DarkLight
Senior Member
- Joined
- Apr 21, 2016
- Threads
- 13
- Messages
- 606
- Reaction score
- 563
- Location
- LA
- Vehicle(s)
- Civic-2016 LX 6MT
- Thread starter
- #1
To start, the 6MT Civic LX comes from the factory with a soggy shift assembly. The engagement is neither positive nor crisp. It almost feels misaligned. When stepping on the accelerator, you can feel the engine wind up in its’ mushy mounts as the rpm’s build, and feel as the car’s drivetrain hesitates before it surges forward. Trying to power shift at high rpm’s during hard launches is hardly confidence-inspiring as the excessive wheel hop and driveline lash causes the traction control to go bonkers and bog the engine down. And even if you turn off the TC, you’ll just grimace as the tires squeal horribly and leave an awful skid mark in your wake, while going nowhere fast.
All done in the name of reducing Noise, Vibration, and Harshness – or maybe Honda is just cruel and doesn’t want us to have any fun . Of course, why else would you buy a 6MT Civic?
To remedy this, we need to get a few items from the OE parts bin and swap them out, after a small modification that is.
P/N’s you’ll need:
50890-TBA-A82 – Torque Rod $31.88
90108-TL1-G00 – Bolt 4.76
90161-T5A-000 – Bolt, Flg 4.77
Basically, we’re taking our torque rod (aka “dog-bone”) and swapping it with the torque rod from the CVT cars. The reason that the rod from the CVT-equipped cars is desirable is because the bushings are stiffer and will allow less slack in the drivetrain. However, before installing it, a modification needs to be made to the rear bushing of the rod.
The larger rubber bushings allow more play. (Sorry, did not take a before pic of the unmodified CVT mount.)
At this point, you can either use my method, or fill the mount with 3M Window-Weld, which is a polyurethane sealant that is roughly equivalent to the OE bushing’s hardness/stiffness (plenty of online tutorials for that).
For my method:
My method is different in that it uses rigid inserts that allow slight movement under light load, such as upshifting/cruising on the highway to reduce cabin vibration, but acts as a solid mount under high load by completely eliminating movement beyond a certain point. Also, silicone is utilized, primarily for its vibration dampening properties, to allow a stiffer mount without experiencing the added NVH typically associated with this type of modification.
Tools you need:
Not pictured: basic socket set, 1/8" steel sheet, 1/2" UHMWPE rod, cutting tools
To begin, cut two pieces of polyethylene rod about 2” long and ½” wide. Then, cut two 2” strips of 1/8” thick steel, with the first being 1” wide and the second 3/8” wide. These will be your four inserts that you will press into the bushing. If you don’t have these materials, you can use any type of rigid material that will fit in the respective voids of the bushing. High strength polymer/metal is strongly recommended though.
Next, wrap the inserts with F4 silicone tape, not so tight that it is difficult to tap them in, but enough to create a tension fit. This is point where you “tune” your mount – adding more silicone tape will increase the pre-tension on the mount and reduce travel while less will give the mount a more forgiving feel. Once you have fine-tuned the inserts, coat them with a plastic adhesive and tap them in; if you don’t want to buy the stuff I used, Loc-Tite Extreme, or any generic plastic adhesive, will work.
Allow the adhesive to cure, then apply standard silicone sealant to remaining voids in the mount. After that has cured, install the mount.
To Install:
Jack the front of the car up or put it up on ramps and chock the rear wheels. Then remove the aluminum splash shield fasteners with a screw driver and lower it. You’ll see the torque rod between the rear subframe and the transmission.
When you go to remove the bolts, the first one that is connected to the transmission side of the rod is 19mm, but you’ll need to use a ¾” open end wrench to access it. The other bolt on the subframe is 17mm and is best accessed by cutting a small notch in the plastic part of the splash shield that covers it.
Remove the vertical subframe bolt first, then the horizontal one that goes through the bracket. After a slight pull forward, it should drop right out. Installation is the reverse of removal. I torqued the bolts to 30 ft/lbs and used blue loc-tite thread locker, but 'good-n-tight' should be enough.
After driving it for about 50 miles, I can say that in terms of NVH, it is like stock, except when letting the clutch out in reverse, where there is some noticeable vibration from the drivetrain. Otherwise, performance is noticeably improved under all conditions.
However, the mushy, oil-filled engine mount is still a culprit. That one is next.
Stay tuned...
All done in the name of reducing Noise, Vibration, and Harshness – or maybe Honda is just cruel and doesn’t want us to have any fun . Of course, why else would you buy a 6MT Civic?
To remedy this, we need to get a few items from the OE parts bin and swap them out, after a small modification that is.
P/N’s you’ll need:
50890-TBA-A82 – Torque Rod $31.88
90108-TL1-G00 – Bolt 4.76
90161-T5A-000 – Bolt, Flg 4.77
Basically, we’re taking our torque rod (aka “dog-bone”) and swapping it with the torque rod from the CVT cars. The reason that the rod from the CVT-equipped cars is desirable is because the bushings are stiffer and will allow less slack in the drivetrain. However, before installing it, a modification needs to be made to the rear bushing of the rod.
The larger rubber bushings allow more play. (Sorry, did not take a before pic of the unmodified CVT mount.)
At this point, you can either use my method, or fill the mount with 3M Window-Weld, which is a polyurethane sealant that is roughly equivalent to the OE bushing’s hardness/stiffness (plenty of online tutorials for that).
For my method:
My method is different in that it uses rigid inserts that allow slight movement under light load, such as upshifting/cruising on the highway to reduce cabin vibration, but acts as a solid mount under high load by completely eliminating movement beyond a certain point. Also, silicone is utilized, primarily for its vibration dampening properties, to allow a stiffer mount without experiencing the added NVH typically associated with this type of modification.
Tools you need:
Not pictured: basic socket set, 1/8" steel sheet, 1/2" UHMWPE rod, cutting tools
To begin, cut two pieces of polyethylene rod about 2” long and ½” wide. Then, cut two 2” strips of 1/8” thick steel, with the first being 1” wide and the second 3/8” wide. These will be your four inserts that you will press into the bushing. If you don’t have these materials, you can use any type of rigid material that will fit in the respective voids of the bushing. High strength polymer/metal is strongly recommended though.
Next, wrap the inserts with F4 silicone tape, not so tight that it is difficult to tap them in, but enough to create a tension fit. This is point where you “tune” your mount – adding more silicone tape will increase the pre-tension on the mount and reduce travel while less will give the mount a more forgiving feel. Once you have fine-tuned the inserts, coat them with a plastic adhesive and tap them in; if you don’t want to buy the stuff I used, Loc-Tite Extreme, or any generic plastic adhesive, will work.
Allow the adhesive to cure, then apply standard silicone sealant to remaining voids in the mount. After that has cured, install the mount.
To Install:
Jack the front of the car up or put it up on ramps and chock the rear wheels. Then remove the aluminum splash shield fasteners with a screw driver and lower it. You’ll see the torque rod between the rear subframe and the transmission.
When you go to remove the bolts, the first one that is connected to the transmission side of the rod is 19mm, but you’ll need to use a ¾” open end wrench to access it. The other bolt on the subframe is 17mm and is best accessed by cutting a small notch in the plastic part of the splash shield that covers it.
Remove the vertical subframe bolt first, then the horizontal one that goes through the bracket. After a slight pull forward, it should drop right out. Installation is the reverse of removal. I torqued the bolts to 30 ft/lbs and used blue loc-tite thread locker, but 'good-n-tight' should be enough.
After driving it for about 50 miles, I can say that in terms of NVH, it is like stock, except when letting the clutch out in reverse, where there is some noticeable vibration from the drivetrain. Otherwise, performance is noticeably improved under all conditions.
However, the mushy, oil-filled engine mount is still a culprit. That one is next.
Stay tuned...