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BenArtM80
08-30-2008, 03:40 PM
I lurk a lot, and don't post much except to buy or sell, but I figured I would try my hand at a write-up.

I had been accumulating the pieces for a bottom mount t28 setup for my freshly rebuilt s14 KA and I also wanted to upgrade the suspension. I finally got most of what I needed and over the past two months, I've had my car on jacks in my driveway. The turbo setup isn't that interesting, but my suspension job got a lot bigger than I had planned.

I purchased a set of Stance GR+ coils from another member and installed them on my car (stock brakes and wheels). I was a little disappointed in the fact that I couldn't lower the car as far as I wanted because I already had the camber plates maxed out, but I still had negative camber. I bought some SPC (not SPL) RUCAs for the rear which helped even it out some, but I ended up raising the fronts a little to try to get it close to neutral. Initially I was hoping to just throw some polyurethane collars on with the coilovers, but when I checked out the subframe, most of the bushings were cracked and I had been getting some noises while driving. I decided to go with some poly subframe and diff carrier bushings from ES(for a 300zx subframe since they're similar, part numbers 7.1108 and 7.4102). I also had a spare subframe (thanks Russ) that I could work on in the meantime. Along the way, I learned a good bit of info from here, but also learned a few things the hard way that hopefully you can avoid. So here's my subframe rebuild.

Removal isn't too hard. With the car on jacks/blocks (make sure it's high enough in the rear), first take off your wheels (if you need this explained, go away). Support the weight of the rear end with a jack and remove the driveshaft. http://inlinethumb10.webshots.com/42057/2270506010098236118S600x600Q85.jpg
Next, removed the bolt that holds your strut/coilover to the knuckle (or maybe it's the spindle) like so http://inlinethumb51.webshots.com/42546/2980409550098236118S600x600Q85.jpg
After that, remove the four bolts (two per side) that hold two brackets on the front two subframe studs, here is what the brackets look like
http://inlinethumb36.webshots.com/40931/2622699920098236118S600x600Q85.jpg
and here is where they were bolted to
http://inlinethumb64.webshots.com/43135/2030148110098236118S600x600Q85.jpg
At this point, you need to decide if you are going to remove the brake hardware with the subframe. I chose to remove the rear calipers from the subframe as it seemed easier at the time and I would recommend this if you don't have any brake upgrade planned while the subframe is out.
http://inlinethumb36.webshots.com/38179/2167126250098236118S600x600Q85.jpg
Once the calipers were removed (and rotors set aside), ensure the jack is under the subframe (right under the main part of the diff works fine) and loosen the four nuts that hold the subframe to the car (I know...this bushing doesn't actually look too bad)
http://inlinethumb38.webshots.com/43429/2417588660098236118S600x600Q85.jpg
mine came down pretty easy and you should notice that the subframe will shift a little as the weight is transferred to the jack. DON'T drop your jack all at once. Go slowly for two reasons. First, you don't want to damage the studs because I don't even know if you can replace them. Second, there are still some things attached (e-brake lines, diff vent hose, and ground wire). So lower a little bit until you can get at the aforementioned items easier)
http://inlinethumb31.webshots.com/43614/2302909880098236118S600x600Q85.jpg
http://inlinethumb36.webshots.com/41635/2953853240098236118S600x600Q85.jpg
Slowly lower the jack ensuring that you haven't missed anything and pull the jack back with the subframe on top of it, adjusting as necessary to keep the weight balanced. You might have to remove the mudflaps as well to clear the rear of the car
http://inlinethumb37.webshots.com/14244/2775186800098236118S600x600Q85.jpg
http://inlinethumb61.webshots.com/40764/2916248910098236118S600x600Q85.jpg
Now all that's left to do is remove all the components and replace what you want. I went with the whole package from SPC (RUCA, toe and traction rods). They seem to be quality pieces that are better than the ebay arms, but cost less than the high end stuff. They don't have heim joints, so take that into consideration, but it's not a big deal to me. Removing the hub and axle can be difficult since the bolts will be rusted some. DO NOT pound on the threaded end of the axle with anything other than a rubber mallet (and use caution with that). You will compress the threads and will not be able to re-use it. I learned that one the hard way, but thanks to a fellow member, I got a replacement. I also decided to try out my Eastwood powdercoater for the first time. Here are a few of the coated items
http://inlinethumb49.webshots.com/42352/2036852570098236118S600x600Q85.jpg
I also purchased the ES bushings for the knuckle and arms. You'll have to press the old bushings out, but the ES bushings can be re-installed with a clamp or vise (you'll figure it out). Make sure you use lube, you don't want squeaking (that's what she said). For the subframe, you need to decide which bushings you are going to use before you start hacking away. If you recall from above, I was hoping to go with ES bushings, but the thing is, they don't keep them in stock anymore at their factory, and each order is custom made (or so I'm told). I finally received them a week or two ago (6 weeks after ordering) and they are for sale if anyone wants them (PM please if interested). If you do use ES bushings, ensure that you DO NOT destroy the bushing when you remove it. The best option is to have it pressed out, but alternate methods of burning and scraping can also be effective (search for subframe bushing removal). For poly bushings, the end result of removal should be a metal cup sort of piece that you re-use with the new bushings. Here are Energy Suspension's very own directions in case it helps http://www.energysuspension.com/pdf_instruc/17303.PDF
So it had been a few weeks with no bushings in sight when I finally got fed up and decided to go with solid aluminum ones. If this is your route, feel free to pull out the sawzall and air chisel, just be careful not to cut into the subframe. A little nick here and there won't hurt, but again, be careful not to cut into the subframe. Fortunately, I had a spare to to prepare while I was waiting for parts.....unfortunately, my parts didn't show up as quickly as I hoped. It's also a good idea to paint/powdercoat the subframe before re-installing everything. I just used rattle can truck bed liner since I didn't have a big enough oven to powdercoat it. Anyways, back to the solid aluminum bushings. I got mine from Ebay (deluboz was the seller) and I don't have any driving experience with them yet, but they seem to be decent quality. SPL also makes these. For the diff carrier bushings, SPL is the only one who makes them that I know of and they worked with me and let me just buy the two that install into the subframe. Throw them in the freezer overnight and the following morning, pound them in with a rubber mallet....simple as that. They all went in fairly easily and straight for me. For the subframe bushings, there is a top and bottom, make sure you install them correctly (the top one is flat, the bottom one is recessed to fit the nut when the subframe is re-installed on the car). For the diff bushings, the recessed end should face the rear of the subframe, as installed on the car, again to allow for the nut to thread on to the diff cover studs. Sorry, no pictures of this. After the bushings are installed, re-install the knuckles, hubs, axles, diff, swaybar, and multi-link arms (toe, traction, ruca). This is all pretty easy if you have already taken it apart, so I'm not going to go step-by-step. One note on the multi-link arms. Use your stock arms to tentatively adjust your aftermarket ones (if you so choose). Seems common sense, but you never know. Regardless, your alignment will be jacked up, so make sure you take it to a reputable alignment shop before you go wreck your car. After everything on the subframe is re-assembled, get a buddy to help you put it on your jack the same way it was when you removed it. You can remove everything by yourself, but get a friend to help put the completed subframe back on. Have your friend raise it slowly while you line up the four studs with the four new bushings. If you take your time, you shouldn't have too much trouble. I had mine done in place with the four nuts tightened in less than 30 minutes.....and that was taking my time. However, I was in such a hurry to replace the subframe that I didn't take a picture of everything once it was painted/coated and put back together, so you'll have to settle for an underneath shot from after I had bolted it back up to the car. Hopefully I will have it back on the road by next weekend to actually drive it some, just have to finish up a few things. Sorry for the crappy pic
http://inlinethumb33.webshots.com/5408/2496420770098236118S600x600Q85.jpg

Part two is my solution to some wheel rub on my coilovers. Quick re-cap from above....Stance GR+ coils, too much negative camber, but now I'm mounting some SSR Professor SP1 wheels (18x9.5 +22). With everything bolted up, my rim was rubbing the coilovers in the front. I tried a 5mm spacer, but I could only get 2-3 turns on each lug nut, and I don't feel safe driving around like that. I tossed around the idea of slotting the bracket on the coilover, but was a little hesitant for fear of damaging them. I searched around on here and found some folks that recommended it, so I thought I would give it a shot. At first, I was planning to slot the top hole towards the outside of the bracket, however there isn't much material to work with there, so I ended up slotting the bottom hole towards the inside of the bracket. I didn't really measure anything, I just eye-balled it and used the circular marks from where the bolt had scratched the paint when they were previously installed as my endpoint for the slot. Work carefully, using the bolt as a guide for how much to remove and to ensure your slot is rounded correctly on the end. It probably took close to 30 minutes with a Dremel and a couple grinding bits for each hole, so 2 hours for both coils. When I was done, I test fit with the wheels mounted, and I had just as much, if not more clearance than I did with the spacer. Here are pics after slotting
http://inlinethumb28.webshots.com/43547/2515138360098236118S600x600Q85.jpg
http://inlinethumb31.webshots.com/13662/2509763200098236118S600x600Q85.jpg
Of course, with a slot in there, the possibility exists that the bracket could move around during driving, and I wanted to make sure that everything is as solid as can be. I found some washers that were the same ID as the OD of the bolt. I cut them in half, and subsequently cut/ground them some more to fit in the opposite side of the slot that I had made (the original holes from the factory. I ground off the paint from the coilover bracket to ensure clean welds and welded the piece of the washer in the slot. Now I basically had 'new' bottom holes in the mounting bracket that are more towards the interior than the stock location. I cleaned up all the welds and used some flat black Rustoleum paint to prevent corrosion. Here is the final version before re-installing (note that the coilovers are upside-down in the picture, the upper hole is the one I modified)
http://inlinethumb40.webshots.com/30951/2891587230098236118S600x600Q85.jpg
By moving the bottom holes inward, the top of the front spindle is tilted out, resulting in more + camber and it pushes the wheel away from the coilover. For me, it was a win/win situation......less negative camber, and more room between the coils and wheels (even more than with a small spacer). Plus I don't have to worry about the extra width from the spacer (I already need a pull and a roll on my fenders, or maybe a rub and a tug......something). If you don't have welding/fabricating ability or if you can't picture how this works, don't try customizing your coilovers. However, if you just need a few mm of room and are willing to do a little work, this might help you out. Here is the final pic of the wheels and coilovers installed. Because of the flash, it distorts the size of the rim, but there is actually about 4-5 mm between the wheel and the coilover. http://inlinethumb50.webshots.com/42353/2331103090098236118S600x600Q85.jpg

So, two for one, hopefully you can gain something from this, it took quite a bit of work (not to mention typing). Sorry for the length, but I wanted to be thorough. I'm sure I forgot something here or there, so feel free to ask questions or make suggestions if you know what you are talking about.


Ben:coolugh:

projectRDM
08-30-2008, 03:52 PM
I told you the slotting would work. +1, can't wait to see it with the wheels on.

Nikeboy355
08-30-2008, 06:21 PM
Great write up...
Subframe work is so rewarding...

Let's see some pics with those SSRs...

BenArtM80
08-31-2008, 06:45 AM
Thanks for the props and rep, it will be rewarding once I can drive it again, hopefully this week if all goes well

gotta240
09-01-2008, 10:18 AM
Well done!!!

bigOdom1
09-01-2008, 10:29 AM
congrats shoot me a pm if you need some help.

if im free ill come talk shit while you bust your knuckles.
on another note you should swing in the parking deck one tuesday night a bunch of folks meet up there after nine pm we all chat on aSpeed Racing [ Auburn / Atlanta ] - Powered by vBulletin (http://www.forums.aspeedracing.com)

spngr311
09-01-2008, 12:20 PM
Nice write up -now I'm all pumped up and want to work on my subframe!

JohnnyDrfiter22
09-03-2008, 05:44 AM
hey nice rebuild. I tried finding deluboz on ebay cuz im interested in the solid bushings maybe you can help me out. thanks

BenArtM80
09-11-2008, 04:42 PM
well, after 2 weeks of fighting with an oil leak at the oil sending unit, I was finally able to get an alignment done. For the short drive there and back, the car felt really solid and seemed to handle well, although I couldn't really rag on it much because I think I burnt another valve on the motor. I had the same problem back in the spring (when I was NA), and now it misses really bad at idle and sounds exactly like it did before. I have my old motor that will hopefully be going into it, I've had nothing but trouble with this one. Unfortunately, I'm moving in a week, so I'm going to have to put all that on hold for awhile and again not be able to drive my car. Anyways, here are a couple pics of it's short-lived time on the road. Photography isn't one of my skills

http://inlinethumb22.webshots.com/43797/2118944450098236118S600x600Q85.jpg

http://inlinethumb15.webshots.com/42894/2195575390098236118S600x600Q85.jpg

http://inlinethumb49.webshots.com/42096/2927954840098236118S600x600Q85.jpg