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Apexi super voltage stabilizer 5.7

21K views 103 replies 25 participants last post by  brentwoodkris 
#1 ·
I just installed the Apexi this morning, and after test driving at all speeds and WOT, no doubt the Hemi runs smoother, quieter, thorttle response is better, and I can't tell at all when MDS is on now. At slow speeds around 30 under light throttle when MDS is on, it responds instantly with no hestiations nowm and for some reason, the trans seems to shift better too. I expect mpg will improve also. Mounted it up on drivers side, just in front of the brake master cylinder, took 30 minutes or so. http://importperformanceparts.net/imports/apexi-groundstable.html
 
#2 ·
Guys, this is one of the few mods that I've tried that is worth the $. Several have dyno tested these and seen 9-14 whp increase throughout the rpm range, and that is on small displacement Hondas, Scubies. I'm not going to dyno test but seat of the pants estimate is 15-20 whp on the Hemi, which is noticably smoother, quieter, and the trans also responds and downshifts quicker. It looks cool under the hood too, with the glowing red LED Apexi logo.
 
#3 ·
I know most of the engine/trans. sensors are "voltage sensitive", and can cause erratic operation due to over/under voltage or spikes. Where did you hook up all the grounding/bonding wires? How many are there? How long did it take? Are there specific instructions for the Jeep electrical system, or do you have to hunt down the points? Keep us posted on any other improvements noted.
 
#6 ·
Linky to the instructions to do it on the cheap for the WK?
 
#5 ·
Hmmm, we should get a group buy going on these. $209 is a bit pricey IMHO.
 
#7 ·
Im down for a group buy. I really want this. I believe the voltage stabilizer works by using thicker cabling from the negative side of the battery which conencts to two places: Frame of the car and engine. I believe the voltage stabalizer also connects to the positive side of the battery
 
#8 ·
The Apexi connects to both the positive and negative terminals on the battery , and then has 3 other ground wires. I connected the 3 to the alternator, engine head, and frame ground just south of the battery, and those are the results posted above. I just switched the alternator one to the top left bolt on the ported TB this morning and will see how it compares over the next week, as I've heard TB grounding may be helpful too. The engine head already has a tapped hole on the drivers front side, so I just put a bolt in there with the ground wire. It runs great both ways, smoother / quieter at all RPM with more pickup.
Not sure how to post a pic here, but I mounted the box horizontally (this is reccomended) in front of (towards front of vehicle) the brake master cylinder.
The red LED stays on all the time; LED's use so little power that it does not drain the battery.
 
#11 ·
all these "high tech" jdm parts are simple DIY. pretty much do a ground mod run multiple ground wires..... that alone helps...
this apexi reminds me of a capacitor...like u would use on a sound system..
and butt dyno are missleading... its just a feeling
Turbo charged G2X using tapatalk 2

It's been dyno proven many times, and no doubt it is quicker, smoother and quieter. No the butt dyno is not misleading, it surely runs better. From all the mods etc.. I have done, The most beneficial/ cost effective you can do to a Hemi, which are all easy to do are
1). Catch Can
2). MM 85 mm CNC ported TB
3). Apexi super voltage stabilizer
4) Seafoam

Total cost of about $ 700, and the engine is very quiet, smooth and faster responding at all RPM. Low end torque is particularly far better which is ideal for street. These will easily blow the doors off any 5.7 WK with a CAI and catback, which are similar cost, and just make a bunch of noise in comparison, from my testing.
 
#13 ·
Idk, to hook this up you have to disconnect the batt. So right there you are resetting the adaptives,and that by itself makes it more responsive- for a while. However, I can see how a more constant,stable elec system can be a good thing.
 
#14 ·
Nope, you do not disconnect the battery to install it. You unscrew the nut on the terminal tight donw bolts and the ground wires attach to the bolts. So many on this site, more than any other I have ever seen, just want to argue with opinions on why something should not work. The results were immediately noticable, very clearly postive across the board. If you want a more responsive engine, that is also smoother and quieter, do this. If you want a loud noisy engine that is slow and unresponsive, put on a CAI and catback, if that's what makes your dingaling feel bigger.
 
#15 ·
Anywhere else to order this from? Perhaps a cheaper vendor? I searched and couldn't find anyone else with it available for sale. Even the mfg page doesn't list that product. Also, the linked site seems shady.
 
#16 ·
Yes the site seems shady or at least really outdated.

But I think dmsfun who has been a forum member for 2.5 years has noting to gain by recommending it, so it could be good to give it a try.
 
#17 ·
I actually bought it from an Apexi dealer over a year ago and found it in the big pile of spare parts for my road race car, so just installed it in the Jeep. Sorry if the link was no good, as I could not find the reciept with the name of the supplier, so did a google search and that link came up as the first listing. There are other listings that might work, here is one, http://www.sfxperformance.com/parts/APE477A903.htm
 
#18 ·
I may be new here but I'm not new to jeeps, internal combustion engines or how they work.
I understand a quieter stereo and maybe better health for all of the electronics with a conditioned power supply but 15=20 horsepower seems a pretty big stretch to me. Hell, so deos 5hp to me.
I've wasted a couple hours trying to research this thing. Its been around for a few years now yet the only places that say it works are sites selling it. I couldnt find anything to prove to me it does anything for performance.
I feel the same about this as most add ons, If it looks cool/makes more noise/your buddy doesnt have one, you have a long diatribe about why it works, charge more than its worth and you can spread the word on the internet...you will make money.
Maybe the Jeep/Hemi combo responds differently. Strictly my oinion but, throw a capaciter in there, check/add more grounds and accomplish the same thing for less than $20 Open the box and see whats in there. I'm a cynic and until I can find more than "but dyno" proof I will spend my money known quantities or more gas.
 
#19 ·
IF you think you can build one for 20 bucks, and get similar results, have fun trying and when it doesnt do much, don't say the Apexi is the same and doesnt do much either. I am the last one who cares about looks and nobody but me ever works or sees under the hood. Yes there is marketing hype with all aftermarket products, and previously I bought into the MAgnaflow and CAI mods, only to find they did nothing but make noise and lose low end, with poorer steetability. I sold those and went back to stock. Then added theMM CNC 85 TB and Apexi which togther alone make it run like never before, plus there is no need for a trans tune. For the first time since Ive owned it new, it shifts and responds great, still on the original fluid. It's now fast. smooth and much quieter sounding, with none of obnoxious intake and exhaust sounds to drown out the sweet Hemi.
 
#20 ·
I'm going to bring this back to life for a moment and say that the theory as to why this works makes sense and is worth doing from what I've learned.

@ SweetWilliam: Not to bust chops, but saying you're not new to how internal combustion engines work or new to Jeeps is kinda like saying you're not new to the concept of flight based on your experience with flying in planes before. I'm sure you know quite a bit about the basics (as many of us do) or even have moderate knowledge on the subject, but the newer Jeeps, especially the ones with MDS, are a completely different animal. That being said, I have serious doubts about a true increase in hp or torque as opposed to the perceived gains based on better response and smoothness and would agree that there is a much cheaper solution to achieve very similar results.

Newer cars are using a "drive by wire" system more commonly where wires and electrical signals replace cables. Some MDS systems, in particular the 5.7 Hemi, use an electronically controlled throttle body along with a bunch of other things that depend on an electronic signal to function. It is no secret that most of these newer cars with "drive by wire" are not as well grounded as they should be and tend to have throttle response issues. I'm sure auto makers choose not to "fix" the issue because of the cost to put more wires in to better ground the system and it helps keep the engine bays neat and tidy.

When it comes to electronics, distance equals resistance and so does the amount of current when compared to the size wires being used. For anyone who's had a decent stereo system setup with an amp and a sub or two, you should know why the wires (especially the ground) are so big. Ideally you want as big and as short of a wire as you can use to help resistance issues. When it come's to a modern engine, that's easier said than done. Imagine water going through a hose, not matter how hard you try, you can only get so much out at one time with breaking anything.

Solution? Add more grounds to help provide more paths for the current to travel and ease the electrical congestion allowing for the signals to move more quickly and efficiently. Apexi has done this for you at a great cost and like others on here have said, it's kinda like a capacitor for an amplifier. Along that same line, it's pointless to hook up a capacitor to your stock stereo, there is no need as the demands aren't great enough. Keeping with this thought process, adding more grounds will help because it's "lacking" grounds to begin with. I saw this brought up on jeepforum back in april and did my research on it and you could totally do one yourself. But if you're kinda lazyish like me, you'll look into something pre-made, but MUCH cheaper than Apexi:

http://www.andysautosport.com/jeep/...ce/ignition/ground_kits/nrg/nrgi00000296.html
 
#21 ·
I realize after reading my post again that I wasn't as clear as I intended on being. The point I was trying to make was that I wouldn't expect to gain HP from the kit, but that it should/will improve how the vehicle performs because the electrical system is running more efficiently and isn't being slowed down or restricted as much. You could easily do this yourself by getting larger ground wires and running them to the same points and it would be cheaper than buying a pre-made kit. I apologize to any and all that was offended by/misunderstood my previous post.
 
#22 ·
It has been Dyno tested many times, and there is an incrase in HP and torque throughout all RPM that can be felt. Other mods generally shift the power curve so any gains are at higher RPM, and low RPM losses are seen. The added benefit to the added power is how much smoother and quieter the engine is at all speeds. If you have not tried it, it really makes no sense to attempt to theorize what it does or does not do.
 
#24 ·
I will preface this with saying it is my opinion. I will also say that I did a bunch of searching around for info because I was bored and intrigued. So it is a researched opinion, not just pulling it out of my azz. lol

It has been Dyno tested many times, and there is an incrase in HP and torque throughout all RPM that can be felt.
All the searching I did came up with zero 3rd party before and after dyno sheets. I did however find a bunch of negative reviews. If you can show me credible info I apologize, but for now I am tired of seeing you push this thing every chance you get.


If you have not tried it, it really makes no sense to attempt to theorize what it does or does not do.
Thats a ridiculous statement. Its not a magic trick. Spending $249 or whatever it costs and running it will make all the answers appear on your "butt dyno"? (I know you found it in a box of parts or something so we should believe you because it was almost free.) Thats BS just like the sales pitch for this shiny little box with an LED or two in it and some wires. Better grounding surely cant hurt with all the electronics and that can easily be done with a few bucks in wire and connectors.
 
#23 ·
Just get dual batteries and upgrade your grounds and you will be set for life :). The one thing that stopped me getting this kit was the led that stays on. I need to leave my car for months at a time and every once of battery power counts lol. Right now I am pushing 2400 amps
 
#25 · (Edited)
Just my 2 cents. I have been in the Electronics industry for over 20 years. Most of you own a computer (unless you are posting on this forum with an abacus), so ask yourself this question: Do I have a surge suppressor on my PC? If so, why? There is as much computing power in our vehicles as in a small tablet PC, much more than when vehicles first started sporting PCM/ECM's. Now if you want clean power for your PC, wouldn't you want clean power for your vehicle? These devices are really just that, power filters. They store a capacitive charge from the battery and absorb nasty spikes, also supplementing power levels when there is a drain. Constant supply voltage is CRITICAL for all electronic components. Ground is just a s critical. The Apexi has just included a ground bus and some fancy marketing. One of the cheap capacitive filters on eBay will also work as long as it has enough "capacitance". The grounding you can do yourself. I just ordered one of the cheapies myself. The TB ground wire mod is along the same concept. And yes, you can protect your computer from nasty voltage spikes with a simple capacitor bank. The main difference here is that on your PC it is protecting and filtering 120vAC and on a vehicle it is 12vDC (Capacitors don't give a rat's butt about current).
 
#26 ·
I Read some of this this morning and did some research and here is a article I found while looking around
http://www.importtuner.com/tech/imp...se_power_and_torque_fact_fiction/viewall.html

I believe it all depends on the car installed. I think it may do some good with systems and lights but doubt it adds any noticeable HP . I believe the grounding is a good thing though. The clear and quicker path to ground is always better

Just my 2 cents
 
#27 ·
MY 2 cents. Every single person arguing about this does not have one. Only if you install one will you then have a viable opinion, and will know how well it works and how much better the Hemi responds.
 
#34 · (Edited)
I had one on my Jeep and am arguing it....well not arguing it, but think it's questionable at best.

I had the wire and some connectors so made a kit myself....things did seem a little smoother but that could simply be from the battery being disconnected and the adaptives resetting, could be all mental...thinking I did something so I should look for the result.
There is a thread on LXForums, someone there makes grounding kits, he has dyno charts and etc...
As for the throttle body grounding....the electronics in the throttle body are isolated from the housing so connecting a wire to it will not do anything.
If you're running grounding wires...don't forget the transmission.

Did a little googling....supposedly this kit is made by NRG, and a little search of NRG gave me this post on s20nation.com

I bought the NRG voltage stabilizer (compact version) I must say it really does work. It doesn't necessarily boost HP but Import tuner mag did dyno 3whp gain on a 2000 Civic Si.

Things i have noticed are my windows roll up easier/quicker. Quicker starts. After sitting for a few days my car would crank over real slow. This has been almost 100% eliminated due to installing the NRG voltage stabilizer. Better throttle response.

NRG claims that it will -

~ Battery Lifespan will become longer
~ Stabilize Idling
~ Lesser Engine Noise
~ Improves Sound effect
~ Improves Engine Torque
~ Improves Engine Responses
~ Improves Fuel Consumption
~ Improves Headlamp Brightness
~ Quicker and Easier Engine Start
My windows roll-up easier / quicker? Really? LMAO
 
#28 ·
#29 ·
It is quite possible that a HP gain does occur. More from refined power to the electronics than stable power providing direct HP. If this is the case (which I truly believe) then results will vary based upon the quality of your +12v power. Poor battery, alternator, bad contacts, bad ground can all have an adverse effect. I have seen a bad alternator cause a low voltage condition that caused the rear wiper blade to randomly turn on when the radio was turned on (mid 80's caravan). Bad power can do some crazy stuff. Good power makes things work they way they are designed. I'm not saying it is snake oil, it's not. Power filtering is something that manufacturers are not designing into modern day vehicles when they have some serious computing power and I can't understand why. Well, yes I can, I never really even thought about it until this thread, but from my experience, it makes total sense. I don't think it's worth $209, but I will verify that myself this weekend when I get home and install the cheapie. The last car that I heavily modded had to have the TPS slotted and adjusted just to get the correct voltage readings that the FSM stated. It too was plagued by bad ground problems.
 
#30 ·
So I received the cheapie unit from ebay. $15 and a total POS. I opened it up before doing anything and it's a complete joke. I am now pursuing step 2 which is building my own filter with a grounding bus. I have the plans and will be sourcing the parts throughout the week. It should be quite simple, power filtering is a easy process. I just wish that I had an oscilloscope to prove my theory. Remember, all I am after is noise free +12vDC noise free power and no spikes. I suspect that as in all electronics, good power equals good results form the sensors. Good results should equal accurate feedback to the ECM and proper engine management regardless of the tune.
 
#31 ·
Looking forward to your results and your potential for commercial production :thumbsup: depending on your positive results!
 
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