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Sat Jul 11, 2015 6:30 am

Sorry this has probably been asked before but I can’t find it. How much travel can I get from a vw king link front end if I change the shocks and towers ??

Sat Jul 11, 2015 9:12 am

9 ish inches, depending on how the beam is mounted. In a beetle with stock steering the long tie rod end will hit the tunnel before you get that much travel.

Sat Jul 11, 2015 10:46 am

Thanks takotruckin its for a rail I’ll try a get some pic’s up tomorrow

Sat Jul 11, 2015 3:00 pm

10-1/4" of travel in my Baja Bug. Original 58 beam, arms and spindles. 8" travel shock on tubular upper shock mounts which place the shock similar to the common 8" towers, though mine are a little to the rear of the common towers. Stock lower shock mounts on the arms are used. Similar setup on my buggy using the common 8" towers.

Stock stops trimmed and gusseted, with 1/4" contact pads on the ends.

The shock function at full droop is minimal. But in that range of the travel, the shock is not really needed anyway. And this allows for a smoother ride instead of being harshly stiff.

Mon Jul 13, 2015 3:55 am

Had a play yesterday. Max travel I can get is 7 inches, after that on full drop the shock hits the arm or on full compression the bottom shock mount hits the shock tower. I’m using off the shelf shock towers. I think if I moved the top shock mount back about an inch and maybe move the bottom mount I may just about get 10 inches
Sorry the pic’s aren’t very good

Mon Jul 13, 2015 1:19 pm

Your pictures don't show it, but which way do you have the shocks mounted? As you can see in my pics above, I have the shocks mounted so the body is up, and the bare shaft down.This allows a great deal more travel than if the shock body is down. Many shock manufacturers want the shock body down and the shaft up, I suppose to reduce leakage past the seal, I can't think of any other reason to mount them that way. With KYB Gas-A-Just shocks I've never had any issue with them body-up. My friend has had Rancho shocks on his rail for decades and has had no issues with having them mounted body-up either.

Tue Jul 14, 2015 5:07 am

Depends how they're constructed internally, it's not the seal pack as such as that sees pressure from the damping action regardless.

If they are twin tubes they usually need to be body down otherwise you'll draw air into the damping chamber, monotubes without divider pistons (emulsions) need to be body up or your damping piston will hit the gas pocket near full droop, monotubes with dividers don't care, run either way up, like your KYB's.
The Rancho's depend on the model really, the lower end stuff should be body side down.

As always there's the odd exception to that - twin tubes with gas bladders, monotube emulsions where the gas is held in the bearing pack - but as a rule of thumb it works the vast majority of the time, most cheap over-the-counter replacement stuff will be twin tube and need the body down.

Tue Jul 14, 2015 9:04 am

Good explanation Phillip!

One of the best reasons for choosing KYB or Bilstein shocks is that they are both DeCarbon design gas shocks which have floating pistons separating the gas from the oil and no air pocket. Thus with the body of the shock mounted to the tower, the shaft allows a great deal more room for suspension travel than otherwise.

There are shocks like Fox or King or Sway-A-Way or even high-end model Bilsteins which are even better, but far more expensive. For recreational offroading, KYB Gas-A-Just or the lower price Bilsteins are better bang for the buck.

Tue Jul 14, 2015 9:20 am

Some of the lower end Fox/King/SAW's are emulsions however, so still need to watch the mountings - our front Foxes were but I modified them as the heat was becoming an issue - certainly nothing wrong with the Billy's or KYB's though as you say

Tue Jul 14, 2015 9:41 am

PhillipM wrote: Some of the lower end Fox/King/SAW's are emulsions however, so still need to watch the mountings - ...
Yes they are, but they are all intended to be mounted cylinder-up, so they still fit like the KYBs and Bilsteins and work fairly well.

Tue Jul 14, 2015 12:13 pm

Thanks for the advice guys. On full compression it’s the bottom mount that hits the top arm but on full drop it may help to turn the shock over but I think it would still only give me 7 ½ inch max of travel. I think I need to move the top mount to get 10 inches and I think if I moved the bottom mount I could get up to 13 inches
At the moment I’m happy with 7 inches travel I’ll get the rest of the rail built and have some fun with it, then come back to the front end later
Thanks again guys at least I know were I’m going with it

Sat Jul 18, 2015 8:09 pm

Richard, I am puzzled about your 10.25" of travel. If you are talking wheel arc travel, then sure. Vertical travel, I have a hard time believing that. Stock arms are 150mm long, or about 5.9 inches. To get that much vertical travel, your looking at about 120 degrees of swing in the arms! :shock: :shock: :shock:

I did some hacking, cutting, and rotating, and got 80 degrees of rotation in my arms, and that puts me at 8.13 inches of vertical travel, which is easy to do. But 10.25? That's an extra 40 degrees of swing in addition to what I got in order to get that kind of number. I would like to know how you measured your suspension, cause that number sounds a little optimistic.

Mon Jul 20, 2015 10:25 am

Vertical travel. Not arc. Tape measures with their curved blades generally do not work well for measuring arc motion.

Perhaps I'm willing to allow more droop than you are. At that, the link is never close to going over center or the arms close to making contact with each other. The stops are set so the shock cannot bottom out or top out. And while the shock shafts are wiped clean very near to the end, the car has never yet since modifying the suspension bottomed out. Nor do I use the bizarre illogical lateral angles on the shocks that your compatriot PhillipM uses.

Mon Jul 20, 2015 12:11 pm

Nothing illogical about it - far more illogical is the mindset of 'shocks must be fitted to be rising rate and at 90*' - no matter what other factors come into your suspension :wink: :lol:
If you want illogical go look at the dozens of cars on here using a flexy hoop as a shock mount instead of a stiff, straight tube... :twisted:

Don't think 10" is too far out with stock arms though - it really depends on how far you let the droop go, and what size your front wheels are - I only get about 13" with the longer arms because the castor goes to pot if I get the last bit of droop travel, and I only run 29" front wheels (for lower unsprung weight), so I loose out on an inch or two of bump compared to most over the pond running taller wheels.
When it was on the stock arms were about 8-9 inch IIRC.

Tue Jul 21, 2015 1:16 pm

We've argued that point on this and other forums Phil. You and I disagree. You like your intersecting arc concept, I do not. Let's not revive the dead horse just to flog it some more.

I definitely agree that many shock mounts seen on here are not very good. But few of them threaten heim joint binding or lateral forces on shocks nor complicate shock valving unnecessarily.

Nor does wheel or tire diameter enter into wheel travel. That affects ride height and a number of other factors which have nothing at all to do with wheel travel.

I would like to see the interference which is limiting travel on BugTub's car.

Tue Jul 21, 2015 3:09 pm

1 - You brought it up.
2 - There's no side force on the dampers. Not unless your hiems are knackered and sieze up. Grab hold of a droplink by just the balljoint at either end and bend it without taking the joints to the limit of their travel to do it. If you do, I'm renaming you Clarke Kent.
3 - My shock valving is MORE linear than your straight up and down version. Not less. You'd realise that if you actually considered the forces rather than getting stuck on the 'must be progressive or nothing!' setup.

4 - How on earth can you say tyre sizes don't factor into suspension travel? They set how much compression travel you can have just by virtue of ground clearance, you can't have the spindle stuck through the top of the rim, shifting it inboard compromises the geometery - and compression travel past where the floor of the car is grounded isn't very useful outside of rock crawlers...If I fitted 33" wheels I could shift the bumpstops and take another 2" more travel, as the arms are nowhere near the same angle as they are in droop - same if I shifted up at the rear.

Tue Jul 21, 2015 4:19 pm

PhillipM wrote: 1 - You brought it up.
2 - There's no side force on the dampers. Not unless your hiems are knackered and sieze up. Grab hold of a droplink by just the balljoint at either end and bend it without taking the joints to the limit of their travel to do it. If you do, I'm renaming you Clarke Kent.
3 - My shock valving is MORE linear than your straight up and down version. Not less. You'd realise that if you actually considered the forces rather than getting stuck on the 'must be progressive or nothing!' setup.

4 - How on earth can you say tyre sizes don't factor into suspension travel? They set how much compression travel you can have just by virtue of ground clearance, you can't have the spindle stuck through the top of the rim, shifting it inboard compromises the geometery - and compression travel past where the floor of the car is grounded isn't very useful outside of rock crawlers...If I fitted 33" wheels I could shift the bumpstops and take another 2" more travel, as the arms are nowhere near the same angle as they are in droop - same if I shifted up at the rear.

1. Yup...I brought your name and your oddball way of doing shock mounts into this discussion. I accept responsibility for that foolish error.

2. There is no sideforce on the shocks unless the heims reach and try to exceed their limit of angle in the shock's travel. With conventional single plane shock mounting, this is not even possible. With your 2-plane shock mounting it is not only possible, but you probably come rather close to achieving it. By the way, the OP's heims are NOT knackered. He's not using heim end shocks. He hasn't yet shown us what shocks he IS trying to use though. Heim ends are very doubtful though. And rubber bushing shocks REALLY don't like lateral angles.

3. The 'must be progressive or nothing!' concept is entirely one of your introduction. I've not mentioned it. I DID mention rising rate in another discussion of VW beam shocks (shock rates are actually either rising, falling or neutral depending on which part of the arc of the lower shock mount) elsewhere on another forum where I was trying to simplify discussion for the sake of another member who had expressed that he did not understand all of the complexities of the issue. You chose to complicate that discussion for the poor fellow. Let's please not do so here.

4. With stock VW linkpin arms, if one were to travel the suspension to the impossible point of the arms pointing straight up from the beam, the spindle would still have a radius to the ground far less than the radius of a 26" diameter tire. I don't expect offroaders to use a tire smaller than that on the front. Slalom competitors might. Perhaps you are expecting some might use leftover 10" Tyrell P34 F1 tires that have survived decades of Mini road racing? Decades ago, I used 165-15 tires on the front of my Baja. They were 26" tall. I don't expect smaller than that. And as I said, such a trailing arm position is impossible. The bare 15" rim will not make it to even with the bottom of the beam before the arms take the link too far. That's how I can "say tyre sizes don't factor into suspension travel".

Now Phillip, can we get back to the OP's issues?

Tue Jul 21, 2015 4:29 pm

We can yes, but your counterpoints still make little sense, if it bugs you that much that my shocks are at another angle to yours, start a topic and explain it, instead of the constant snide references.