Yes it will help your car performance...I recently installed a Home Made
Grounding Kits..there's a lot of HKS and other grounding kits in the market that will cost you around US$35.00@ middle level quality while the hi-end will cost you around US$60.00. You do not need to spend a huge amount on this, I used a multiple strand wires ( fine wire) with a very good insulation that can stand the 250 temp. and bought a silver plated terminal for a minimum cost of US$.50 cents and shrinkable tube to firmly holds the terminal and the wire after pressing the wire into the plated terminal.
My car is a Honda Civic Vtec 1996, I only replaced at the moment the Original 3 points grounding kits intalled by the OEM which is due for replacement and when I started the car after replacing them, you can easily distinguished that the Car Starting Improves,Car Stereo Sounds was a lot better, Acceleration Response also improved coz of the Good Conductance of the New Home Made Grounding Kits, Headlights was a lot Brighter than before.
Will add an additional 1-2 Grounding Wires this coming week end from the Negative Terminal to fully improve the conductance of the Grounding Wire from Negative Terminal>chassis> engine blocks. Will share the performance after doing it.