What's wrong with Voodoo?
 

I know I'm new here, and I know it's fun to say "omg search we've discussed this LITERALLY a gazillion times." but what exactly is wrong with the Voodoo system?

I've done plenty of reading on here, and I've done plenty of googling, and I"m sure there's fantastic information out there, unfortunately it is now buried under 5000 other threads of people calling it the "doodoo" box and saying 'You'll blow up your engine with that bandaid" and no real information at all that I can find..

I'm planning my first turbo build, and thinking I may go with the FM "no electronics" kit and then MS DIYPnP it, but what exactly is wrong with the voodoo kit, and what makes MS so much better?

Thanks for going easy on me.

Do you understand how a Voodoo Box works/doesn't work? That's really the key to the question. :)

It works on voodoo obviously, says so right in the name. wires come in, wires go out, and your fueling somehow ends up somewhat ok.

there's nothing inhernetly wrong with a voodoo system, especially the actual turbo parts.

Mea culpa, I am referring specifically to the engine management as that is the only part of this I am still "on the fence" about.

No timing control, only "extends pulse width" no precise fueling adjustments that you can get from a VE table.

Cole's notes.

Voodoo is limited by the size of your stock injectors, does not control timing, "tricks" the computer into supplying more fuel.

On that note, I thought timing was not adjustable on 99s? I have adjusted the timing of my 97,but I was under the impression it's not possible on a 99. Does ms change that?

MS changes everything. It's a game changer. Cures Irritable Bowel Syndrome.

On the 99's you just cant adjust the position of the timing trigger like you can with the NA CAS. You can do whatever you want to the timing once you have a stand alone.

Really. Damn, another reason to ditch the EMS4, I'll be able to eat salad again. :party:

This is the old style instructions, but Read what it is capable of: http://www.flyinmiata.com/support/in...Voodoo_Box.pdf

That said, Don't take advice from me... however what I can say is because my build is very simple and I don't really give a fk anymore (I'm older, not my first rodeo, this is a play car, getting another motor in isn't a problematic affair) I am choosing to rock the voodoo box in conjunction with a timing retarder because it's simple and in the mean time I don't plan on running higher boost. If it blows, then oops... 181k motor died and it's my fault. Ultimately, you live you learn. Don't necessarily reinvent the wheel on this one, but choose within your means. If you aren't comfortable with it's capabilities then save your money and buy the best if it's worth it to you, don't worry about what anyone else thinks... but do learn from everyone elses mistakes and logged experiences. If you plan on making good power and you're serious... do what the serious boys and girls do and spend the scrilla.

With forums everything outside experience is hearsay and reiterated bull caca, so listen to the dudes that have put in the work here.

Awesome, so it sounds like MS DIYPnP is the way I want to go.

What are the chances of me screwing the pooch on this one? If I miss a solder or something, there are tests and checks and such, and I'll know BEFORE I throw a rod, right? :-P

If you're worried about missing a solder, then maybe a straight up MSPNP is the way to go.

Unless you're really looking for the learning experience. :)

I'd just do a normal MSPNP if it were me, either from DIY or Reverent/MSLabs.

Why? Because i'm lazy.

Not particularly worried about that in particular, just curious exactly what would happen if it isn't exactly right. I've done some soldering and whatnot, and I'll for sure pick up a practice electronics kit first to tinker with and learn some more..

Mostly looking forward to the learning experience. :) and hoping I don't :vash2: my engine.

I'm going to hold your hand because I understand your pain. My knowledge may be a little out dated here, so bear with me.

There is nothing wrong with the rest of the voodoo kit, its just the voodoo piggyback card that we don't like.

The voodoo adds more fuel based on hardcoded assumptions like rate of airflow and injector size. Unless things have changed dramatically since I looked at it, the only feedback the voodoo sees is the tap on the factory narrowband o2 sensor and the boost line that runs to an on/off pressure switch inside the box. When the narrowband goes lean and the box sees boost, it hijacks the injector pulse signal and starts adding more fuel to compensate for the additional air provided by the turbo, based on RPM. It does this in a semi linear fashion, but its very clunky and not exactly optimized. More air needs more fuel. This seems OK thus far, right?

Well, the other critical part of the performance formula is timing. Too much timing makes a boosted engine go boom, and neither the OEM ECU or the voodoo does nothing to retard timing with boost. With earlier cars you have to retard the base timing and with later cars you have to use an offset timing wheel thus tricking the factory ECU into thinking "Hey, I'm throwing 30° of timing at the motor" when in reality is only running 20°. This kills the low end on the motor for the benefit of keeping things "somewhat safe" on the top end with the boost.

Boost makes heat. If the stock ECU sees a bunch of heat, it will pull timing to avoid detonation, so you are losing even more timing. "But that sounds good, you said too much timing kills boosted motors." Well, there is a point of diminishing returns: remove too much timing and you dump unburned fuel into your exhaust and you fry your turbo and your cat. Remember that voodoo card that's just kinda throwing more fuel on the fire? Yeah, that's an issue. "Well, I'll just run an intercooler then. This will give me a denser air charge and drop my IATs so the stock ECU won't pull as much timing."

Congratulations, you have now built a totally unpredictable system with a myriad of variables controlled by 2 separate devices that have no inputs to compensate for the above listed variables. The Voodoo Card is a series of compromises that runs on a lot of assumptions, compromises and tricks. It gets the job done~ish, but its rather crude and has very little room for expansion or modification beyond the initial design envelope, and has little to no optimization.

Will the voodoo keep your engine together? Probably.

Will you pick up 20-30hp, 5-10mpg and better throttle/boost response on that same exact build if you swap the voodoo with a Megasquirt, a wideband and proper tune? Absolutely.

If anyone sees anything wrong with the above info, feel free to call me out on it so we can all get edumicated. :bigtu:

I believe you build yourself a jim stim that will allow you to bench test the MS before installing it.

This makes perfect sense, and is exactly the information I was looking for. Thank you so much.

Is that why your username is "Leafy"?

So, if I *am* planning to go with MS, are there any other kits out there that are as complete as the FM kit, but for less? I was looking at some of the begi kits, but it's hard to tell what all "extra stuff" i would need.. Is (for example) the Begi-S a "bolt on" kit in that it includes everything needed other than engine management?

I have a 99 base, and I really think I'd be happy with 180-200whp. I had a GTI and 200hp in that was more than enough for me, and this car is quite a bit lighter.