer is the toe in/out change when the suspension is compressed (bump).

What is your ride height? lowered?

with stock suspension and steering it is hard to adjust but some tricks are out there. Basically try to make your tierod parrallel with the LCA. The inner pivots are pretty good from the factory.

[George Manont]

Is this stock suspension in the front?

I have a 65 falcon with my custom suspension and stock steering. and a 65 mustang with stock suspension, my coilover conversion and a TCP manual rack.

Neither car has bumpsteer. I was able to dial it out.

Bumpsteer is the toe in/out change when the suspension is compressed (bump).

What is your ride height? lowered?

with stock suspension and steering it is hard to adjust but some tricks are out there. Basically try to make your tierod parrallel with the LCA. The inner pivots are pretty good from the factory.


Hi Falcon '65,


Yes, this Mustang is lowered by apprx. 1.5".

Steering system is now by rack & pinion. Tierod left side is parallel to the ground. Right side is slightly upward. Is this the root cause ? If yes, what's the best correction method ?


Thanks,


GM.


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[Bryce]

Three ways that I know of.

Simplest: put washers inbetween the spindle and tie rod ball joint. This will lower the BJ slightly. This is for small adjustments as the threaded portion may not allow you to space it down very much.

Buy the TCP bump stop eliminator kit. Comes with a taper stud adapter and rod end and new sleeve. Expensive but works. I think all parts can be sourced separetly for cheaper.

The way I did it: reamed the spindle to .495" and just used a rod end instead of a ball joint and bolted it to the spindle with the correct length spacer to make it parralel.

[NOGO]

It sounds like the rack and pinion setup you have is not installed or designed properly. Using springs to lower a car can also adversly affect bumpsteer, depending on the suspension setup.

[monteboy84]

It sounds like the rack and pinion setup you have is not installed or designed properly. Using springs to lower a car can also adversly affect bumpsteer, depending on the suspension setup.

+1

Everything you change on your suspension can have a serious impact for good, or for bad, I re-evaluate the R&P conversion that's on there. The tie rods should most definitely be horizontal, or at a minimum angled equivalently.

Bumpsteer in general will simply cause the front wheels to toe in or our when you hit a bump that spans the full road, but the asymmetry in your tie rods is likely what's causing the darting you've experienced.

[George Manont]

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Hi Falcon, NoGo & Monte,


Thanks much for your advice.


I'll try with Falcon's reco. I'll go with the adjustable rod-end.


I'll let y'all know the outcome.


Thanks again for your kind helps !



Cheers,



GM.



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[George Manont]

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Guys,


I appreciated all your recommendations / suggestions. After some deep study I said to myself I will take on the problem on “ Bumpsteering “ , based on knowledge I have gathered from you.


As I understand, in order to get out of the Bumpsteer issue, I must have the tie rod end level to the lower control arm.


Here’s how we’ve done to correct to issue ;


1. Level of the tie rod end in relation to the lower control arm. They are NOT in parallel. ( BEFORE picture )

https://static1.pt-content.com/images/noimg.gif (http://image.ohozaa.com/show.php?id=8f111edde837b7018c433a511c2fca44)



2. I bought a new tie rod end that’s a bit longer arm but still have the same strut height. ( Avoid using the wear-fast NAKED ball joint )

https://static1.pt-content.com/images/noimg.gif (http://image.ohozaa.com/show.php?id=05c091fb59115bbeaee4135c7a233084)




3. A spacer, made out of high grade steel, was made in the same shape … then fit OVER the standard strut. ( screwed on with locking pin in-placed )

https://static1.pt-content.com/images/noimg.gif (http://image.ohozaa.com/show.php?id=7e2eb5021f319896fad7f9edc45c3cae)




4. Installation needed some adjustment and patients.

https://static1.pt-content.com/images/noimg.gif (http://image.ohozaa.com/show.php?id=c9ccbefa85006645309aa4168a2c8c9c)



5. Level of the tie rod end is now in parallel to the lower control arm. ( AFTER picture )

https://static1.pt-content.com/images/noimg.gif (http://image.ohozaa.com/show.php?id=21b82f14e4f7f031fd1c38d195080181)




Driving is now firm. Almost all swervings, swayings are gone.


Integrity of standard ball joint is still there. ( vs. the NAKED ball joint that prone to be damaged easily / weared fast , as told by Deuce 454, thanks…Mr.D ! )



Thanks to you all !



GM.




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[latamud]

Wow, that's a significant drop, how does the other side look? Maybe the rack wasn't centered under the car?

[NOGO]

Your pics are not loading very well for me but it looks like you have a home made steering rack system that was not designed correctly and you put a band-aid on it. No offense but if the geometry is not correct (the easy part) then the safety factor is likely not up to standard either. I would opt for a proven steering rack system for safety sake.

[George Manont]

Wow, that's a significant drop, how does the other side look? Maybe the rack wasn't centered under the car?


The other side was OK. I didn't touch it !


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[George Manont]

Your pics are not loading very well for me but it looks like you have a home made steering rack system that was not designed correctly and you put a band-aid on it. No offense but if the geometry is not correct (the easy part) then the safety factor is likely not up to standard either. I would opt for a proven steering rack system for safety sake.


Thanks for the caution on safety. I'll have to live with it for now anyway.

On the pics uploading, this host was the best I could use. Photobucket has done me wrong when they started charging and w/o precaution...pic was lost during my business presentation. Bad news it was !


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[JRouche]

This is what I wrote on the other site......

I gotta say, very ingenious.. I like thinking outta the box.

I dont usually like to pick apart guys modifications. But when it comes to two systems, braking and steering I like to lean towards safety. You loose any of those two systems and there is some carnage in the future.

Sounds like you got a piece of "high grade steel" for the adapter. What exactly was the high grade steel and what was the heat treatment on it? I ask cause its a hex shape. I dont know why you used that shape. Im assuming you had a machine shop with heat treating capabilities make the adapter? Im hoping they didnt use a piece of stock that was machinable for the socket side and it wasnt heat treated.

It just worries me to see a hex shape in there when I dont see a need for the shape. Scrap stock on hand comes to mind. Not good.

Then more importantly. The original ball joint was NOT designed to take the additional loads that you are putting on it, the stud mainly.

Dont get me wrong. I love great fixes. And hate to hear all the nay-sayers. But with some critical systems I would like to throw out some simple advice.

The spacer? Is it the hex piece with a tapered bore for the original pin? Then how is the new tapered pin attached to the hex?

It just looks a lil scary to me. Im not sure I like that mod. JR

And Ill add some here. You say you will have to live with it for now. Ummm!!! You may not live long. I havent seen any detailed description on exactly how you made the connector. So for me it means it didnt have much in the way of engineering involved.

Id love to hear about the methods used to make the connector. And to be honest, I think whatever the methods were they will come up short.

Its not just your life you are jeopardizing when you have a weak steering system. The other folks on the road have to be considered also.

Id like to hear how the joint was made??

[George Manont]

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Hi JRouche,


That's a good education there, thanks for the tips.


It's prompted me to go back & have a look at the HEX material. I checked all the way back to the importer and received some assurance that it was meant for truck wheel fasteners, which can handle both torque and pressure. They also guarantee that the steel is as strong , or probably even stronger than the type use in the standard ball joint. ( Grade AISI 1035 - 1037 )


And I also did check the set up , things are as what we have installed. I will contibue checking as a routine .


On the HOW it was made. The " Spacer " is tapered inside with threaded to fit the standard pin , then this spacer was tightly screwed over the standard one , plus with safety pin inserted to prevent the unscrewing movement.



You are right that when we deal with this type of work the main concern is the safety espect, and that is why I didn't use the naked ball joints even they look more exotic but prone to wear fast.



Cheers,



GM.




BTW the certainty in this small world is hard to find, see the below pic of a damaged spline shaft, which passed through the hardening process and yet...has gone south !



https://static1.pt-content.com/images/pt/2010/02/2r3fr11-1.jpg




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[Bryce]

just curious, why was only one side altered. It seems like the rack is not symetrical.

[George Manont]

Hi Falcon65,

Good observation ! Yes, only the right side that needed some adjustment. I was convinced that the non-symetrical was a non-issue as long as the tie rod end level in sync with the lower control arm.

Judging from the driving result...the correction is right.

And the safety issue caution from members here is truly appreciated.



GM.

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[Bryce]

steering works best when both sides are the same. Ackerman and bump are affected from different length tierods that are at different angles. the rack should be centered and level.