Trying to Minimize Bumpsteer

[SactoJim]

On my 72 I have an "old school" type drop on the front with stock spindles, stepped A arms, and drop springs. Downside to this (stock spindle) is I have too much bumpsteer for my liking.

Looking at it, it seems it would help quite a bit if I could flip the tie rod over on the spindle mounting point. I know that the spindle mounting hole and tie rod end stud are tapered and was wondering if anyone has ever messed around with this and had some "not too involved" success.

[bagged69chevy]

I drilled mine out with a 9/16" drill bit; removing the taper completely. Then i replaced my stock type tie-rod ends, with heim joints with a 9/16" center bore. Worked perfectly.. just make sure you use a lock washer or a nylon nut with your bolt. I wouldnt suggest removing the taper from the spindle if you plan on keeping the stock tie-rod end.

[bagged69chevy]

Another comment.. You should NOT be experiencing any additional bump-steer unless you've changed your arm lengths, mounting positions, or steering mounts or lengths.. (just adding lowered a-arms and drop springs should NOT change your geometry) If you basic geometry is the same as stock (just lower) its not worse off than it was from the factory. Now I'm not saying that the factory setup doesn't have any bump steer, but its better off than some custom trucks driving down the road today.

I designed my suspensions from scratch, and i have 14 inches of front suspension travel, and less than 1/32" bump-steer through the entire arch of the suspension.

[hotrodhomi]

i had the same suspension on my blazer before I bagged it. It also had bumpsteer. If you don't want to bag it I would suggest stock arms with drop spindles and lowered coils.

[SactoJim]

Originally Posted by bagged69chevy

Another comment.. You should NOT be experiencing any additional bump-steer unless you've changed your arm lengths, mounting positions, or steering mounts or lengths.. (just adding lowered a-arms and drop springs should NOT change your geometry) If you basic geometry is the same as stock (just lower) its not worse off than it was from the factory. Now I'm not saying that the factory setup doesn't have any bump steer, but its better off than some custom trucks driving down the road today.

I designed my suspensions from scratch, and i have 14 inches of front suspension travel, and less than 1/32" bump-steer through the entire arch of the suspension.

I'm far from a suspension expert, but by using a modified A arm, drop spring, and the stock spindle, I've pushed the tie rod mounting point farther up in it's travel arc and as the suspension compresses and extends it has a more dramatic affect on toe. As the suspension compresses, the tie rod end is pulled towards the middle of the vehicle and vica versa when it extends.

Seems to me that the more perpendicular the tie rod is to the wheel, the less pronounced the change in toe will be as the suspension travels up and down. My tie rod angle is pretty dramatic when compared to the A arms and far from perpendicular.

I only come to this conclusion by looking at it and visualizing what happens and also sketching it out in a CAD program.

Ideally, I'd redo the front suspension, but I was just looking for a quick fix....or semi fix.

[crazy longhorn]

Yea, your bump steer is due to the angles on the tie rods. You can get by with about 3" on a spring.....but add the dropped arm to the mix & the trouble starts. I saw a kit (DJM suspension IIRC), that drills the spindle, taps & installs an insert(with locktite) to flip the tierod over the top side of the spindle. This should correct the bumpsteer issues, & retain the stock pcs. I havent tryed it , but looks like it should work to me Best of luck,crazyL

[SactoJim]

Originally Posted by crazy longhorn

Yea, your bump steer is due to the angles on the tie rods. You can get by with about 3" on a spring.....but add the dropped arm to the mix & the trouble starts. I saw a kit (DJM suspension IIRC), that drills the spindle, taps & installs an insert(with locktite) to flip the tierod over the top side of the spindle. This should correct the bumpsteer issues, & retain the stock pcs. I havent tryed it , but looks like it should work to me Best of luck,crazyL

Thanks CrazyL.......I'll see what I can find.

[bagged69chevy]

Im not trying to argue with you guys.. but You are not changing the mounting points for the suspension.. Yes the A arms have a drop bucket on them for the spring to mount in, and yes you added a 3 inch drop spring.. but all the original mounting points are the same. So the over all geometry is exactly the same.. the suspension is just more compressed than usual. Even if you add a drop spindle into the mix, the steering mount on the spindle SHOUld be in the same point as stock. Its all about your intersects for your suspension. If all those stay the same, you geometry will be the same. no matter how low or high the suspension is. .You might be noticing more bump steer since the suspension is more compressed than usual. I believe on these trucks, in the "sweet spot" of the suspension (usual driving travel from stock) you hardly notice the bumpsteer, but since your suspension is compressed 5-6" more from stock, the bump steer will become more evident. If you get rid of the lowered a-arms, and replace them with drop spindle, you will see a great improvement.

I'm not suspension expert either, but understand suspension geometry and have designed my fair share of front suspension for streetrods.

[crazy longhorn]

Originally Posted by bagged69chevy

Im not trying to argue with you guys.. but You are not changing the mounting points for the suspension.. Yes the A arms have a drop bucket on them for the spring to mount in, and yes you added a 3 inch drop spring.. but all the original mounting points are the same. So the over all geometry is exactly the same.. the suspension is just more compressed than usual. Even if you add a drop spindle into the mix, the steering mount on the spindle SHOUld be in the same point as stock. Its all about your intersects for your suspension. If all those stay the same, you geometry will be the same. no matter how low or high the suspension is. .You might be noticing more bump steer since the suspension is more compressed than usual. I believe on these trucks, in the "sweet spot" of the suspension (usual driving travel from stock) you hardly notice the bumpsteer, but since your suspension is compressed 5-6" more from stock, the bump steer will become more evident. If you get rid of the lowered a-arms, and replace them with drop spindle, you will see a great improvement.

I'm not suspension expert either, but understand suspension geometry and have designed my fair share of front suspension for streetrods.

I have to agree that a stock lower arm/dropped spindle will work much better with the lowered spring, than the stepped arm/spring combo. crazyL