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greebly Mon Jul 11, 2016 5:50 pm

I have searched and there is ancillary information all over the place on ride heights with various springs but posters rarely identify what platform they have. Has anyone determined what the spring rates are to color codes to model year to model type? I know that the carat springs are lower, and supposedly the 85 models are the highest stock, but are there differences between tintop and camper 2wd models?

dougass Sat Nov 14, 2020 11:53 am

Bumpity bump bump.

One of my rear Weitec springs snapped and now Iím searching for alternative lowering springs.

The Weitecs were great, nice and level front and rear. I load up a bit when traveling so I bet my trunk is a little heavy for the springs.

H&Rs are going to be the cheap and easy option, but I am considering Eibachís race springs if I can figure out the math on length & spring rate.

Any input here is appreciated!

MarkWard Sat Nov 14, 2020 11:56 am

If you have access to a drill press and a scale that can read pretty high, you place the spring at the free height and then compress it exactly one inch. The reading on the scale is the spring rate. All springs are rated at one inch of compression from their free height.

dougass Sat Nov 14, 2020 3:21 pm

Nope, limited access to equipment over here.

Really inquiring about spring rates & length that people have success with.
Or, does anyone have specs on what is already on the market?

For example, I have read something like 460lbs/in is stock carat spring rate, I donít know the length.

...I plan on measuring the good Weitec rear spring unloaded and loaded, and using some deductive reasoning to see if any of the Eibach spring could work.

MarkWard Sat Nov 14, 2020 4:08 pm

If you were happy with your old springs, a reputable spring company like
Hypercoil will evaluate your spring for you. They can also make recommendations.

mikemtnbike Sat Nov 14, 2020 6:01 pm

Iíd consider calling Burley and see what he recommends for Weitec replacements.

Schwenks were a great upgrade for me from stock GL springs, but they had even more lift than I expected.

MarkWard Sat Nov 14, 2020 6:46 pm

An 8Ē spring is an overall unloaded height. A 12Ē spring is an overall unloaded height. Use your free height for comparing different springs. Obviously a stiffer spring will deflect less when loaded.

Without a way to measure your current spring rate, you really are guessing. Plus, everyone has different preferences.

You may pay more buying from a vanagon specific vendor, but you are paying for their homework. But they should get you close. Iíd be surprised if Burley or any other vanagon shop would give you proprietary info. Realize they arenít making springs. You could also look for a local speed shop to bring your spring to be measured. We do stuff like that all the time.

You then can order a correct spring on your own from whomever you want.

hans j Sat Nov 14, 2020 8:53 pm

Without knowing your corner weights either makes it tough to decide on springs.

Through my research, I can tell you the VW engineers nailed it with spring rates. They are just about perfect for a comfortable ride frequency.

DuncanS Sun Nov 15, 2020 3:00 am

Hansj says the stock springs are perfect. Mine give a very harsh truck like ride. I want some softer ones as my wife has a bad back and doesn't have much fun in my '91. We would like to do more camping, but roads here get badly trashed with frost heaves. Put in new gas shocks, but didn't help.

Suggestions?

Duncan

MarkWard Sun Nov 15, 2020 6:11 am

Gas charged shocks add about 75 pounds of spring rate. So, that would stiffen the ride some. Both our vans have stock springs with Bilsteins to control them. Canít really comment on stiffer or softer springs or Higher and lower ride heights
A progressive rate spring should give a smoother ride, but stiffen in the bumps.

hans j Sun Nov 15, 2020 11:01 am

Shocks and springs are a matched pair, and should be matched to the vehicle weight as well. A harsh ride could be contributed to shock valving. Aftermarket springs and revalved stiffer shocks won't help soften up the ride much.

Suspension tuning is extremely subjective and hard to communicate without test driving everything. I've driven most setups and I have an all stock carat with stock Boge emulsion shocks and it drives pretty nice. But I like a firmer ride. My syncro westy has softer than stock springs and way stiffer than stock custom Bilsteins. It drives very comfortably, closer to a modern car. The "feel" or how comfortable the ride is, is directly related to ride frequency.

The math and measurements of the vanagon suspension and stock springs show the engineers built it right.

DuncanS Sun Nov 15, 2020 3:01 pm

My understanding is that shocks only control the rebound after the spring is compressed. Is that true? My problem is we feel every tiny bump and road imperfection. If I hit railroad tracks, even at slow speeds, the car is thrown vertically quite suddenly. Coffee jumps out of the cup. It feels as though we don't have springs at all, just the body mounted directly to the axle. I got the gas struts as Dan at BD told me there were what I needed for a softer ride as oil filled are firmer. True? How about tire pressure. Orly '91 wears Nokia all weather 205 65 16's.

And you say your Westy has softer springs and drives more like a modern car. Orly is a daily driver and that's what I want even though it gets used as a truck and mobile tool shop as well. How does one find softer springs and how much softer?





Duncan

vanagonjr Mon Nov 16, 2020 5:00 am

DuncanS wrote: I got the gas struts as Dan at BD told me there were what I needed for a softer ride as oil filled are firmer.
True? How about tire pressure. Orly '91 wears Nokia all weather 205 65 16's.
Duncan
If those gas shocks (not struts) are KYB, then thatís part of the reason for a crappy ride. I remember a rally guy joking that KYB = Kill Your Back

What are you running for tire pressure. VW specíd a low tire pressure on the 16Ē models and I believe even the (14Ē) XL tires on alloys were lower than what most run. Do some research on that.

MarkWard Mon Nov 16, 2020 5:13 am

Shocks control compression and rebound of the spring. Road feel increases as you stiffen the suspension. Many like road feel. Others would like something that floats like and old Cadillac. The van pictured above looks pretty loaded. As the spring compresses, it becomes stiffer. So a 400 pound spring compressed 1 inch is an 800 pound spring compressed 2 inches. Plan accordingly.

DuncanS Mon Nov 16, 2020 6:18 am

The struts are Orig Equipment German Boge/Sachs according to BD. The loaded pics are unusual. Most of the time there is nothing. or a sheet of ply and a couple of 2 x's. No seats besides the front two. I weigh 170. Camping gear can't exceed 200 evenly distributed in the back. Will try and let some air out of the tires.

The boat is skin-on-frame and weighs 45 pounds with oars, sails and cushions. This is a more normal load. The other pics were taken to show how diverse the use is. As a daily driver there is rarely much aboard at all.


Duncan

Oh, and the front seat is out to allow the boat at 12'4" to fit with the hatch closed and 3/8" to spare. Thus in this pic the seat must offset the boat so no load at all.

4Gears4Tires Mon Nov 16, 2020 6:23 am

DuncanS wrote: My problem is we feel every tiny bump and road imperfection. If I hit railroad tracks, even at slow speeds, the car is thrown vertically quite suddenly. Coffee jumps out of the cup. It feels as though we don't have springs at all, just the body mounted directly to the axle.

I have driven a car with a frozen front strut. Trust me, the van is not that bad. That is truly a singular experience.

However, I do agree. The suspension feel on the van is not what I would consider supple. The issue is, like all things, physics. The van is very tall and it has a lot of ground clearance. If you put soft suspension on, it will bob around like a jack in the box. This is not what you want for stable driving.

My e39 (which I just sold, RIP) has Bilstein PSS suspension. It is both softer and firmer than the van. You don't get that crashy feeling. It's supple on that initial hit and very laterally stable in high speed turns. I don't know enough about suspension design, but since I know it's possible to have both a softer and a firmer suspension than the van I often wonder how I can improve the vans driving experience.

I updated the suspension on my bike over the summer and was blown away by the difference going down rock gardens. So I wouldn't be surprised if we just need better shocks. The Fox Factory shocks on my bike can adjust compression and rebound. (I think rebound is adjustable because my bike fork uses an air spring. On the van, we use coil springs which are not adjustable.) Go Westy offers a set of Fox Performance (one grade lower than Fox Factory) shocks and I wouldn't be surprised if this totally transforms how the van feels on the road. https://www.gowesty.com/product/-accessories/23676/fox-shock-absorber-set-?v=

They offer the Syncro set in 2 versions. https://www.gowesty.com/product/-accessories/23503/fox-shock-kit-for-syncro-?v= The more expensive has adjustable low speed compression. Dialing this way down is going to make your around town potholes and train tracks driving experience super plush. However, it will also make the suspension feel more sluggish and will roll more on turns.

dobryan Mon Nov 16, 2020 6:33 am

Duncan,

What is the max tire pressure for the tires on your bus and what tire pressures are you currently set at?

Your harsh ride issue can be solved.

MarkWard Mon Nov 16, 2020 7:05 am

Think of when you toss a stone into the water. The ripples move away from center, but the last ripples have the least energy. A spring behaves similarly. Without shocks, hitting a bump the spring compresses and rebounds and repeats, losing energy each oscillation. What the shock should do is to dampen and absorb these oscillations. Adjustable compression and rebound let you ďtuneĒ the spring oscillation. Adjustable shocks are not for me. I have no desire to tune on my vans suspension. We just drive it. Even the Penske shocks on my race car are rebound only adjustable. I worked with the engineer to get the valving correct. At Sebring or in the rain, I back off the rebound.

On a van, personally I canít imagine chasing the setup.

Abscate Mon Nov 16, 2020 7:53 am

Duncan , no wonder you are having trouble with two bears in the back.

Anyone in the NE has loose springs the ]y would like mapped Iím set up to do that

DuncanS Mon Nov 16, 2020 10:21 am

42 pounds of air. I can try and let some out and see what happens. Couldn't find any info on pressure for the tires. Printed on the side where it says Tyre Pressure there are a whole bunch of categories. 200. 220. 240 and so on. Is this the tire/tyre width? If so they say for 200 it should be 29 psi and for 220, 32. These numbers seem way too low to me, as extrapolating for 205 it would be about 30psi. Certainly wouldn't go that low unless someone who knows tells me.

Duncan



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