Grounding Cylinder Head Test Results (2024 CX-5 Turbo)

AL Cx5

2024 CX-5, Prem, Turbo, Tuned, Forged Wheels
I added a ground wire from the cylinder head to the chassis on our 2024 CX 5 T. I've been doing this mod on other gas burners for many years. 90% of the time it has product gains in power and gas mileage. On newer cars, the ground systems have improved so I was curious what would happen on the Mazda.

In the past I use to measure at WOT much like the other aftermarket folks. Until today, I never ran a road test. I have a section of interstate I can run on CC and log the results on my phone using Torque Pro. This is where I ran the test today, with and without the grounding.

On my DD, partial throttle testing is what I want. Venders post WOT tests and I have wrongfully assumed it translated to partial throttle. Much latter I learned to test at partial throttle.

TORQUE logs a data point every 0.01 second. It will send a CVS file to my email and then I transfer it to a spread sheet.

The results were mixed. Over the course which has a variety of terrain there was not much difference.

Next I isolated where the engine was over 40% load going up a hill. The grounded test scored 3.76% better than no ground. This correlates to my WOT dyno tests on a stock 06 5.7 Hemi. At WOT the Hemi got closer to 5% gain. We got a back up Dyno on another car and dyno latter and it had the same improvement.

I had to twist a guys arm to run a backup dyno test back in the day. He said that he didn't want to hurt my feelings. After he ran the test he called and said, "you want believe this, the grounds produced X more power!"

Soon after I grounded my wife's 09 Accord, 2.4 NA. She came in that night and said, what did you do to my car? I said I had grounded it and would take it off. She said, NO, I like how it drives...

Disclaimer: I'm not selling anything or affiliated with any vender who makes this device. Take or leave it...
06 Dodge Charger, 5.7 V8
grounding dyno 5.7 Hemi.png

6.1l NA stock Hemi
Note the low end it made 18 more HP, right were a DD needs it.
OST grounding dyno.png

2024 CX 5 Turbo. This Y axis is time in tenths of a second. The X axis is Engine Load, going up the same spot on a hill on CC at 55 MPH.
Mazda ground graph.png
 
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This has to be the easiest install, ever.

I hope someone else will do this mod and log their results at WOT....

0506241700a_HDR.jpg
0506241700_HDR.jpg
 
I'd like to know more but why am I not finding dozens of YouTubers doing this :unsure:
I suggest you do your own test and determine for yourself. You seem to be looking for more power from bolt on parts. Here is a cheap 10 to 15 HP.

When we use to race in a class, we were looking for every HP and stumbled on to this. It was worth a few hundredths of a second in the 1/4..

Investing in a OBD2 Bluetooth transmitter so that you can log data to your phone will be handy to check future mods and confirm or not confirm the above.

If you have to find dozens of examples, then this is not for you.

I've attached a ground to the throttle body and picked up the same amount. You might find enough folks doing it this way to venture out and try this. 😄

A small leap of faith is required...
 
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I understand the first graph of the Dodge Charger HP and torque. Why does the baseline max torque show 426.0 ft/lbs in the table for the "baseline" but the graph shows torque always below 400 ft lbs ?

For your second chart/graph listed as "2024 CX 5 Turbo", what am I looking at? "60" (what) on the X axis and "time" on the Y axis. I don't understand what I'm looking at / what does this tell me?

I have heard of folks through the years of doing bigger and/or additional ground straps to the engine. What does this do electrically / mechanically to make the engine run better? Why is the engine happier with a better ground? Thinking maybe coils and spark energy is the only thing that comes to my mind.

With something like this, I think about auto manufacturers spending millions on R&D to eek out every gain of efficiency no matter how small. So why would automotive engineers leave a gain in power and efficiency from better grounding on the table? There doesn't seem to be a downside (higher emissions ?) that would make the manufacturer not do this.
 
I understand the first graph of the Dodge Charger HP and torque. Why does the baseline max torque show 426.0 ft/lbs in the table for the "baseline" but the graph shows torque always below 400 ft lbs ?

For your second chart/graph listed as "2024 CX 5 Turbo", what am I looking at? "60" (what) on the X axis and "time" on the Y axis. I don't understand what I'm looking at / what does this tell me?

I have heard of folks through the years of doing bigger and/or additional ground straps to the engine. What does this do electrically / mechanically to make the engine run better? Why is the engine happier with a better ground? Thinking maybe coils and spark energy is the only thing that comes to my mind.

With something like this, I think about auto manufacturers spending millions on R&D to eek out every gain of efficiency no matter how small. So why would automotive engineers leave a gain in power and efficiency from better grounding on the table? There doesn't seem to be a downside (higher emissions ?) that would make the manufacturer not do this.
Manufacturers are trying to save every $0.01 they can. They are also trying to save every gram of weight they can. There are miles of copper wire in a vehicle, they try to reduce it as much as possible.

They apparently feel the juice is not worth the squeeze.
 
I agree, and to be clear: this is how it should be done. Not through subjective assessments and butt-dynos, but real data before and after the change.

In my searching I did find some discussions on various boards dating back to 2004 and 2005, but not much since. I understand some of the reasoning why it could work, but I'm left with the same question as @HyFlyer.
 
I'm guessing, if this works, that maybe the ground is siphoning off the electronic noise from the engine management system, allowing better data flow between electronic modules making things more efficient? I dunno. Also agreeing with HyFlyer. I'm told that the head, head gasket, and block acts like a capacitor ,and the ground strap is an electronic siphon.
 
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For those who need to know why. Do you KNOW what a tuner has done to you ecus tune to make more power. I have an idea but don't know or care about the derails. Still folks buy tunes.

I'll post what guage wire used latter. I'm using high quality marine grade cable that I made up. This is NOT required. My first grounds in 2010 war made from stereo cable. Welding cable and such work too. Multi strand copper is the key. Even parts store ground cables work.

Why it works: more than likely because the fuel injectors and coils fire off a ground signal from the Ecu. There is a small lag time when the edu sends the signal and when these devices fire.

I tried this mod on a 2022 Alfa and couldn't tell any difference. A Chrysler V6 was a bust as well. But all the Gen 3 Hemis it worked. So far all the Asian cars and trucks it has worked so far.

As mentioned, I was curious if it would work on a 2024 CX 5.

As far as the dyno graph. The torque number was a software error. This was not a high quality dyno. The results, curves, were duplicated on my friends Mustang dyno. I'll look back for this test.

The CX 5 graph is engine load vs time in 10ths of a second. I found that engine load is a good measurement. I'm carefully to be on CC, start and stop at the same point. I've used this method for several years running my Ram, 5.

Glad to see some folks looked at the graphs! 😁
 
I found the independent ground test by OST Dyno. Please view it in Post #1. This was on a Loaded, Eddy current dyno. It is one of the most accurate on the market.

Of interest, at lower RPM it makes the most power. The dyno software noted min, max and average.

At Min HP gain 18 HP, At Max HP a gain of only 4 HP. Average 6 HP. This is repeatable on other tests and should apply to our platform, NA and Turbo. AT 3230 RPM the grounded engine made 16 more HP than non grounded.

What this means for a DD, when driving in stop and go traffic the engine produces more power right where it's needed. For drag racing it mostly helped at the start when launching the car.
 
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Would be interesting to see others try this. @sinistriel@ has had his car on the dyno. I want to eventually but I need to locate one.
Gee, this is a 15$ mod. It takes more time to get out a 10mm socket than it takes to put it on the car. HP/Dollar is the best deal going. We picked up 3 MPG on the Honda. It saved us from $250 to $300 per year in fuel. Not a home run, just a single that kept working until my daughter got it 14 years later.

I use to make up kits for the Gen 3 Hemi guys. It didn't make much money but put me in the professional class. It wasn't worth it so I stopped making them. For those who don't work with wire, the parts stores sell ground cables that work.

If there is not a dyno next door then improvise. There are dyno software/apps that do a great job estimating HP on the street. I use to do this to test stuff like spark plug heat range, gap and ECU tune revisions when I had a street rod. The street dyno mirrored a chassis dyno HP change within a few percent. I scaref a few folks when I would come up behind them at a high rate of speed, then duck off at the exit ramp. Then rent a chassis dyno and it confirmed my software.

The few times I've logged WOT on our 2.5t was not dangerous and barely over the speed limit. These are not fast cars. So this method would work very well. My tuner requests 2 short WOT pulls before doing a revision. WOT in my CX 5 T doesn't blow my skirt up.

I don't feel called to prove grounding works. I could wear out my CX 5 doing tests and still folks sit back on their keyboard and claim it doesn't work or need more data. Mean while I'm saving 300 to 500 per year, year after year. We put 5k mi on the CX 5 to date. I estimate this ground saved us $122.00. Run that out over 100k mi is $2400.00. Not a home run but some pocket change.

I call it Herd mentality. It occurs on forums. Even some of the smart guys on this forum follow the herd rather than evaluate, think outside the box or try something they don't fully understand.

As posted on this forum, our 2.5T beat Mazda's highway estimate, 27, over a 1500 combined highway in town driving, 31.5 hand calculated. We didn't hyper mile, and let it eat going up mountains.

While folks are wringing their hands over a $15 mod, I'm on to something some other fun mods.

Cheers!
 
We picked up 3 MPG on the Honda. It saved us from $250 to $300 per year in fuel.
In before others say it: automakers are bending over backwards to meet fleet fuel economy standards and they miss a $15 ground?

Now you may not have proof from the last 15 years when people ask for it. However, there's no need because this works both ways. Simply disconnecting the wire should result in a drop of 3 mpg. That's about a 50 mile reduction in range per tank. I will be shocked if that happens because I don't understand physically how it's possible.
 
And a tune, CAI help FE too. Except these cost way more.

My A to B road test show an improvement.

Please get off your keyboard and prove me wrong. I'll be the first to congratulate you.
 
I mean, either it works or it doesn't. It would be great to know how it could work and why it works on some cars and not others, but this is a fairly low cost modification to implement. Could be "snake oil", but its not in the same vein of things like electronic rust prevention modules. As far as I can tell, it's low risk, low cost, and easy to try. I would love for someone else to try it and will be watching this thread until I actually try it myself on my CX-9.

I will note that one of the forums I used to frequent in my youth, over 20 years ago, was a 90-93 Honda Accord forum where a "Big 3 Grounding Kit" was considered a "mod". In that case, people regularly reported smoother idles and a slight improvement in throttle response. I never tried it myself though. A quick Google search shows lots of forum discussion around this topic in the early-to-mid 2000s. It doesn't seem to be as popular of a mod as it used to be, that's for sure.
 
I mean, either it works or it doesn't. It would be great to know how it could work and why it works on some cars and not others, but this is a fairly low cost modification to implement. Could be "snake oil", but its not in the same vein of things like electronic rust prevention modules. As far as I can tell, it's low risk, low cost, and easy to try. I would love for someone else to try it and will be watching this thread until I actually try it myself on my CX-9.

I will note that one of the forums I used to frequent in my youth, over 20 years ago, was a 90-93 Honda Accord forum where a "Big 3 Grounding Kit" was considered a "mod". In that case, people regularly reported smoother idles and a slight improvement in throttle response. I never tried it myself though. A quick Google search shows lots of forum discussion around this topic in the early-to-mid 2000s. It doesn't seem to be as popular of a mod as it used to be, that's for sure.
Back then every HP improvement could be felt. They only made 140 HP way up at 5200 rpm.

Our 2.5l makes decent low rpm torque and the change is not as easy to feel. Add a turbo and one has to have a sensitive butt dyno to tell a difference.

Same old argument is still used. The manufacture would surely have thought of this.

The data suggests other wise. I ran the A to B tests to confirm or not it helped. I simply posted my test and FE results to help our community. I'm not promoting or selling anything.

I so love dealing with folks whos first word out of their mouth is no, it won't work.

So, I'm signing off from this post. Take other leave it. I have way better things to do.
 
I do appreciate AL Cx5 taking all this time to present his knowledge and research to the forum. I'm in the snake oil camp because I've tried this with my other not so modern car and I couldn't feel anything despite the high praises on the forum. Maybe this is for people that live a quarter mile at a time, but definitely not for everyday driver.
 
This YT guy seems to be impressed by it.
$25 with HKS kit.
Installation video.

In EE (electrical engineering), these is the thing called ground bounce. (also happens in semiconductor/IC chips)

Thought the body is the ground in an automobile, when you contact the body at diff point, the voltage is not zero (relatively speaking). It would be slightly higher than relative 0.
When you add more connectors to pull voltage of contact points down to relative zero volt, this increases the voltage difference at each part... positive 12v remains similar, I assume.

Effectively, you increase the voltage difference (12v wrt 0v) at the electrical device, which make the device reacts better/faster as higher voltage is supposed to.

This voltage pulldown also helps calm down noises (ground noises) that are introduced by various devises on the vehicle. Maybe that is why audio sounds better.
Anyway, my two cents on this.

I would love to see more scientific data as many of you do.
 
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