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About to completely tear the suspension apart


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measure the ride hieght from the bottom of the rockers to the ground, front and back, just for reference. When you're done you'll be trying to remember how high the car sat. And measure from the top of the wheel arches to the center of the wheel hubs with the car sitting on the ground at normal ride height. This will give you a reference later when you mock up the suspension to decide how much to cut and where to put the new spring perches.

Good luck with those spindle pins!

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I have been accused of over-analysis of a subject, but in this case I'd look hard at the many strings on this issue before you start because the problem of having the threaded tube too high or too low has come up too many times to ignored. There are a lot of things to consider (ride height, spring rate, corner weight, strut insert length, and are other components being added at the same time such as caster adjusters. I'm sure I've missed other issues as well.

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You know... I've been on this site for around a year - and I've read a lot of posts. A whole lot of you (and you know who you are) are FAR too quick to pull out the "do a search" card. I read the FAQ and NOWHERE on the post does it discuss measuring un-modified ride heights or un-modified strut travel or any of the MANY other factors which may be important starting points for a modification like this. mom'sz and blueovalz have done a great job of starting the questions. Strut selection, strut top/camber plate choice, amount of section, differences between 240 and 280 strut tubes, clearances and many other subjects are all important factors when doing this modification and I want to make sure I don't miss something before I start.

 

So without one of the admins or regular posters on this site trying to end the conversation by being an ass by asking me to search - does anybody else have any REAL advice for me before I start the work on my suspension?

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So without one of the admins or regular posters on this site trying to end the conversation by being an ass by asking me to search - does anybody else have any REAL advice for me before I start the work on my suspension?

 

Actually I was trying to be helpful, not an ass. I'll come back later to the thread and read it again before making a decision on what to do with you. I'd not want to be so quick to judge as some people are prone to be.

 

Oh, and another thing, try actually posting more than one sentence explaining what you want to do and why. More pointed questions than just a phrase like...

 

"I'm putting in coilovers and sectioning the struts... Should I measure anything before I start?"

 

...would be good for the readers too. How posts are written with a single questions that begs "SERVE ME!"

 

I'll be back.

 

Davy

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If possible get a helper. (real advice)

 

Are you doing bushings too? If so go ahead and buy new spindle pins, locks and nuts.

 

Save your energy by having the old spindle pins pressed out by a 4x4 shop (they have BIG presses)

 

Get a pint of POR-15 Chassis Coat to coat the parts as they are cleaned and ready for reassembly.

 

Here is a pic of the work I just completed on my car. (not coil overs but suspension rebuild)

 

Go here for more pics.

http://forums.hybridz.org/showthread.php?t=117311

 

100_2856.jpg

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Stuff I'm doing on this overhaul:

- MM coilovers all the way around on sectioned struts.

- new strut tops or camber plates (i'm on the fence, still)

- Adjustable shocks (unknown length so far... depends on my camber plate choice).

- rear disk conversion

- front 4x4 disk upgrade

- Stainless brake lines

- ST swaybars front and rear

- new balljoints, tie rods, steering rack boots, front & rear wheel bearings/seals, spindle pins, and hardware.

- Rebuilt diff w/ 3.9 gears, seals, and new powerbrute from the recent group buy

- Ron Tyler Front Diff Mount

- New rear diff mount

- full energy suspension bushing kit install

- "ball and socket" compression rod upgrade

- ditching the 14" "steelies" and putting on Rota Grid 16x8's w/ 245/45 Bridgestone RE70 rubber all the way around

- a general cleanup under the car - de-rust, clean, & paint everything I can.

- Z31 or 280zxt CV's in the rear

- After reading all of the recent posts about the Z32 trans - I'm pondering installing one of those, too.

 

(it may seem like a big list, but I just completed re-finishing the popcorn ceilings in my house flat - and removed wallpaper/repainted almost all of the interior walls... took all winter. The wife owes me some time to work on the Z).

 

justinolson: I'm not 100% sure on camber plates yet. I've read all bout how they are so loud. I'll mainly be using the car for street driving - so I may just go with new 240 tops... or maybe just camber plates in the front. Because the front strut tops are different sizes than the rears in a stock 280 - and the strut travel from different struts (VW, miata, etc) aren't well documented - I'm just a tad worried about having a car where the ass end is dragging too much when I get it all assembled and back on the ground - or the problem that blueovalz has referred to about not having the spring perch in the correct place

 

dsommer: The underside of your car looks awesome! There are varying opinions about the best method to remove undercoating - what method did you use? Your steering rack really caught my eye... what'd you do to clean it up? I've heard about POR... is the chassis coat you refer to applied with a brush or spray can?

 

davyz: Sorry if I pissed you off, but your comment "Just takes a search and voila" really struck me tonight. I see it all too often on this forum.

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davyz: Sorry if I pissed you off, but your comment "Just takes a search and voila" really struck me tonight. I see it all too often on this forum.

 

OK, I can accept that. I was trying to provide a link to information that I thought would be useful, but it apparently didn't have what you were looking for. Your post above with all the info is what you should provide upfront (or something similar). Often, a super-short post comes off as being short sighted and asking for all the info, just so we understand each other.

 

Davy

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I'm going to tell you one thing - call an admin an ass in public, and you will not be welcome here. It's a private party and calling one of the hosts an ass, even if you think they are being one, is a no-no.

 

Anyone that doesn't understand this concept is not welcome here. PERIOD.

 

Read the rules, especially #12 and the paragraph below #15.

http://forums.hybridz.org/announcement.php?f=58&a=2

 

How in the hell was Davy supposed to know that you searched, didn't find that info you needed? One simple sentence about a complex topic means you either didn't search or were too lazy to write out what you knew about the problem you were tackling and where your holes in understanding were.

 

It's ok - We all make lapses in judgement. Can we start this thread over? Sounds like the FAQ could use some work if there are questions like this still rolling around...

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Sounds like you have your work cut out for you. If I may suggest on your brake upgrade if you going through all this work you should consider the AZ-Zcar brake conversion. Dollar for dollar it is the best money I’ve spent on an upgrade so far. I’ve got 4pt 3” harnesses in my hybrid car and when you stomp those brakes… well you’re happy to be strapped in securely by the harness or you’d be kissing the windshield!

Under coating removal; I would recommend the dry ice approach and a needle scaler. I did not remove undercoating on the car pictured above but did on my hybrid car. Heat works too but in all actuality I wouldn’t get too carried away with removing the undercoating unless you’re trying to repair rust.

POR-15; do a web search, if you’re repairing any rust you’ll want some of this product. The chassis coat I mention is not a rust inhibitor just a tough coating and it is brushed on with a foam brush in light coats. The steering rack was degreased and then coated with POR-15 metal mask, as were the tie rod ends and brake calipers. It gives them an original raw metal look, neat stuff.

I soak everything with oven cleaner to get the initial gunk off then scrub with a stiff bristled brush and warm water, then follow up with SuperClean or Orange blast then a final nook and cranny cleaning with lacquer thinner to remove any remaining oils then coat with POR-15 products. Thoroughly cleaning your parts will yield you the best finish, be anal about the cleanliness of your parts and take your time. You only want to do the job once.

Again reconsider the brakes even if you only go front brakes for now, they’re worth it.

Good luck and keep us posted.

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Hopefully the below can be added to JohnC's wonderfull FAQ. It does not provide specific dimensions, but hopefully will provide the reader a conceptual idea of what all is involved with sectioning struts. If done correctly, is not something you do by measuring with a mic, marking with chauk, and cutting with an ax. It takes some preparation, time, and consideration of a lot of variables before it can be done right.

 

 

Deciding on the strut length (where the top of the strut housing, or the gland nut location) as well as the placement of the threaded tube can only be successfully determined after you know where you want your ride height to be in relationship to where it was prior to the sectioning. For example, if your suspension was set up at a 7” ride height, and the current struts were positioned exactly half-way in their travel window when the car is at rest, you have a reference point to work from in deciding how much to section and where to place the threaded sleeve.

Let’s suppose you wish to lower the car to a new ride height of 5”, and you wish to use the same exact springs previously used on the car. To do this correctly you’ve got to reduce the height (top of, or the position of the gland nut) of the strut tube by the same amount that you’ve lowered the car (2”). Doing this allows the suspension to once again sit at the midpoint of the strut’s travel window. The only way to do this though is with a shorter strut insert because the OEM insert will be too long to fit into the shortened tube. So what you need to know now is “how long is the body of the new shorter strut insert?” If it is at least 2” shorter than the OEM insert, you’re in luck because you can use a spacer to make up the difference at the bottom of the tube. If the new insert body is less than 2” shorter than the OEM insert body, than you must increase the strut tube length to at least match the new strut insert’s body length. This may mean that you cannot cut the full 2” off the tube, and must instead settle with a longer than desired tube (strut length), but one that will still work within the parameters of the suspension travel.

All of the above is only a starting point though. What if the new strut insert has a shorter stroke than the OEM strut had. If the OEM strut had an 8” stroke (just for the sake of this explanation) and the new insert has a 6” stroke, this means that the center of the travel window must be moved up 1” (1/2 the difference between the two strokes). This means that instead of cutting 2” off my strut tube in preparation for lowering the car, you only need to cut 1” off the strut tube, because now you must raise the strut up 1” to compensate for the shorter stroke of the new insert. So now you’ve added another factor to consider before you cut.

One note I would like to add is that it is always better to error on the side of a too long a strut tube. If you cut the strut tube even .200” too short in relationship to the new insert’s body length, you will not have enough thread engagement in the gland nut to secure the insert. In fact, I will go so far as to say even .100” too short can present a problem. With that said, .100” too long will allow the use of a washer or shim to tighten the new insert with proper gland nut engagement. You can always add a shim, but to lengthen a too short a strut tube will take a lot more work.

Guess what, you’re not finished yet. If you install camber plates, or any part that changes the strut rod mounting point’s relationship with the top of the strut tower, then you’ll need to find out what this change is. Will the installation of camber plates allow the strut to sit higher in the tower, or will it push it down lower in the tower? This change will impact where the car sits in relationship to the strut’s stroke window (the desired midpoint of strut movement). A camber plate with no rubber spacer will allow the strut rod to be over-extended at the new ride height if this factor is not considered. Thus in this situation, you’d need to lengthen the strut tube additionally for this situation. How long are your bump stops? Will you use bump stops? Will the upper assembly reduce the available stroke on the new insert, and if so, by how much? All of this needs to be considered because it will dictate where the gland nut is positioned (the length of the strut tube)

 

Threaded Tube Placement

 

Now let’s look at the location of the threaded tube. Nearly 100% of all coil-over conversions involve a change in springs. Your planned ride height change of 2” must take into consideration the spring rate change as well. For example, lets assume the reference ride height (original pre-work ride height) used 100 lb/in springs (again, a value used only for this discussion) on the struts, and you wish to use 150 lb/in springs with the coil-over set-up. This means that the springs will not compress as much as the OEM springs did. At rest, if your corner weight (un-sprung weight) is 600 lbs, then the new spring will only compress 4” as compared to the OEM spring which compressed 6”. If these two springs were the same length (OEM and new), this means the bottom of the new spring must be raised 2” (again, ½ the difference between the two rates) to keep the same ride height. But rarely are these springs the same length, so now the spring length (more specifically, the spring compressed length) then becomes a factor as well. I only mention all of the above to cause you to think about all that goes into this project. In simple terms, if you know the spring rate, and you know the corner un-sprung weight (not total car corner weight), the you can determine the length of the new compressed spring. Then take this “compressed length” value and measure down from the upper spring perch, mark the strut tube at this length (this is with the suspension assembled and installed on the car, and the car sitting at you intended ride height), and then use this location as a good estimate on where the center (midpoint) of the threaded tube should be (actually, this is where the spring perch would be located midway on the threaded tube). Then once you know where the threaded tube should be positioned, the location of where you wish to weld the tube seat is a no-brainer.

Lastly, you need to consider what the use of the car will be. If the car is to be used on the street, but occasionally used on the track, then you may wish to lower the threaded tube so that you can raise the car a small amount for the street, and the lower is a good bit for the track. Regardless, take into consideration whether the car will be occasionally raised or lowered depending upon future use, and then place the threaded tube accordingly. Usually, if the threaded tube is place correctly, and the lower spring perch is used midway up the tube, you should have plenty of room to move the perch for varying ride heights (provide your threaded tube is of sufficient length).

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I'm amazed at how some people get offended when they are asked to help themselves to the information that is abundantly available. I'm further negatively moved that people find it rude that those of us who provide the information, and its ability to be accessed by this very website, and brand us as Asses...

 

TRWEBB, Consider it a gift that you haven't been banned by one of the admins in this thread. Also consider your actions before posting in the future. You are now in the unfortunate position of being a topic of discussion in the admin forum... :2thumbs:

 

Ass, indeed... :roll:

 

Mikelly

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  • 5 months later...
Stuff I'm doing on this overhaul:

- MM coilovers all the way around on sectioned struts.

- new strut tops or camber plates (i'm on the fence, still)

- Adjustable shocks (unknown length so far... depends on my camber plate choice).

- rear disk conversion

- front 4x4 disk upgrade

- Stainless brake lines

- ST swaybars front and rear

- new balljoints, tie rods, steering rack boots, front & rear wheel bearings/seals, spindle pins, and hardware.

- Rebuilt diff w/ 3.9 gears, seals, and new powerbrute from the recent group buy

- Ron Tyler Front Diff Mount

- New rear diff mount

- full energy suspension bushing kit install

- "ball and socket" compression rod upgrade

- ditching the 14" "steelies" and putting on Rota Grid 16x8's w/ 245/45 Bridgestone RE70 rubber all the way around

- a general cleanup under the car - de-rust, clean, & paint everything I can.

- Z31 or 280zxt CV's in the rear

- After reading all of the recent posts about the Z32 trans - I'm pondering installing one of those, too.

 

(it may seem like a big list, but I just completed re-finishing the popcorn ceilings in my house flat - and removed wallpaper/repainted almost all of the interior walls... took all winter. The wife owes me some time to work on the Z).

 

justinolson: I'm not 100% sure on camber plates yet. I've read all bout how they are so loud. I'll mainly be using the car for street driving - so I may just go with new 240 tops... or maybe just camber plates in the front. Because the front strut tops are different sizes than the rears in a stock 280 - and the strut travel from different struts (VW, miata, etc) aren't well documented - I'm just a tad worried about having a car where the ass end is dragging too much when I get it all assembled and back on the ground - or the problem that blueovalz has referred to about not having the spring perch in the correct place

 

dsommer: The underside of your car looks awesome! There are varying opinions about the best method to remove undercoating - what method did you use? Your steering rack really caught my eye... what'd you do to clean it up? I've heard about POR... is the chassis coat you refer to applied with a brush or spray can?

 

davyz: Sorry if I pissed you off, but your comment "Just takes a search and voila" really struck me tonight. I see it all too often on this forum.

 

I know this is an old thread, but anyone seeing this and considering doing all of that should consider reinforcing the front swaybar mounts as they can crack under the excessive loads a large swaybar will put on it.

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