The ground wires are pretty beefy in the MK3s. I did do it to one of my Hondas along with an Interstate battery with the lowest CCA available at the time and the difference was huge. Power delivery and gas mileage were greatly improved. I was hitting 44 mpg on the highway with an engine with 160,000 miles on it.

 

I'm just curious I guess since there seem to be so many electronics related issues with the Mk3, perhaps the stock grounding isn't enough, especially for MFT equipped vehicles. One thing I've learned with building computers is that when the PSU can't provide the juice, the hardware bugs out and the system will freeze...

Adding to the beefier grounds discussion, has anyone done a fused Bat+ cable directly to the alternator+? Or is this possible on a Mk3?

 

I had to look up big 3 as I was not sure what it was. For those that don't know, it's changing your Negative Cable (Battery - To Chassis), Positive Cable (Alternator to Battery +) and Engine to Chassis wires with bigger, beefier ones.

The ones in the MK3 are relatively big compared to some cars but I think there is room for improvement. Where is our engine to chassis wire? I haven't really went looking for it so I don't know how beefy it is. Replacing these and maybe adding another engine to chassis ground wire might be a good idea. Especially for people like me who have a hard wired radar detector in the system, or people with aftermarket subs.

I think I'll look into this a little more..

 

I had to look up big 3 as I was not sure what it was.

For reference, I posted a link above for anyone not familiar with it. It's a lot of posts but there's plenty of information there. [woot]

 

Isn't the batt to chassis ground the lug on the firewall? That one has an 8 ga ~ish wire feeding it. Plenty beefy! If the rest are similar, I'd say well done Ford. I'll dig around when I do my oil change this weekend and scope out these wires

 

I did the Big 3 upgrade on my MK3 because of the I'm running a nice after market system and I've done it on all my vehicles. The kit I got was by NVX that I bought at Sonic Electronix below is the link of what I bought.
http://www.sonicelectronix.com/item_72349_NVX-Big-3-Package.html

 

Wow, that is overkill for most members here who are interested in trying it. You can definitely get away with 4-6awg cable.... But if you've got a huge sound system I guess that kit would be valuable at any price.

 

Wow, that is overkill...

I forgot to mention in my original post...I was running 0g that I had made for $10 and lead racing battery terminals.

 

Interesting sounding mod, I didn't know what it was at first either, and shouldn't be too tough or expensive. Decent peace of mind at bare minimum.

 

Everything that I've looked at says that this is primarily for audio gains. Does this mod really hold any performance gains?

 

It's debatable on actual power gains (some have shown proven dyno results), but so far all information available in the archives shows that people who do this type of modification see improved driveability and smoother power delivery.

My main curiosity in asking is with all the problems revolving around DCT, MFT, EPAS, TBW, TC, ESC, etc, would reinforcing the electrical delivery system have any effect on how these systems function? With so many systems wired into the car, it must be possible that interference/resistance can play a role in malfunctions.