I just finished installing front and rear sways and after running into a few hiccups and searching Prime for answers I wish there had been a more concise write up (or maybe I just didn't find it), so here's my stab at it.
Background:
My car is a 1991 and the install was for the Science of Speed adjustable sway bar kit with OEM end links. It's currently lowered with BC Racing coilovers about 1.25" if that makes a difference.
Tools:
-10, 12, and 17mm sockets
-17 mm box wrench
-6mm allen wrench (6mm allen head on a ratchet will make your life a lot easier if you have one)
- ~4" ratchet extension
-breaker bar (optional)
-PB blaster / liquid wrench / penetrating oil (optional)
Overview:
The install process is pretty straight forward and "only" involves removing a few nuts and bolts but like always unexpected things may come up and make life difficult :smile:
I was working from under the car with the front wheels (and later the back) on ramps because I didn't have jack stands, as a result I couldn't take off the wheels for easier access to the end links from the outside. The wheels must be level with one another so they sway bar isn't twisting when being removed (side to side, not front to back). Everything can be done in about an hour with one person if it all goes smoothly, and longer if things are stuck.
Install:
Front:
1. Spray all of end link nuts with PB Blaster first (total of 4) and wait for it to soak in (now's a good time to do the back as well). Mine were stuck on and even after this it was incredibly difficult to get them off. As far as I can tell you won't be able to get an impact gun in there (with the wheels on), a pneumatic wrench would probably fit fine through the a-arms.
2. Unbolt the end links from the a-arms. This can be loosened with a 17mm socket on a breaker bar, once it starts to move you'll need to switch to the 17mm box wrench + 6mm allen wrench (don't forget to use the allen wrench on the end of the bolt otherwise you'll just be spinning it indefinitely)
3. Remove the spare tire and then the bolt that connects the top of the spare tire rack up near the windshield with the 10mm socket (your battery tray won't lower without this removed)
4. Remove the bolts holding the sway bar mount bushings in place with the 12mm socket + extension
5. There are 6 12mm bolts that hold the battery tray in place. Remove the forward 4 and loosen the 2 rear ones so that the tray drops downwards only in the front (this will allow the sway bar to slide out). Be sure not to let the tray drop all the way down otherwise you'll stress the battery cables, I put a jack underneath it so I could lower it slowly and take some weight off the 2 remaining bolts.
6. Remove the sway bar. Getting this thing out reminded me of one of those metal link puzzles where you have to separate the two links that seemingly can't be separated. There's a way you can orient the bar so that it just barely comes out but I don't know how I did it exactly. When you do figure it out take note so you can actually get the new bar back in :biggrin:
7. Now that the bar is out, remember its orientation so you know which way the new one goes in (If I remember correctly the "bump" in the center of the bar goes upward so that it clears the battery tray).
8. People have mentioned that the sway bar hits the radiator hose, I took their word for it and used a jack to bend the hose upwards some. There's a tab welded onto the chassis (seen left of the pipe) that wraps around and creates a protrusion on the pipe that the jack can press against. Note the position of the pipe and slowly bend it upwards (keep in mind that it will flex back down in place once the jack is removed somewhat). I used a BMW X5 jack for this since the NSX one can't reach high enough but you can simply toss some wood blocks under as well. Once the sway bar is installed this area isn't as easily accessible. I'm sure there are other ways you could bend the tab but I chose this one so I wouldn't put pressure on the pipe and risk deforming it.
9. Remove the end links from the sway bar using the same tools as before, consider cleaning the bolt threads and nut so they're easier to reassemble. You can also remove the end links from the swaybar while it's on the car but in my case they were stuck and I couldn't get enough leverage to remove them with the chassis and suspension components in the way. If you decide to go this route leave the bushing/mounts attached so the bar moves less while you listen the nut.
10. Swap the end links from side to side and tighten them up, putting them on now makes them easy to tighten without ratcheting back and forth for 5 minutes but a tad trickier to get in. I was able to use the back 2 holes but not the first (stiffest), there's just no way it'd reach with the OEM end links as far as I could tell.
11. Slide the sway bar back into position. Hope you remembered how it's done!
12. Reattach the end links to the a-arms and tighten
13. Grease the sway bar bushings (optional I suppose?), attach them and fasten the metal brackets over them. I originally assembled everything together and they just ended up getting in the way and I got grease all over my hands, definitely best to wait.
14. Reattach the battery tray (6 bolts), spare tire mount (1 bolt up top), and the spare tire
Rear:
The rear is the same process as the front except you have a lot more room to work. This time though only detach the end links from the sway bar (the other side shares a bolt with your struts). The rear sway bar comes out by rotating it counter clockwise towards the passenger side of the car over the exhaust (assuming you're under the car at this point). Be careful not to stab the CV boots while you're moving the sway bar around.
Misc:
-NSX-R lower chassis brace may hit the sway bar, you'll need spacers to remedy this
-There may be interference with the spare tire holder (not the battery tray underneath it), if so you can either trim it or bend it out of the way
-Dali trophy bar install is more complex, see related threads for that
-If you are hearing noises but aren't sure where from, you can jack up one corner of the car which will cause the sway bar to move and may be able to see whats rubbing then
Background:
My car is a 1991 and the install was for the Science of Speed adjustable sway bar kit with OEM end links. It's currently lowered with BC Racing coilovers about 1.25" if that makes a difference.
Tools:
-10, 12, and 17mm sockets
-17 mm box wrench
-6mm allen wrench (6mm allen head on a ratchet will make your life a lot easier if you have one)
- ~4" ratchet extension
-breaker bar (optional)
-PB blaster / liquid wrench / penetrating oil (optional)
Overview:
The install process is pretty straight forward and "only" involves removing a few nuts and bolts but like always unexpected things may come up and make life difficult :smile:
I was working from under the car with the front wheels (and later the back) on ramps because I didn't have jack stands, as a result I couldn't take off the wheels for easier access to the end links from the outside. The wheels must be level with one another so they sway bar isn't twisting when being removed (side to side, not front to back). Everything can be done in about an hour with one person if it all goes smoothly, and longer if things are stuck.
Install:
Front:
1. Spray all of end link nuts with PB Blaster first (total of 4) and wait for it to soak in (now's a good time to do the back as well). Mine were stuck on and even after this it was incredibly difficult to get them off. As far as I can tell you won't be able to get an impact gun in there (with the wheels on), a pneumatic wrench would probably fit fine through the a-arms.
2. Unbolt the end links from the a-arms. This can be loosened with a 17mm socket on a breaker bar, once it starts to move you'll need to switch to the 17mm box wrench + 6mm allen wrench (don't forget to use the allen wrench on the end of the bolt otherwise you'll just be spinning it indefinitely)
3. Remove the spare tire and then the bolt that connects the top of the spare tire rack up near the windshield with the 10mm socket (your battery tray won't lower without this removed)
4. Remove the bolts holding the sway bar mount bushings in place with the 12mm socket + extension
5. There are 6 12mm bolts that hold the battery tray in place. Remove the forward 4 and loosen the 2 rear ones so that the tray drops downwards only in the front (this will allow the sway bar to slide out). Be sure not to let the tray drop all the way down otherwise you'll stress the battery cables, I put a jack underneath it so I could lower it slowly and take some weight off the 2 remaining bolts.
6. Remove the sway bar. Getting this thing out reminded me of one of those metal link puzzles where you have to separate the two links that seemingly can't be separated. There's a way you can orient the bar so that it just barely comes out but I don't know how I did it exactly. When you do figure it out take note so you can actually get the new bar back in :biggrin:
7. Now that the bar is out, remember its orientation so you know which way the new one goes in (If I remember correctly the "bump" in the center of the bar goes upward so that it clears the battery tray).
8. People have mentioned that the sway bar hits the radiator hose, I took their word for it and used a jack to bend the hose upwards some. There's a tab welded onto the chassis (seen left of the pipe) that wraps around and creates a protrusion on the pipe that the jack can press against. Note the position of the pipe and slowly bend it upwards (keep in mind that it will flex back down in place once the jack is removed somewhat). I used a BMW X5 jack for this since the NSX one can't reach high enough but you can simply toss some wood blocks under as well. Once the sway bar is installed this area isn't as easily accessible. I'm sure there are other ways you could bend the tab but I chose this one so I wouldn't put pressure on the pipe and risk deforming it.
9. Remove the end links from the sway bar using the same tools as before, consider cleaning the bolt threads and nut so they're easier to reassemble. You can also remove the end links from the swaybar while it's on the car but in my case they were stuck and I couldn't get enough leverage to remove them with the chassis and suspension components in the way. If you decide to go this route leave the bushing/mounts attached so the bar moves less while you listen the nut.
10. Swap the end links from side to side and tighten them up, putting them on now makes them easy to tighten without ratcheting back and forth for 5 minutes but a tad trickier to get in. I was able to use the back 2 holes but not the first (stiffest), there's just no way it'd reach with the OEM end links as far as I could tell.
11. Slide the sway bar back into position. Hope you remembered how it's done!
12. Reattach the end links to the a-arms and tighten
13. Grease the sway bar bushings (optional I suppose?), attach them and fasten the metal brackets over them. I originally assembled everything together and they just ended up getting in the way and I got grease all over my hands, definitely best to wait.
14. Reattach the battery tray (6 bolts), spare tire mount (1 bolt up top), and the spare tire
Rear:
The rear is the same process as the front except you have a lot more room to work. This time though only detach the end links from the sway bar (the other side shares a bolt with your struts). The rear sway bar comes out by rotating it counter clockwise towards the passenger side of the car over the exhaust (assuming you're under the car at this point). Be careful not to stab the CV boots while you're moving the sway bar around.
Misc:
-NSX-R lower chassis brace may hit the sway bar, you'll need spacers to remedy this
-There may be interference with the spare tire holder (not the battery tray underneath it), if so you can either trim it or bend it out of the way
-Dali trophy bar install is more complex, see related threads for that
-If you are hearing noises but aren't sure where from, you can jack up one corner of the car which will cause the sway bar to move and may be able to see whats rubbing then
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