Q: Will this improve traction off the line?

It helps by keeping the rear wheel located under hard acceleration. When the stock rubber bushings deflect, the contact patch shifts slightly and the car can feel less planted launching all that power. A rigid upper fore link holds the geometry, so the tire stays where it should. On a 1,020hp Plaid that already struggles to use its output, tighter rear location is a meaningful gain, and it is one reason this arm is bundled into our full suspension package.