Shocks, Valving, and other confusing items

[articulate]

Do you know what the valving is on your shocks? Or is it top secret?

Have you had shocks tuned to your vehicle requirements? Appropriate to weight and anticipated usage? Or did you simply buy a shock of the correct length and off-the-shelf valving, and called it good? Or did your shocks come with a kit your purchased with springs? Do you know if those shocks are tuned to your vehicle requirements?

For this discussion, it doesn't matter what vehicle you have. I'm curious how you've gone about buying shocks, and if you've been happy.

 

[crawler#976]

I'm using Bilstein 5150's on the trail beater. They are valved on the soft side (170/60). At it's current weight of about 4200 LBS, it's a bit mushy between the soft springs and shocks, but does very well off highway.

For the '98 Taco rear shocks I'm using a stiffer valved Bilstein 5125 (255/70) along with the Deaver 8 leaf springs. They helped control body roll better than the prior shocks did, yet still ride very well off highway. The same shocks are used with the Donahoe/Demello Stage 1 kit on the '05 Taco, and the results are similar.

On both Tacos I don't have a clue as to the valving rates of the SAW's on the 98 or the Donahoes on the '05. Both brands of coilovers work well tho...

Mark

 

[Scott Brady]

All of my shocks are custom valved to my trucks weight. I am also planning to augment compression valving with a hydraulic jounce.

 

[articulate]

I'm using Bilstein 5150's on the trail beater. They are valved on the soft side (170/60). ...

For the '98 Taco rear shocks I'm using a stiffer valved Bilstein 5125 (255/70) along with the Deaver 8 leaf springs. They helped control body roll better than the prior shocks did, yet still ride very well off highway.

Mark

Okay, gotcha. BTW, I forgot to mention that I'm looking at rear suspension in this instance.

That's cool that you have experience with those two valve settings. I am considering the 5150 with a 255/70 setting, but started to wonder about specifically tuned shocks for my application. All loaded up she's at over 5700 lbs (Nissan Frontier).

It's also cool that you know what the setting is. Did you consider specifically tuned shocks as well? Think there is substantial improvement to be gained over what you have or are you plenty satisfied?

thanks,
Mark

 

[articulate]

All of my shocks are custom valved to my trucks weight. I am also planning to augment compression valving with a hydraulic jounce.

Sorry. Missed this.

Okay, custom valved. I presume you're happy with that? But do you have any idea what the valving is? That's the part that tends to be top secret. I'm trying to learn all I can.

 

[crawler#976]

Mark,

After helping Mr. BajaTaco install/fabricate mounts for his custom valved 2.5" remote res SAW's, and hearing from him on how much better it did vs. stock, I'd bet you'd be MUCH happier with a similar setup. I'd also guess your vehicle weights are similar. I know he went thru stock shocks on a regular basis due to heat killing stock shocks.

Initial cost is higher, but the Bilstein 7100 are rebuildable and tuneable.

http://www.bilstein.com/7100_Rebuild.pdf

 

[Desertdude]

I actually in the process of switching to the 7100's. They have been in the garage for over a year now on the shelf - I will have to custom make new mounts to go from stud to eye mount on the upper mounting point and a new redesign for the lower mount to properly fit better.

I spoke with Shane at Bilstein before I bought the shocks and talked about the type of driving, vehicle weight, compression length and rebounding. He recommended, based on our conversation, a valving of 400/100 -- this will be my starting point and I will work to fine tune the shocks if I need to.
Requires a special valve tool and nitrogen.

There are a few of my vehicle com-padres who have just recently blazed the trail on this shock mounting, reports are slowly coming in.

 

[ntsqd]

255/70 is the valve stack that Bils sells for leaf sprung applications. I think that they arrived there after a lot of testing over many years.
That's not to say that you can't do better with any specific situation, but that is what they found to work the best for most situations.
The 170/60 valve stack was originally their baseline stack for multi-damper per tire applications, but it seems that they work pretty good in single damper per tire crawling uses.

Just in case this isn't common knowledge, the damping numbers used by Bils are not the same as those used by anyone else. Each mfg has their own way of rating valve stacks. I believe King only refers to the shim thickness (they only vary shim thickness in their stacks, Bils & other vary both thickness & diameter) where the Bils number is the force in Newtons required to achieve some specific damper shaft velocity. Since those mfg's with damper dyno's use different shaft speeds and different units of Force for their standard each will have a different set of numbers.
There is NO interchange that I know of.

Once you vary from a known shim stack you really have no idea what the damping is unless you have them dyno'd and duplicate that particular mfg's shaft speed. The method King uses eliminates this point of confusion at the expense of not providing a number that Engineer's etc. can work from. That this really matters I doubt. Those to whom it would matter the most either have or have access to a damper dyno & they generate their own numbers.

BTW, 400/100 is the outer limit of what a 14mm shaft can live with. You're well into the Buckling zone if you have any 'wahoo' incidents.

 

[DaveInDenver]

While I like the idea of custom valving my shocks, I wouldn't know the first place to start. When I want my bike shocks tuned, I send them to PUSH Industries up in Loveland. But that's Fox Racing Shox and that's all. I just bought KYB Gas Adjust shocks that fit on my truck and have been spectacularly unimpressed with the ride of my truck. The ARB demo we got spoke to this. While not customizable, Old Man Emu apparently tunes their shocks to the application. So you can pick one of the options for your truck and it is basically valved specifically for the spring (OME of course), weight and payload. I was going to use OME shocks next time and see how that works out.

 

[devinsixtyseven]

Do you know what the valving is on your shocks? Or is it top secret?

No, and no. I just haven't bothered to ask but will probably try to duplicate it when I go SFA.

Have you had shocks tuned to your vehicle requirements? Appropriate to weight and anticipated usage?

They used OTS parts from SAW, nothing crazy, just stuff you can get from Kartek or wherever, and spent a good year or so playing with the valving, nitrogen charge and spring rate, then the shocks were made available to the public, if you knew who to ask and what to ask for. They weren't even a straight bolt-in application for the truck, it took an adapter plate, limit straps, etc...

Do you know if those shocks are tuned to your vehicle requirements?

Yes, they are. The testing was all done on standard and long travel control arms on prerunners. The difference is I probably have another 1K# on them, fully loaded, which isn't often. They don't seem to have a problem, and unloaded they are a helluva ride...just beautiful.

For this discussion, it doesn't matter what vehicle you have. I'm curious how you've gone about buying shocks, and if you've been happy.

It's all about the valving, sorry I don't know more about it. Some of the desert guys with Tundras have even gone to the lengths of attaching a pod camera to the door, to track front wheel movement so they can make changes later to valving, pressure and spring rate.

-Sean

 

[articulate]

Mark,

After helping Mr. BajaTaco install/fabricate mounts for his custom valved 2.5" remote res SAW's . . .

Total droooooool. Beautiful set up he has. His suspension is partly why I ask about custom valving. But then I helped my brother, Greg, install the Donohoe/Deaver with the Bil 5100 on his '07 Taco and noticed that the truck just felt great as we motored through the neighborhood clobbering curbs and avoiding small children. :rally_guys:
Being utterly uneducated about suspension characteristics and shock technology, I still wonder, "Am I going to notice a marked improvement with custom valved shocks?" I might be plenty happy with getting close, and then down the road as I learn more about the tech I can change.

So, I like your suggestion on the 7100 Bils: reasonable cost compared to the SAW, Radflo, etc. and also rebuildable and tunable. And they'll fit in the stock location on the Frontier.

I actually in the process of switching to the 7100's....
I spoke with Shane at Bilstein before I bought the shocks and talked about the type of driving, vehicle weight, compression length and rebounding. He recommended, based on our conversation, a valving of 400/100 -- this will be my starting point and I will work to fine tune the shocks if I need to.

There are a few of my vehicle com-padres who have just recently blazed the trail on this shock mounting, reports are slowly coming in.

Cooooooool.
Fine tuning is a process of trial and error, right? Very un-fun. Keep us updated, though. Is this for your Tacoma or the LC?

255/70 is the valve stack that Bils sells for leaf sprung applications. I think that they arrived there after a lot of testing over many years.
That's not to say that you can't do better with any specific situation, but that is what they found to work the best for most situations........

Okay, all kinds of interesting info in your entire post, thank you.

While I like the idea of custom valving my shocks, I wouldn't know the first place to start. . . I was going to use OME shocks next time and see how that works out.

Ahhhh, yes. Good example of OME. I've been happy with those in the past, but, again, because I don't know any better I wouldn't know where to begin to improve on those.

No doubt that watching some Baja racing footage really helps to see how a sweet suspension operates ... uh, but I'm not a racer.






Sean: You're talking about front suspension (mostly) and I probably didn't make it clear that I'm thinking about the rear suspension. Are you referencing some kind of coilover? For a ______ ?







Current Conclusion:
We drive unloaded during the week and then load up with 600+ pounds of gear for a trip and want to handle rough roads well. I suspect that the valving in the rear shocks on a truck that pulls this kind of double-duty is going to have to accept a certain level of give-and-take and the suspension just won't be perfectly ideal for both driving circumstances. But handling a load is a greater priority to me.

Stay "tuned" for my solution. Something like that 7100 is probably a decent choice that allows me (or some monkey I pay) to dial it in - good call.

 

[SOAZ]

I think the world of valving. It is absolutely amazing what it can do for your ride. In fact, my old tacoma with the donahoes properly valved actually, YES THIS IS TRUE, was better and faster over the same terrain than when I put on total chaos long travel, but with generically valved shocks and incorrect spring rates. It was horrible. I got it sorted, but it always bugged me that there was so much more potential if I only had the time patience tools and expertise that Kreg or some had.
Spring rate and valving, spring rate and valving. Its what its all about!
Look at the VW touregs in the baja 500 this year. They have LESS than half the suspension travel of the american class 1's and trophy trucks and were finishing right beside them.
That being said, I've never seen such a tedious thing. While at Donahoe we would install, jump hit bumps etc, uninstall change valving by one itty bitty shim then put the shock back together and re-install it several times a day for weeks until Kreg and Dylan were happy with the valving for the tacoma shocks. They know more than most and it tooks tens of adjustments. Anyone trying to do this at home with their own shocks will usually end up in a world of hate.
We did it will all of the best tools, extra shock oil and a limitless choice of shims and it took forever!:Mechanic:

 

[Desertdude]

Cooooooool.
Fine tuning is a process of trial and error, right? Very un-fun. Keep us updated, though. Is this for your Tacoma or the LC?

for the 80...


The Tacoma has Donahoe/Deaver/Bilsteins - I could not be happier with the set up.

 

[ntsqd]

snippage.........

Okay, all kinds of interesting info in your entire post, thank you.

You are most welcome. I was in your shoes about late 2000 - early 2001. My grandad instilled in me the social obligation to help those I can as a way of paying back those who helped me.

No doubt that watching some Baja racing footage really helps to see how a sweet suspension operates ... uh, but I'm not a racer.

Uh-huh, that's what we all say........
[/sarcasm]

Current Conclusion:
We drive unloaded during the week and then load up with 600+ pounds of gear for a trip and want to handle rough roads well. I suspect that the valving in the rear shocks on a truck that pulls this kind of double-duty is going to have to accept a certain level of give-and-take and the suspension just won't be perfectly ideal for both driving circumstances. But handling a load is a greater priority to me.

Stay "tuned" for my solution. Something like that 7100 is probably a decent choice that allows me (or some monkey I pay) to dial it in - good call.

Keep in mind that the dampers are all about controlling the springs, not the body. The distinction may seem esoteric, but it isn't. No doubt that a heavier "body" makes the shock work harder, but then so too is the spring working harder.
Ever wonder why the truck just plows over speed bump when loaded, but bucks like horse with a burr in it's blanket when going over a speed bump unloaded?
This isn't due to the suspension's compression, it's due to the rebound. This is true of most every bump. It's not the initial 'hit' that jars you, it's the rebound of the spring throwing the mass of the vehicle up that you feel. That one took me quite a while to accept.

My point is that while the body mass has an influence, the valving for a given spring rate is pretty much the same whether that spring is on a Samurai or a Super Duty. Surprisingly, a bigger factor in damping rate is the unsprung mass more than the sprung mass. If you significantly change the spring rate, then you can expect to need a similar large change in the valving.

As an example I have 4 Fox 2.0 remote res dampers off the rear of a Yota pre-rnnr/chase truck used by one of the LocosMocos until it was retired & parted out. I plan to put them on the front of my '91 Suburban. In talking to Mirage Racing about valve stacks their suggestion was that the stacks should already be close and that I should try them as-is first. I have yet to fab those hoops so I do not yet know how close the valving is, but I'm expecting that their prediction will be pretty good.

 

[devinsixtyseven]

Yeah Mark I was talking about the front. They are thoroughly dialed, through the same painful procedure Tim was describing. Since your truck is similar weight, the spring and valving on the front of my truck would probably work pretty well on your late model Frontier...675# springs, hit me with a PM if you ever want the valving specs and I'll try to dig them up.

Setting up the rear should be much easier, since it's pretty simple to pull the shocks on a leaf spring setup. I wouldn't mind digging in...it'd be a helluva lot easier than pulling apart the front! All a guy would need is the stock shocks to reinstall & drive while rebuilding the good 'uns.

A while back we were talking about weight distribution. It just occurred to me that my truck is about 500# heavier in front (53%F, 47%R), loaded for a long trip...and the rear springs are heavier duty than stock...and your truck is almost pound for pound and inch for inch the same as mine...so here's what I'm getting at:

It's not difficult to weigh your front and rear axles (sprung + unsprung). If your loaded GVW puts your truck at about 50/50 weight distribution without putting much additional weight on the front axle, then you could spec springs to take that weight in the rear, and then use the same valving in the rear as in the front, if you like what's up there already.

Does that seem reasonable? It would probably be easier to use the same manufacturer front and rear, based on whichever you know is tuned properly, then mess with it.

I wasn't aware that shocks were spec'd to springs, not weight, but it's good to know and makes sense...since springs are spec'd to weight. I think I'll try to match the valving in the rear to what's in the front...

I have 7100s with remotes in the rear. They're nice and control the truck MUCH better than the stock shocks ever did.

-Sean