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Discussion Starter #1
Global west makes a bolt in front coil over kit using their tubular lower control arms. Speedtech makes a bolt in coil over kit for the rear.

Wondering what results any of you have had with these sorts of bolt in coil over kits strictly performance/ride quality speaking? The ability dial in ride height seems really nice to me, but my experience with retrofit coil over setups in the past (mainly QA1) is the handling and ride quality left something to be desired versus a well matched coil spring and shock setup. that may have just been because QA1 setups were geared mainly towards drag racing, and I haven't tried anything using these new Viking coil overs that are used in so many kits these days.

So who's using them?! Am I going to be downgrading in performance and ride quality vs my Koni single adjustables and PPM auto x springs?
 

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I've got the full SpeedTech/Viking double adjustable setup in my wagon both front and rear. Have not driven it yet (targeting this spring) but will update here when I do. I'm hoping that with both rebound and compression damping adjustments along with preload/ride height adjustments I can get it to be everything I want.

I opted for the weld in version for the front with the "Chicane" upper brackets, but they (ViKing) do make an OEM replacement version with the stud/rubber bushing mount just like a regular shock absorber. Not sure if SpeedTech sells this option or if you need to go directly to ViKing. I'd also consider reinforcing the upper shock mount as it won't be too happy trying to support the weight of the car. Looks like the global west kit must use a conical spring that mounts in the factory upper frame location and tapers down to sit on the adjust nuts on the damper? The Chicane kit is not difficult to install and you remove very little material from the frame (basically just the "jack-o-lantern" teeth from the upper spring perch) so I'd recommend that. Springs from ViKing are relatively cheap ($50/each) so if you want a different spring rate it's not a huge investment to change it. Does not look like there is any choices with the Global West kit?

I can say that at full "open" on both the compression and rebound they are relatively easy to move by hand and will fall as fast as you can lower a jack with the spindle/hub bolted on the control arms (no spring installed). That is encouraging that they'll be soft enough. If you close the valves down they're really stiff to move by hand (can't really move them...).

The rears don't exactly bolt in to a Roadmaster wagon...they'll work, but you have to do some clearancing of the frame and tilt the shocks a bit so they line up with the bolt on adapters. You do get 3" of ride height adjustment with the lower bracket by flipping it over, plus what you would get with the coil over adjustment so lots of adjustability there. I'm guessing there are some frame differences in a wagon vs sedan, so you shouldn't have any troubles there.

Whatever you decide to do, make sure that you run everything through the full range of motion (without springs) before you actually put it on the road. I've run into a handfull of issues that I wouldn't have thought of before hand. If this is your daily driver, make sure you have a backup plan in case things go a bit off track in the middle of the install.
 

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Discussion Starter #3
I've got the full SpeedTech/Viking double adjustable setup in my wagon both front and rear. Have not driven it yet (targeting this spring) but will update here when I do. I'm hoping that with both rebound and compression damping adjustments along with preload/ride height adjustments I can get it to be everything I want.

I opted for the weld in version for the front with the "Chicane" upper brackets, but they (ViKing) do make an OEM replacement version with the stud/rubber bushing mount just like a regular shock absorber. Not sure if SpeedTech sells this option or if you need to go directly to ViKing. I'd also consider reinforcing the upper shock mount as it won't be too happy trying to support the weight of the car. Looks like the global west kit must use a conical spring that mounts in the factory upper frame location and tapers down to sit on the adjust nuts on the damper? The Chicane kit is not difficult to install and you remove very little material from the frame (basically just the "jack-o-lantern" teeth from the upper spring perch) so I'd recommend that. Springs from ViKing are relatively cheap ($50/each) so if you want a different spring rate it's not a huge investment to change it. Does not look like there is any choices with the Global West kit?

I can say that at full "open" on both the compression and rebound they are relatively easy to move by hand and will fall as fast as you can lower a jack with the spindle/hub bolted on the control arms (no spring installed). That is encouraging that they'll be soft enough. If you close the valves down they're really stiff to move by hand (can't really move them...).

The rears don't exactly bolt in to a Roadmaster wagon...they'll work, but you have to do some clearancing of the frame and tilt the shocks a bit so they line up with the bolt on adapters. You do get 3" of ride height adjustment with the lower bracket by flipping it over, plus what you would get with the coil over adjustment so lots of adjustability there. I'm guessing there are some frame differences in a wagon vs sedan, so you shouldn't have any troubles there.

Whatever you decide to do, make sure that you run everything through the full range of motion (without springs) before you actually put it on the road. I've run into a handfull of issues that I wouldn't have thought of before hand. If this is your daily driver, make sure you have a backup plan in case things go a bit off track in the middle of the install.
Thanks for that awesome writeup!

As far as the shock mount, that's exactly what I was worried about with the chicane kit. I didn't like the idea of applying the sprung weight of the car to someplace other than where it was designed to be supported by. I've seen this backfire first hand in ways I never would have expected on kits that converted torsion bar front ends to coil spring setups on older mopars. With the new way the sprung weight was being applied through the K member, it put all the weight/force of the car on the K member mounts and would actually bend the chassis of the car up. Because of this, I just get worried about the unintended consequences of completely altering the way the force of the front suspension is applied through the chassis. I really liked the global west kit because the only change in where force is being applied to is in the lower A arm, which i'm not too worried about being made out of tube steel.

As you mentioned, reinforcing the spring pockets would be a must if I went that route, but i'm trying to avoid any more welding on the car as I already painted my whole chassis, fogged the inside of the rails with chassis paint etc... If I decide to cut and weld on it again, it opens up a can of worms for me because then I'm going to want to setup a watts link for the rear while i'm destroying my beautiful paint job LOL
 

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Discussion Starter #4
One of the problems I have had with researching these coil over setups is it seems like most of the guys who are running one brand or another are doing them strictly for looks in the ability to adjust ride height on slammed cars with big wheels. I haven't come across anyone performance oriented who autocrosses, road races or otherwise drives their car hard who is running a coil over setup yet, which is unfortunate.

I mean in theory the only difference should be travel, as coil spring setups usually allow for more travel. Other than that, with the adjustability, you SHOULD be able to optimize spring rates and rebound/compression rates pretty easily and fine tune them to your particular car/sway bar setup better than any off the shelf shocks and spring package. In the pre viking days I've heard many people over the years say they weren't happy with QA1 conversion setups on street cars that were geared more towards corner carving. I have installed them and used them on drag cars with great results though. I wonder how the Vikings do as they seemed to be hailed by all to be a superior coil over for handling. Looking forward to hearing your results!
 

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I'm definitely NOT going for the slammed look - I want modern handling in an older car with the ability to adjust ride height easily without risking life & limb putting standard coil springs in. No plans to road race or auto cross or anything, but also don't slow down for curves much either :) and enjoy a nice curvy back road just for fun.

Understood about the painted frame and not wanting to weld on it. Regarding the loading of the frame with the Chicane kit - it's right in line with the original spring pockets and well distributed across a pretty wide (3"+) area both top and bottom so I'm not expecting any issues with strength of the frame. I might see if I can fill in the triangle shaped area toward the back and connect it to the weld in bracket just to give the upper control arm mount a bit more strength. Easy enough to do while I'm there.

As shown below the upper shock mounting point is about 3/4" too high. I'll be cutting the tack welds, trimming the bracket by ~3/4", lowering the mount down and re-welding it on.

 

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Discussion Starter #7
That does look nice! I'm sure it'll work fine, but I'd be much more comfortable if they designed something that sat over the 'ring' of the spring pocket, around the circumference of it, so that the force was being applied to the exact same area as before.

I don't see that being an issue though. Looking forward to hearing how you like the setup once it's up and running. hurry up! LOL
 

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SSandman - I saw this in the scrap bin in the shop last weekend and thought of your desire to have a more perimeter loading of the frame instead of the bracket shown above. I believe this is off a Dodge or Ford 5500/550 front damper (only) so it only sees the damper forces, not the whole weight of the car. But in concept, I think this is what you were getting at.

Sorry, nothing particularly useful here...but might be an inspiration or idea for someone?

 

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Discussion Starter #9
SSandman - I saw this in the scrap bin in the shop last weekend and thought of your desire to have a more perimeter loading of the frame instead of the bracket shown above. I believe this is off a Dodge or Ford 5500/550 front damper (only) so it only sees the damper forces, not the whole weight of the car. But in concept, I think this is what you were getting at.

Sorry, nothing particularly useful here...but might be an inspiration or idea for someone?

Making something like that work would be ideal way to me!

Just as an update, I ended up going with a Speedtech kit front and rear. I went with the Speedtech bolt in front kit using their upper and lower control arms (upper portion of the spring mounts in the spring pocket distributing the load the same way the factory would). I also went with their bolt in rear kit. There's a much lower spring rate in the rear, so I feel OK about the shock mounts supporting the spring tension of the coil over but if I could start from scratch again with my chassis out I would have definitely reinforced the area of the rear shock tower, probably by tying the two towers together somehow.

The install on both kits went very smoothly, they appear to be very high quality parts.

I also installed their front sway bar, again a very nice piece, and their chassis mounted rear sway bar.

For the rear sway bar, I ended up using some Detroit Speed mounts I had lying around just because A) they were a little beefier and B) they allowed more versatility with how the rod ends would be mounted (it's a single tab instead of a dual tab where the rod end sits between, so I can install the rod end on either side). I also ordered some teflon lined rod ends to replace the speed tech steel to steel ones.

One issue I have had so far with the sway bar is it was very hard to find a good mounting point for them that allowed the end links to be perfectly vertical. I don't know if this really matters, as long as the rod ends have enough angle of travel and don't bind up during the articulation of the sway bar.

the chassis mounted sway bar seems like a great idea, but it's another one of these things where I really feel like I am 'half assing' by not fabricating up some sort of mounting point and reinforcing the area of the chassis where they mount to. Looking at many other kits that are sold though, they all appear to use the same style of mounts and the chassis on all of those cars have the same design/thickness as ours, so I'm assuming it's not really an issue.

Another issue with the chassis mounted sway bar is that it doesn't clear my CIA 3" exhaust's tailpipes. they clear the massive Spintech XL's just fine, but they protrude right into where the tailpipe would hookup and it's protruding right into the area where the band clamp would mount so denting it isn't a possibility. What I may do is weld the tailpipe section to the mufflers so that I can dent it then, but I'll deal with that another time.

There were no instructions for the rear bar and I believe this is because the kit was never designed for the B body, it's just an A body bar I believe that they sell for the B body because it can be made to fit . On most other chassis mounted sway bar kits i've installed there are very specific measurements on where to mount the end link brackets so that the sway bar is centered and the end links have the correct angles. for this setup, I'm just winging it and trying to get the bar as parallel to the ground and the end links as vertical up and down and square to the bar as possible.

Hopefully with some luckI can fire the car up, have it tuned and get it road worthy by fall so I'll post a further review on how it is all working on the road then.
 

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That's a similar setup to what I have - full speedtech front/rear, but I went with the weld in front mounts. What shocks did you end up going with?

For the rears, the shock mounts are very sturdy (arguably more sturdy than the coil spring mount) so either way you go will be fine. I'm going with coil overs set to just below the ride height that I want, then airbags in place of the coil springs with the auto leveling system in place to maintain ride height as load on the suspension changes.

Thinking of something like this for the airbags

or these




 

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Quote "For the rears, the shock mounts are very sturdy (arguably more sturdy than the coil spring mount)" end Quote

Well, guys have cracked, bent up rear uppers in impalas on coil overs.

The lower, while thick, you have that wonderful single shear bending action.
 

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Ok - Looking at it, the shock mount is closer to the cross member and frame intersection so I figured it would be pretty (plenty) strong. I'll have to search for some pictures of said cracked/bent mounting - Maybe the sedan's are different than the wagons in this area?

For the lower mount, the kit's brackets put it in double (triple?) shear and distribute the bending forces over lots of material. Some good pictures of the install here

 

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Discussion Starter #13 (Edited)
The upper shock mount does seem very strong by design, but I mean it really wasn't designed to handle any more load through that bolt hole area than the shock itself which is nothing compared to the spring. The factory springs distribute the load across a much larger area. What would have been really cool is if they designed some sort of billet 1/2" block contoured to the shape of the spring pocket that sandwiched between the top of the coil over and the chassis, distributing the load across a greater area of the spring pocket. It kind of goes back to the sway bar thing in that most of these coil over kits aren't really designed for our cars, they are just universal fit items that happen to fit our cars. I just worry because our cars may be a great deal heavier than the cars the designs were engineered for. I still haven't heard of anyone bending them up with coil overs, actually I haven't found much about coil overs on these cars period. Gerry, do you happen to have any of those sources on hand? Curious to read more about that.

As far as the single shear lower, I hear what Gerry is saying, even with all of the mounting points to the axle the actual mounting of the coil over to the bracket itself would still be a single shear load on the fastener. Only thing I can say to defend this is that this is typically the design of most aftermarket coil over setups and I haven't heard of many issues from guys running street car spring rates aside from guys who failed to run bump stops and bottomed out their rears, bending the brackets or mounting bolt.

Fixuntilbroke, on your speed tech kit did you have an issue with the mounting bolts being slightly too short for comfort? The main bolt holding the coil over to the axle bracket on mine barely gets like one thread out of the nylock without any of the washers supplied installed. Just a little unsettling having the single bolt holding your entire rear suspension up being supported by a bolt barely makes it past the bolt's locking mechanism.
 

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Discussion Starter #14
Also, keep us updated on that air bag setup as that looks really neat. I'm a little worried about my ride height with the coil overs. I haven't sat the car down flat on the ground yet and i'm sure the springs have some settling to do, but just jacking the rear up and putting it on jack stands I have the adjustment nut only a few threads from the bottom and the rear is nowhere as low as i figured it would be with it adjusted so low. I guess I will have to see what happens when the car actually hits the ground, has gas in it, the springs settle etc... I was under the impression these would provide up to a 2" drop from stock height which should give me the same stance I had with my old, weathered hotchkis springs that were probably a little lower than the 1.5" drop they advertised.
 

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Discussion Starter #15
Fix Until Broke, I forgot, in my rambling, to answer your question. I went with the Viking double adjustable at the recommendation of the sales rep.

I want this car to handle great, but my logic for this build (don't know if i'm right) is that for a street car, my best bet is to attempt to reduce bind at all the places where stiffening up suspension parts typically induces it. One issue I have always had on these cars is that they handle great with a stiff set of springs, shocks, big sways, poly bushings, boxed trailing arms but put them on an uneven roadway and the rears hop and skip all over the place and articulate like garbage compared to more advanced solid rear suspension designs.

I'm thinking with the more effective chassis mounted sway bar in the rear, the offset clevis rear upper control arms I welded up for the rear to account for the angle change of the extended LCA's, the mix of poly and Johnny Joint'son the lower trailing arms and Johnny Joints and rubber bushings on the uppers will all help the suspension articulate much more effectively.

The chassis is also a little stiffer now since I boxed it and welded in a some old roll cage tubing between the rear rails as an 'RMS' bar.

still a little worried I should have went with the stiffer ride tech coil overs over the Vikings but the car spends almost all of its time on the street anyway.
 

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I get it that so many of this kits are designed for bolt on people.
I doubt if they were " clean sheet of paper" they would be done the way they are.
Not a great fan of poly shock bushings holding the entire weight of the car.
Also you are never supposed to have threads up against brackets and sleeves.
Doesn't take long for threads to chew into stuff when the weight of the car is on them
Unfortunatly proper grip length hardware , NAS or otherwise, would cost to much.
The least a guy could do is buy the correct shank length and remove the extra thread.
 

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Discussion Starter #17 (Edited)
I get it that so many of this kits are designed for bolt on people.
I doubt if they were " clean sheet of paper" they would be done the way they are.
Not a great fan of poly shock bushings holding the entire weight of the car.
Also you are never supposed to have threads up against brackets and sleeves.
Doesn't take long for threads to chew into stuff when the weight of the car is on them
Unfortunatly proper grip length hardware , NAS or otherwise, would cost to much.
The least a guy could do is buy the correct shank length and remove the extra thread.

Never really thought of the shock bushings, but the spherical bushings on the lower rear shock mount doesn't seem like a great idea. With that said though, I do know of many street cars running similar style coil over setups without issues but the ones I know of are in older muscle cars that are probably a lot lighter than full a weight a B body.

I'm pretty comfortable with the front setup, using the factory spring pocket for the coil spring. The lower half is supported by the T bar/shock bushing but a failure there wouldn't really be catastrophic, just nuisance to have to replace the bushing.

The rear is definitely where most of the design flaws seem to be apparent. The mounting of the upper to the chassis's shock mount, the single shear lower and the fact that it is all being supported by a spherical bushing on the axle end. Only thing that makes me feel a little better about it is there is obviously less weight and less spring tension over the rear than the front, so the whole design is under a bit less stress. If all goes well, I plan on driving the crap out of this car. Full weight (actually heavier than full weight because of all the add ons), lots of HP and I plan on putting a lot of miles on it so we will see how it goes.

I will say I'd probably be very worried about a setup like this on a daily driver just because the spherical shock bushings are exposed and uninsulated. The most likely reason for failure on those (other than maybe from an impact caused by a bottoming out of the rear with no bump stops) is going to be from contaminants wearing it out, and i'm sure that will be sped up a lot if driving on slushy, salty, wet roads.
 

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SSandman - We're pursuing the same goal more/less, modern handling in a "middle aged" car that gets driven on real streets/roads :).

I haven't finally bolted things together yet so don't know about the bolt lengths. Washers are a really good idea so it might be worthwhile to get a couple longer bolts so you can put the washers on. They do as much to keep things from loosening up as the nyloc nuts do in my opinion.

I went with the same Viking Double Adjustable dampers (just longer stroke on the fronts since i used the full coil overs instead of the hybrid springs). I'm hoping to be able to dial them in to the best compromise in ride and handling. What spring rates did you go with front & rear? I've 750 lb/in front and 450 lb/in rear.

I've been posting updates in the "What did you do to your Wagon this week" thread and will post on the airbags when I get that far. For now it's just going to be on the springs until I get some miles on it. I'm not looking to "slam" it or anything, just to maintain ride height as the load changes due to cargo or trailer. It should work (?) and the air compressor won't have to work too hard as the airbags will push 1700 lbf (or 2140 lbf) each at 100 psi so I can't see them needing to ever exceed 35-40 psi unless I'm doing something really dumb :).
 

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Never really thought of the shock bushings, but the spherical bushings on the lower rear shock mount doesn't seem like a great idea. With that said though, I do know of many street cars running similar style coil over setups without issues but the ones I know of are in older muscle cars that are probably a lot lighter than full a weight a B body.

I'm pretty comfortable with the front setup, using the factory spring pocket for the coil spring. The lower half is supported by the T bar/shock bushing but a failure there wouldn't really be catastrophic, just nuisance to have to replace the bushing.

The rear is definitely where most of the design flaws seem to be apparent. The mounting of the upper to the chassis's shock mount, the single shear lower and the fact that it is all being supported by a spherical bushing on the axle end. Only thing that makes me feel a little better about it is there is obviously less weight and less spring tension over the rear than the front, so the whole design is under a bit less stress. If all goes well, I plan on driving the crap out of this car. Full weight (actually heavier than full weight because of all the add ons), lots of HP and I plan on putting a lot of miles on it so we will see how it goes.

I will say I'd probably be very worried about a setup like this on a daily driver just because the spherical shock bushings are exposed and uninsulated. The most likely reason for failure on those (other than maybe from an impact caused by a bottoming out of the rear with no bump stops) is going to be from contaminants wearing it out, and i'm sure that will be sped up a lot if driving on slushy, salty, wet roads.
 
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