"4-Way suspension" work alike?

[Piledriver]

Scored a new pair for a winnebago: Seem to have stiffer springs and shock valving as you would expect, but same otherwise.

Put them on my existing very soft front Monroes, a bit bouncy, will probably end up swapping the current est. ~100 lb/in rear set for the ~200 lb/in front setup. (need to actually measure these springs, the end castings are the same as is the spring ID)

I spaced the top out ~1/8" but it appears I didn't really need to.
Everything clears.

4way1.JPG

4way2.JPG

[Soul]

You commented that after installing the fronts that they were a little bouncy. Other than that what's your overall driving impression after installing on all four corners?

[ProctorSilex]

Where'd you score them?

[Piledriver]

You commented that after installing the fronts that they were a little bouncy. Other than that what's your overall driving impression after installing on all four corners?

Porsche.

Where'd you score them?

Ebay, again.

The T3 front was always a bit bouncy, the light weight makes it harder to spring and dampen I guess.
It swallows the big stuff now, but on the little stuff it's choppier than stock.
Didn't get around to swapping things F&R, so I'll be living with it for a week.

[Piledriver]

Swapped the springs F<>R Sat...
Now you would never know these were on the car just driving straight down the road, if anything it rides better than stock.
Time for the dry sump. (seriously, I have been looking for an excuse, and it could actually use it)

Following Helos suggestion, I Googled a bit and found a fine spring rate calculator that figures out what you HAVE based on dimensions...
http://faq.f650.com/FAQs/ShocksSpringRateFAQ.htm

Due to the number of free coils and different wire dia, it appears to work out to ~225 lb/in F & ~325 R.
(4 free coils front/6 free out back... assuming I'm counting right, at this time of the evening that's dubious)
The springs are 50mm ID, calcs are based on ctr to ctr dia.

I'm going to keep looking for a damping equivalence calculator (or such) if such a thing exists.
The counter springs act as heavy dampers, you should be able to calculate it.

Interesting link giving a hint what the current F1 tech in shocks is...
http://www.racecar-engineering.com/arti ... -j-damper/
Smells a lot like KERS.

[raygreenwood]

Pile, thanks for dragging me back to this discussion. That spring calculator is interesting....but in several instances takes a few things for granted. The comment about progressive coil springs being uniform in load with coil spacing only adding to it by virtue of coil bind....is only true...if the cross section and temper of said coil wire is identical.

For instance...on the rear coil springs of my old VW 412 wagon (yellow series)....the rear section of the coil...the load handling section...has coils closer together...AND those coils had been rolled while hot either before or during winding. I can attest to the differnt density by having cut coils from both ends of tehspring during experiments back in the 90's.

Their cross section is not round in the load control area...and neither in that respect is the spring steel density and response the same as the rest of the spring in the ride control areas. This is not unlike the effect you get when shot peening steel.

Here is just about the best repository of spring information I have ever seen...with calulators for virtually all spring types and all of the math and theory,
http://www.mitcalc.com/doc/springs/help/en/springs.htm

The interesting thing about the early four way coil overs I found is that they had not round wire but flat spring wire. Totally different load control and very similar to high tension die springs.....and mostly used for the fact that they work almost linearly from the at rest point ...when either pushed or pulled.


Another interesting feature that many do not realize…that is possible with the four way type shock and its unique mounting at each end….is that…if the attaching coil area milled into the mounting block at each end of the shock has enough winding space in it….and if you have a custom spring wound…..with a load control section in the center of the coil (close spaced coils)…with ride control (wide spaced coils) at either end or one end…..by loosening the end mountings and screwing the mounting areas inward…you not only shorten the effective coils that are operating….you shorten the entire shock (great way to adjust ride height) and start placing more load onto the load control coil in the center (which effectively progressively stiffens the spring rate…perfect for lowering).

This is so….because any coil section that screws into the helically milled mounting grooves at either end…is taken out of the equation entirely because it can neither compress or extend. It becomes effectively solid.

Now….in the old days…most of these shocks were single tube standard dampers. If you have one made internally like a Bilstein or a Monroe …that has progressively tapered bypass grooves milled in the wall of the bore dividing it into different response/ride control zones…..by changing the length of the shock by screwing the coil into or out of its end mounts…you effectively make an adjustable load range shock because your piston stroke begins in an area of more or less initial bypass damping. A high range of possibilities if planned for from the start.

Add to this possibility you can actually use two different spring rates….both linear or both progressive or one of each with a load perch in the middle….and start the whole process of end mount adjustment over with even more possibilities…..

So as a sanity check….yes the four way theory is different and unique…depending upon how the details are handled.


As for the J damper…cool…a new and cool application for use of this electromechanical damper in cars…..but nothing new really.

This is really just a passive linear motor. We use systems just like this is certain printing and coating equipment for effecting delicate control over tension in printing webs. You basically have a rack and pinion…..when nothing is running the rack…which is attached to a lever attached to a roller that bears on the printing web…is in the middle or neutral position.
Put pressure on the web….and the rack wants to move…and moves the gears. The shaft encoders, strain gauge and linear motor attached to the gear resists at a preset rate…acting as a brake at one setting…and as an active return force to bring it back to center. It can push and pull equally…or you can from the control panel….add more bias to one direction or another.

Going back 2-3 years to some of our original discussion points…the original transverse mounted spring dampers we mentioned that were used in the front and rear of some open wheel classes….were very similar to this and virtually identical in base theory to the “four way’ shock design.

What they all have in common is a starting “at rest’ spring state. Since these springs are designed to have similar forces when compressed or extended….they are built with end caps that keep them in the neutral state. They react to either compression or expansion equally.

You can bias a spring unit like this toward one function or another by ….either slightly extending it and keeping it from rebounding by its end mounts and center rod stops….or by slightly compressing it on its center rod.

These types of spring dampers…and the four ways….were augmented and made more adjustable …by adding lever arms and actuating rods. By adjusting length of rod you could make very fine adjustment to the damping pressure.

The difference in the J-shock is that it can use all of the available tricks just mentioned (lever arms, short and long stroke etc.)…but can have digital on the fly adjustability…or even temperature and traction control adjustability via sensors in other parts of the car.

It can also be made to mimic…either the spring (make the J-shock unit mimic fluid damper valving rates while being sued whit ha physical spring)…or the damper (make it mimic spring rates while being used with a physical fluid damper)…or if its large enough it can act like both combined.

Just some thoughts . Ray

[fusername]

didn't realize this wich hunt had ended so well! makes me reconsider my shock plans. Funny enough, those clip on coil overs are exactly what I ahve sitting in a NOS box, gonna toss em on the bus untill I have the time to cutn and turn the beam.

[Steve Arndt]

Do you ever consider cleaning any of the 50 years of grease off your car pile?

[Piledriver]

Do you ever consider cleaning any of the 50 years of grease off your car pile?

No, never crossed my mind

I do hit it pretty hard with the grease gun every ~3K...
(Using Valvoline synthetic moly EP that is rated for CV joints)

That mess and maintenance (and slop in the steering) is about the only reason I'm dabbling with going double wishbone, using a 914 or early 911 lower and fabbing an upper arm mount. The 914 torsions will probably stay.

No room to do that on a 914, but plenty on a T3.
(I'd like to run the lower arms and stuff backwards)

[fusername]

keeps the rust at bay

[KentT]

OK... who's prepared to reverse-engineer a set of these for me to install on Mexican Boge shocks for a '69 BJ/IRS?

I'm ready to buy...

[Piledriver]

It would be cool if someone could cast the aluminum bits, they are essentially universal, then just get the 2" ID springs from Coleman racing or such.

The patents are long expired.

[Soul]

I scored a set of Ford van 4 way shocks on eBay for $30.00. The only problem is that they are stud mount on one end, which would be perfect if I had a ball joint Type 1 front end that these were going on. Now I need to come up with a clamping solution for the top of the springs.

[Piledriver]

Killer score, I ended up spending ~$100.
I can easily visualize an adapter for the rear, as the rear is in double shear, front trickier unless you do some welding.

Sadly you probably won't be able to use the shocks themselves, but AFAICT they are made by Monroe anyway.

[Soul]

I just purchased a new set of Monroe's for the front and Keep you bouncing (KYB's) for the rear. Let's hear your clamping arrangement for the rear. I think that you mentioned a split collar earlier in this thread and I've been looking at those.

I've found some slotted coilover top collars for Monroe shocks that will handle a 2.5" spring for $13.00. I'm leaning heavily in that direction.

I've also thought about about a simpler implementation of the setup below.