So Ive been really tired of all the clunking, creaking, squeaking etc coming from my suspension -- especially since none of its very old. Today, I took care of the rear.
Heres my setup:
MM LCAs (less than 2k miles)
New factory UCAs
Bilstein HDs
Steeda Springs
Stock sway bar
No isolators
While finishing up my fender roll last week, I peeked under at the LCAs to see how they were doing. Last year ish, MM sent me new LCAs because the urethane front bushing was annihilated for some reason with less than 5k miles on them. Since installing those, my car has seen less than 2k miles. Its a street car with just bolt ons. I can clearly see that the bushing has been allowing the LCA to move forward and back quite a bit. The debris and grease inside the torque boxes is pushed clean around the bushing, 1/4+ inch in each direction.
Now, this is the type of significant deflection I saw last time when I found that the bushings were split inside. So I tore apart the rear suspension, popped the bushings out and surprisingly, they were completely intact. Either way, I'm unhappy with what I see and have been experiencing, so its time to look into some different arms...
A quick web search shows me that replacements with spherical joints at both ends are gonna run me a lot of money. And... Im not 100% sure theyre what I want.
Fortunately, Ive had some special bushings clunking around in my toolbox for some time. And, I've got the tubing lying around to tackle this.. Time to build some LCAs
The joints at either end are made by Currie Enterprises. They have a 2.5 inch DOM shell, a ball pivot encased in two small urethane bushings. They utilize a 9/16 through bolt. The whole assembly is pressed together and secured with a snap ring. These are strong enough for full size jeeps and SUVs that are rock crawling, they will do just fine for this application.
Now, I know what you're thinking.. "But the stock bolts are 14mm not 9/16" ...
9/16= 0.5625 inches
14mm= 0.5512 inches
The 9/16 bolt is bigger, a difference of 0.0113 in diameter (0.00565 radius). For some perspective, thats about 1/90th of an inch difference in diameter.
So I decided I was going to move forward, drill out the factory holes and install 9/16" grade 8 hardware for the new joints.
I picked up some 9/16 hardware and to my surprise, it dropped right through both joints on the MM LCAs that I had. Even more surprising, the 9/16 bolt required no modifications to the axle side mount. It again, dropped right through. Hmm, wasn't expecting that
Im no expert, but if we consider a 14mm bolt, in a 9/16 sleeve on both ends, each with .0113 of difference in diameter. And then add on the axle side that had at least that much. Were looking at 0.0339 in slop across those 3 connection locations. Thats 1/20th of an inch. Not a huge number, but significant. Just imagine it like using a 13mm bolt instead of the 14s - none of us would do that....This sealed the deal for me for sure. Of all the cobras and mustangs with clunks, I wonder how many of them could be corrected here. Nearly a mm of slop across two mounting locations
Any who, ran a 9/16 bit through the body side LCA mount. Notched some tube, welded the ends on. Added a spring plate and sway bar mount. Voilla!
This is before welding, you can see the 9/16 hardware chilling in the MM arms. And It wasn't forced in them by any means
I didn't take any great pictures of the new arms after installing, but this is what they look like. I moved the spring perches forward a little to better align them vertically with the upper spring retainer with a car this low. New urethane isolators on from AM
These also eliminated all of the bind that occurs in the LCAs. They have pivot capabilities at both ends where as the MM LCAs I had only has one spherical end and that was surrounded by a urethane bushing as well.
I did consider that since both sides could pivot, what would keep the LCA from rotating on the joints and potentially dumping the spring. I did some searching online and found several suppliers who sell LCAs with flex joints at both ends that use standard springs (some with sway bar and some without) so I figured I was safe to move to a testing spot. MM specifically uses the urethane bushings around the spherical ones for this purpose however, so I was skeptical.
Once installed for a test fit, i mounted the springs and put weight on the axle. I kicked and pried on the sway bar mount (no sway bar attached) and could not get the LCAs to rotate with the spring pressure on them. Additionally, the sway bar will keep them upright once installed. I do not believe there is an issue here at all. To be safe, the center of the lower coil cup was doubled in height to prevent the coil from taking a walk off.
So now with bolts in the right holes and tight tolerances all around, with spring isolators back in and everything buttoned up.... Wow. The car feels totally different. Not a noise, its solid and handles beautifully. The rear still wags a bit since I haven't yet built a pan hard bar, but its much more predictable and consistent. Theres definitely more noise transmitted into the car with the different bushings though at highway speed
50 hard winding road miles on them and no issues with the springs.
Now I'm not saying that everyone should build a set of control arms. But at least if you do, know that the modifications are minimal to use 9/16 hardware and there is a plethora of 9/16 through bolt poly, spherical, heim etc joints out there to use as replacements. Id be really curious to see who can fit 9/16 hardware through some factory mounting holes and LCAs/IRS subframes
Thanks for checking in, ill post more pics when I can
And BTW, kudos to Maximum motorsports for great parts and phenomenal customer service. Ive got a ton of there parts on this car and I really like there stuff. These just weren't doing it for me
Bill
Heres my setup:
MM LCAs (less than 2k miles)
New factory UCAs
Bilstein HDs
Steeda Springs
Stock sway bar
No isolators
While finishing up my fender roll last week, I peeked under at the LCAs to see how they were doing. Last year ish, MM sent me new LCAs because the urethane front bushing was annihilated for some reason with less than 5k miles on them. Since installing those, my car has seen less than 2k miles. Its a street car with just bolt ons. I can clearly see that the bushing has been allowing the LCA to move forward and back quite a bit. The debris and grease inside the torque boxes is pushed clean around the bushing, 1/4+ inch in each direction.
Now, this is the type of significant deflection I saw last time when I found that the bushings were split inside. So I tore apart the rear suspension, popped the bushings out and surprisingly, they were completely intact. Either way, I'm unhappy with what I see and have been experiencing, so its time to look into some different arms...
A quick web search shows me that replacements with spherical joints at both ends are gonna run me a lot of money. And... Im not 100% sure theyre what I want.
Fortunately, Ive had some special bushings clunking around in my toolbox for some time. And, I've got the tubing lying around to tackle this.. Time to build some LCAs
The joints at either end are made by Currie Enterprises. They have a 2.5 inch DOM shell, a ball pivot encased in two small urethane bushings. They utilize a 9/16 through bolt. The whole assembly is pressed together and secured with a snap ring. These are strong enough for full size jeeps and SUVs that are rock crawling, they will do just fine for this application.
Now, I know what you're thinking.. "But the stock bolts are 14mm not 9/16" ...
9/16= 0.5625 inches
14mm= 0.5512 inches
The 9/16 bolt is bigger, a difference of 0.0113 in diameter (0.00565 radius). For some perspective, thats about 1/90th of an inch difference in diameter.
So I decided I was going to move forward, drill out the factory holes and install 9/16" grade 8 hardware for the new joints.
I picked up some 9/16 hardware and to my surprise, it dropped right through both joints on the MM LCAs that I had. Even more surprising, the 9/16 bolt required no modifications to the axle side mount. It again, dropped right through. Hmm, wasn't expecting that
Im no expert, but if we consider a 14mm bolt, in a 9/16 sleeve on both ends, each with .0113 of difference in diameter. And then add on the axle side that had at least that much. Were looking at 0.0339 in slop across those 3 connection locations. Thats 1/20th of an inch. Not a huge number, but significant. Just imagine it like using a 13mm bolt instead of the 14s - none of us would do that....This sealed the deal for me for sure. Of all the cobras and mustangs with clunks, I wonder how many of them could be corrected here. Nearly a mm of slop across two mounting locations
Any who, ran a 9/16 bit through the body side LCA mount. Notched some tube, welded the ends on. Added a spring plate and sway bar mount. Voilla!
This is before welding, you can see the 9/16 hardware chilling in the MM arms. And It wasn't forced in them by any means
I didn't take any great pictures of the new arms after installing, but this is what they look like. I moved the spring perches forward a little to better align them vertically with the upper spring retainer with a car this low. New urethane isolators on from AM
These also eliminated all of the bind that occurs in the LCAs. They have pivot capabilities at both ends where as the MM LCAs I had only has one spherical end and that was surrounded by a urethane bushing as well.
I did consider that since both sides could pivot, what would keep the LCA from rotating on the joints and potentially dumping the spring. I did some searching online and found several suppliers who sell LCAs with flex joints at both ends that use standard springs (some with sway bar and some without) so I figured I was safe to move to a testing spot. MM specifically uses the urethane bushings around the spherical ones for this purpose however, so I was skeptical.
Once installed for a test fit, i mounted the springs and put weight on the axle. I kicked and pried on the sway bar mount (no sway bar attached) and could not get the LCAs to rotate with the spring pressure on them. Additionally, the sway bar will keep them upright once installed. I do not believe there is an issue here at all. To be safe, the center of the lower coil cup was doubled in height to prevent the coil from taking a walk off.
So now with bolts in the right holes and tight tolerances all around, with spring isolators back in and everything buttoned up.... Wow. The car feels totally different. Not a noise, its solid and handles beautifully. The rear still wags a bit since I haven't yet built a pan hard bar, but its much more predictable and consistent. Theres definitely more noise transmitted into the car with the different bushings though at highway speed
50 hard winding road miles on them and no issues with the springs.
Now I'm not saying that everyone should build a set of control arms. But at least if you do, know that the modifications are minimal to use 9/16 hardware and there is a plethora of 9/16 through bolt poly, spherical, heim etc joints out there to use as replacements. Id be really curious to see who can fit 9/16 hardware through some factory mounting holes and LCAs/IRS subframes
Thanks for checking in, ill post more pics when I can
And BTW, kudos to Maximum motorsports for great parts and phenomenal customer service. Ive got a ton of there parts on this car and I really like there stuff. These just weren't doing it for me
Bill
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