Shocks

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RussellK
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Post by RussellK » Fri Jul 13, 2007 7:24 am

I bough cheapo Oil filled shocks for the rear 3 years ago but never put them on until last week. I need to do the front too. I know Koni are great but I would have to buy front and rears from Bus Depot. That's over $400 I can get just the front in the Boge and leave the rear with what I have but is that a bad idea? Should I just suck it up and get rid of the rear oil filled and go Koni all around or even Boge? Would there be that much difference in ride and handling between the Boge and the new oil filled in the rear?
-Russ

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Post by mattg » Thu Jul 26, 2007 10:16 am

My new shocks are on and I am enjoying the ride. The biggest improvement seems to be handling in the wind. I have the heavy duty oil filled boges and they are a nice upgrade to the old monroes that were there before.
I'm all out of ideas and I've tried nothing.

77 Westy 2.0 FI

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DurocShark
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Post by DurocShark » Thu Jul 26, 2007 10:20 am

Yeah, after having KYBs and Konis I can say I really feel the difference between gas and oil. With the KYBs, regardless of the setting, the bus feels like it's truly damping shocks, whereas the gas shocks seem to transmit each little jolt.

If I didn't have the Konis, I'd definitely put a different oil-filled shock on.

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spiffy
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Post by spiffy » Tue Oct 02, 2007 7:27 am

Anyone tried the GR-2's on both the front and the rear or is the preffered setup go with the gas adjusts in the back and the GR-2's up front?
78 Riviera "Spiffy"
67 Riviera "Bill"

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Ryno
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Post by Ryno » Tue Oct 02, 2007 7:40 am

spiffy wrote:Anyone tried the GR-2's on both the front and the rear or is the preffered setup go with the gas adjusts in the back and the GR-2's up front?
I'm running the GR-2's on all four corners, my bus gets a little spooky at 65mph in a stiff crosswind but I'm not running heavy duty tires or a rear sway bar yet.
Ryan

1985 Westfalia

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Amskeptic
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Post by Amskeptic » Tue Oct 02, 2007 9:15 am

Thirstytank wrote:I'm running the GR-2's on all four corners, my bus gets a little spooky at 65mph in a stiff crosswind but I'm not running heavy duty tires or a rear sway bar yet.
Don't get all excited about rear "sway" bars. They are not to be installed as a "cure" for lack of directional stability. That is not what stabilizer bars are for. These cars are designed to lean at the rear so the front stabilizer bar can unload the inside front wheel during emergency maneuvers. Stabilizer bars are designed to reduce traction at the axle they are installed on. Feel free to install tires with decent sidewall rigidity, but don't second-guess the factory engineering like so many of us do.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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vwlover77
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Post by vwlover77 » Tue Oct 02, 2007 9:29 am

Were they shooting for understeer at the limit? Given the nature and purpose of the vehicle, I would think so.
Don

---------------------------
78 Westy
71 Super Beetle Convertible Autostick

"When we let our compassion go, we let go of whatever claim we have to the divine." - Bruce Springsteen

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Ryno
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Post by Ryno » Tue Oct 02, 2007 10:04 am

Amskeptic wrote:
Thirstytank wrote:I'm running the GR-2's on all four corners, my bus gets a little spooky at 65mph in a stiff crosswind but I'm not running heavy duty tires or a rear sway bar yet.
Don't get all excited about rear "sway" bars. They are not to be installed as a "cure" for lack of directional stability. That is not what stabilizer bars are for. These cars are designed to lean at the rear so the front stabilizer bar can unload the inside front wheel during emergency maneuvers. Stabilizer bars are designed to reduce traction at the axle they are installed on. Feel free to install tires with decent sidewall rigidity, but don't second-guess the factory engineering like so many of us do.
Colin
I'm not all excited :king: , I've driven a bus with the sway bar upgrades and the HD tires and liked what I found. Now if they made those tires with whitewalls, I'd be a happer camper.
Ryan

1985 Westfalia

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Amskeptic
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Post by Amskeptic » Tue Oct 02, 2007 5:36 pm

vwlover77 wrote:Were they shooting for understeer at the limit?
Indeed. It is considered the safer alternative to having the rear end pass you by. Take any corner or evasive maneuver as an example and visualize it in s-l-o-w---m-o-t-i-o-n. The first turn of the steering wheel and your vehicle's inertia will resist you right off the bat. This is initial understeer. As the vehicle responds to your input, energy stores up in the suspension as it loads on the outside. The inertia is naturally carried rearward in the vehicle's chassis at the apex point of the curve where you then unwind the steering wheel to exit the curve. It is the apex-to-exit that oversteer rears its head. With a front stabilizer bar, the energy is released by front outside wheel slippage. But what about trailing throttle oversteer? Indeed, any late braking or middle-of-the-curve braking you would expect a transfer of momentum to the front to give you some extra understeer tendency, right? Well. Wrong. Now that your rear-engined car is committed to the corner, the rear outside tire is all at work trying to keep the engine/driveline mass going around the corner. Any additional request, like braking, will overwhelm the rear wheel and you will lose traction. Independent trailing arm rear suspensions like our VWs and BMWs and Mercedes and Porsches all have a nasty tendency to let it out at the rear if you even think of braking or slowing mid-corner (right, BobD?) Mild maintenance/acceleration will help keep the rear suspension planted, and if you have swing axles like the early VWs and Corvairs and Mercedes, definitely err on the side of acceleration. . . after the apex.
Now, about that energy stored in the suspension. In an evasive maneuver, the natural rebound of the outside suspension will "throw" the car back to the other side after your initial change in direction is absorbed. You so want the rear suspension of the VW to acquiesce to this rebound. You would also like the front suspension reject it. A rear stabilizer bar will merely toss the load directly to inside rear wheel which will shortly become the outside as you overcorrect and send the car into the weeds. If your rear suspension is allowed to MOVE and the car tilts dizzily, the better your chances of the front end getting loose and helping you regain directional stability.

But no. We have subjective sensations that perturb us, "my car leans too much, I am afraid it is going to tip over," or after monster stabilizer bars are installed "hey now, this baby steers through corners like it is on rails man, it really HANDLES now." but the actuality lurks under the blather, ready to screw you when you have a true need for emergency/evasive handling. Changing the suspension componentry/balance because you "like the way it feels now" is not what matters when the shit hits the fan.

The rules of handling/performance driving as it relates to these cars:

Never Slam On The Brakes! Squeeze them even in an emergency.

Reduce braking as your car enters a corner, be off of them all together at the apex. Accelerate gently at the apex and progressively out of the corner (unless you really overcooked it where neutral throttle and a prayer is best, unless you have swing axles where you really need to keep the rear end down)

In an evasive maneuver, it is not the initial swerve that even matters. I mean yes, it is good that you missed the dog or child or car, but the real problem is the subsequent correction. It may seem unlikely to remember or execute but please try to allow your car to stay on its new course, don't try too terribly hard to get back into your lane or even back onto the road to keep it all tidy. Just try to allow the new course, even if you have to mow down a few roadside reflectors. The surprise that bites you in the ass is the amount of energy stored up in the suspension as it bounds back from your initial swerve.

Just because there is a marketing industry that wants you to festoon your car with gee-whiz gadgetry doesn't mean you have to fall for it. Think about your actual circumstances. There are people who have lowered, changed the spring rates, added roll-stiffness, and gotten away with a much better handling car when it was all over. Like Jake mentions with his engine configurations, "it is in the combination." We cannot just grab a piece of the transformation and add it ala carte to our cars. It is much more complicated and inter-related than that.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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regis101
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Post by regis101 » Tue Oct 02, 2007 7:29 pm

I'm on the KONI bandwagon. Have a thou or so on them.

I do like the adjustability. I do like that they can be rebuilt. The price is not an issue.

Running the Hankook RA 08 195's on Vanagon alloy wheels with Nates 2.5 spindles and one spline out back. There is about 4" from the top of tire to the wheelwell

The shock adjustment itself is just shy of two full turns. I had them on full soft in front and ~1/2 in back. The ride was nice, quiet and comfy. All was well with 1/2 tank and just me. Two people up front and/or some aggressive driving and the front would bottom easily. Nice ride quality, though. Better than my two other cars.

I now have both fr and rr at 1 1/4 turn. The ride equates my KYB's. Still can bottom out. Almost the same as when the KONI's were on full soft.

So my issue is that is seems to me that KONI is rebound adjustable but not compression. If this bus/westy was at stock height I'd probably settle for 1/2 turn from soft fr and rr and enjoy the road.

I may pull one of the fronts to make sure I know what I'm talking about with the rebound/compression thing.

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Amskeptic
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Post by Amskeptic » Sat Oct 06, 2007 5:44 pm

regis101 wrote: seems to me that KONI is rebound adjustable but not compression.
Your adjustment affects both compression and extension.
(edited 10/16: based on correspondence with Koni, regis101 states that the red Konis adjustments applies to rebound travel only)

Remember, these cars use the compression bump stops as part of daily suspension duty. They are called into play long before you think they are being used as actual "bump stops." They ought to be renamed as "progression dampers" because that is what they are there for, to give these linear torsion bars some progressivity. Look at the conical shape of the compression bump stops. Note the spring inside of the rear suspension bump stops. Expect to be hammering those babies frequently.
Do not use stiffer shock settings to ease the load on the bump stops. Your shock settings are best tested in corners that include a set of poorly maintained railroad tracks. If your bus steps sideways three feet, they are too stiff. Now go visit the tracks on a straight stretch, preferably with a serious change in elevation right at the rail bed. If your bus jounces more than once, they may be too soft. If you step sideways three feet and jounce more than once, you're driving too fast, you maniac.
Colin :joker:
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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regis101
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Post by regis101 » Sun Oct 07, 2007 2:13 pm

Cool. Good words.

My thoughts about the bus KONI's come from a shock dyno graph I 'member seeing about KONI vs Bilstein for the BMW e30 crowd. The Koni adjustables were rebound dampened only in that application.

When I get a chance, I'll email KONI to ask if the true bus shock technology escaped them or not for the last batch from busdepot.

Of a greater note is what you say about the bump stops. Indeed the conical shape of them vs the dish on the torsion is looking to marry, IMO.

I'n the end, I'm still very happy with them.

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Amskeptic
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Post by Amskeptic » Tue Oct 09, 2007 7:35 pm

regis101 wrote:My thoughts about the bus KONI's come from a shock dyno graph I 'member seeing about KONI vs Bilstein for the BMW e30 crowd. The Koni adjustables were rebound dampened only in that application.
.

IIRC, not just rebound dampened but rebound adjustable on the yellow performance shocks. Most double-acting telescopic shocks are designed to do their most serious damping on the rebound. But of course. Why have your shocks resist the initial impact with the 4X4 in the middle of the freeway? You want them to control the car after it wants to launch (rebound), not when the car is absorbing the initial impact (jounce).

Remember that the E-30 has those monster front coil springs with serious inner vibration harmonics (as any coil spring is want to have), our buses have internally quiet torsion leaves. But our trailing arms have lousy anti-dive brake control (you already know that), superior bump absorption, and not-good-at-all rebound control. It is just the physics of the trailing arms acting like huge levers. Put calipers on the far end of the levers and you have that famous VW bus dive to the ground during emergency braking. So charming.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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glasseye
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Post by glasseye » Wed Oct 10, 2007 8:22 am

Amskeptic wrote:I put on whatever gives me the best chance of maintaining control of the vehicle in an emergency.
Colin
I had no idea that shocks were a safety item until I lost both the Asstro's rear and front ends simultaneously on a straightaway with rough ice at highway speed. Wheel hop/chatter pitched the vehicle sideways enough that I was totally outta control. With oncoming traffic, there were at least five seconds of drama during which I said to myself "I'm not sure I can save this".

I bought four new shocks first chance I got.
"This war will pay for itself."
Paul Wolfowitz, speaking of Iraq.

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spiffy
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Post by spiffy » Wed Oct 10, 2007 9:05 am

FWIW I purchased (2) KYB Gr-2's and (2) gas adjusts(rear) from CIP1 for $150 and free shipping, as soon as I get them I will put them on and I should have a good report as I have some monroes on there now so those of you not wanting to go Koni should get a good idea of what to expect.
78 Riviera "Spiffy"
67 Riviera "Bill"

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