MCA Suspension "Traction Mod"

[NoHaveMSG]

Originally Posted by gpvecchi

What are the defects of this mod?

Actually I think my above response is wrong. I remember that spacing the sub frame to reduce anti-squat would have a negative effect on roll center, but since the MCA mod is just changing the mounting point for the trailing arm it probably doesn't have the same effect on the whole rear suspension setup and it's roll center.

[Joe-G]

If MCA is hard to get, this is an alternative. (not sure if its been shared yet)

Not sure if its any good though...

When the trailing arm of Toyota 86 / Subaru BRZ is installed in the genuine position, the tires move diagonally backward when the suspension sinks by lowering the vehicle height or stroking. Therefore, the wheelbase of a vehicle that has been lowered due to harmonic drive will be longer than that of a standard vehicle. The traction member collar is corrected so that the tire moves vertically by lowering the mounting position of the traction rod (trailing arm), which is the axis of rotation, and adjusting the rotation trajectory of the rod. By installing this product, it is possible to bring out more stable traction performance while fulfilling the same function as "Rigid member color".

https://www.gpsports-gallery.com/products/3727/

[solidONE]

Thats how I used to paint my RC cars. Except in rasta colors. lol

[PulsarBeeerz]

Originally Posted by NoHaveMSG

Actually I think my above response is wrong. I remember that spacing the sub frame to reduce anti-squat would have a negative effect on roll center, but since the MCA mod is just changing the mounting point for the trailing arm it probably doesn't have the same effect on the whole rear suspension setup and it's roll center.

I would assert that the roll center isn't changed much but does indeed give the feeling of a softer rear end. With the rear trailing arm close to level and dipping below level in hard bends you can feel the outer rear tire load up progressively and push you through the turn with added stability. Seems to ride better too, which is nice.

[Joon525]

Originally Posted by Joe-G

If MCA is hard to get, this is an alternative. (not sure if its been shared yet)

Not sure if its any good though...



https://www.gpsports-gallery.com/products/3727/

That last diagram is the best non-verbal explanation of why these types of products are made that I've seen.

It should be noted that by going this route you are applying solid metal inserts into the bottom bushings of the subframe. The silver pieces are for the rear mounting points while the front brackets have the insert built in.
I'm not saying it's a bad thing but if someone already has a ton of bushing replacements back there this could possibly send you over the edge of comfort (unless of course....racecar).

[norcalpb]

Random question. But if you guys had to choose between a trailing arm relocation kit, or keeping Verus suspension covers, what would you do?

I can't add the traction mod without cutting away at the covers.

[gpvecchi]

Originally Posted by Joon525

That last diagram is the best non-verbal explanation of why these types of products are made that I've seen.

It should be noted that by going this route you are applying solid metal inserts into the bottom bushings of the subframe. The silver pieces are for the rear mounting points while the front brackets have the insert built in.
I'm not saying it's a bad thing but if someone already has a ton of bushing replacements back there this could possibly send you over the edge of comfort (unless of course....racecar).

I think the silver bushings are for front subframe bushings in the upper position. I have a friend in Japan who fitted them, and he said that back raises a lot.
I have the STi bushings, and upper STi spacers, that is tolerable for street use, but fitting lower spacers too kills your comfort.

[Joon525]

Originally Posted by gpvecchi

I think the silver bushings are for front subframe bushings in the upper position. I have a friend in Japan who fitted them, and he said that back raises a lot.
I have the STi bushings, and upper STi spacers, that is tolerable for street use, but fitting lower spacers too kills your comfort.

I'm pretty sure they are for the rear....the upper bushings aren't even the same shape.
Look at the shape of the silver inserts and then compare them to the attached images of the Whiteline inserts/instructions.
Only adding inserts to the front and leaving the rear stock doesn't sound like a great idea.

Not looking to derail this thread into a bushing discussion anymore than this though.

[Thefalls]

It looks like the bushing inserts are a direct copy of the WL inserts or vice versa. In the literature for the gpspworts traction arm it also mentions this "By installing this product, it is possible to bring out more stable traction performance while fulfilling the same function as "Rigid member collar".

It looks like its better to install this part than the bushing inserts and still maintain the 'comfort' ( read as less noise ). But then the subframe will still move around a bit.
If someone makes a video with either traction mod, MCA or the gpsports, in combination with the stock bushing then we may have a clear view.

But the thing is, each achieves traction through different routes. But both can be done together? Do they have an additive effect?

It doesn't seem to be for everyone, since not everyone is looking for so much traction in the rear. Some of us like to have a loose rear end for some fun whereas some people need better rear traction for competition purposes.

[e30cabrio]

Suspension mounts came. It was hard to order but they came three days later!

Really well packed & stickers!

[e30cabrio]

Put them in, no added NVH or anything negative, the car felt pretty planted before so I'm not sure if there is any benefit but I'm happy.

[solidONE]

Originally Posted by e30cabrio

Put them in, no added NVH or anything negative, the car felt pretty planted before so I'm not sure if there is any benefit but I'm happy.

Define "planted". Rear end behavior over mid corner bumps? Corner entry? On the throttle?


Seems like this would make the rear end less dramatic and more predictable through the suspension stroke. Feels like a good mod in my mind. Enough to want to test it out. lol Those red and black ones look snazzy, i'm sure the price tag matches.

[e30cabrio]

I only drove about 40 miles. The car has a Nameless header, heimholtz overpipe, catback, P-Tuning flex fuel ECUTEK tune, Eibach sports, Konis, Blox sways, Whiteline endlinks 235 45 17 GT radials so it is well sorted. It's hard to tell from that short trip what these changed.

I'm waiting for 18" GRAM LIGHTS 57DR & Continental ExtremeContact Sport 235/40ZR18.

The Gram Lights are back ordered until at least May.

[e30cabrio]

After about 80 miles more the car hooks up better and stays much more firmly planted during all manner of changes in direction and from changing road conditions. Worth every penny!