Good point. That's one of the reasons i liek the kit AEM puts out. You dial in your "minimum boost" and "maximum boost". So it starts spraying mildly at the low boost setting, and progressively ramps up untill the max boost setting is reached.

 

I hear ya. The 7th injector was just part of the kit. I think it was more to offset running lean and to keep the buyer from having to get a tune (plug and play kit, cut down cost, etc.) It only cuts on at WOT.

I'm with you though. I'd think the 7th injector/meth mix would be somewhat beneficial.

 

Good point.

 

With regard to the more aggressive tune, the OP stated that he did not want to re-tune.

Bad tank of gas... I can see that, it sometimes happens, but the stock ECU will pull back timing when knock occurs, as will many aftermarket EMS's (the HKS AFK handles that for me). If the OP is not using the stock ECU nor an EMS or other device to handle knock, then it is a valid point. If he has knock protection, well, injection is nice but not absolutely necessary. Part of this also comes down to how much safety margin he has in his tune.

Heat soak... makes sense if the injector is placed before the S/C and the OP is pushing it hard enough for that to become an issue. For that specific issue, injecting straight water before the S/C seems like the optimum choice. I've not heard of S/C heat soak being a significant issue on the relatively small S/C's used on our cars, but then I'm a TT guy and I haven't followed all the S/C threads, so it could be an issue, but likely not with the OP's S/C. But who knows...

OP, have you had any issues contributed to heat soak, or that you might think are contributed to heat soak? In other words, does your performance degrade after pushing it hard, or is it pretty consistent for a given air temperature?


MethTech, do you have any data you can share with the forum?

Please don't make me beg.

In all seriousness, we have been discussing the issue of meth/water injection for a long time now, and many of us are using injection, but as I noted the only data we have is the NACA report and the experiences which have been shared with us verbally. It would greatly appreciated if you can share with us any data that you have concerning this subject!!!!!!!!

We know straight water, straight meth, and a water/meth mix are all beneficial. Any data that you have showing a comparison of these would be helpful, especially if it shows those differences at intake air temps closer to those at which we are operating, figure in the 80 deg. F - 120 deg. F range.

 

let me make it short and sweet... is it worth it? NO!!!!!!!!!!!!!!!

 

That's my perspective, especially considering the OP does not want to pay for a re-tune...

 

It runs consistant boost/performance/and AF for the given seasonal tempratures. I.E. I feel little performance gains in the Summer, enjoyable performance gains in the fall/winter months.

I'd just like to add some extra cooling across the board, since cool dense air>hot dry air. But i think you go the gist of the extent i'm willing to go to get there. I'm not trying to be cheap, as much as it is that i'm aware that even dumping a substantial amount of money into what i already have will yield me little to no safe gains. You can really only spin this tiny blower so fast. At some point it became a superheated air pump, and risk wearing the lobes down due to expansion. And i'm already on the verge of that now.

So i figure why not just polish a turd a bit by working with what i have!!!


FYI, i've never measured my post charge temps, but i'd image they are considerably higher then 80-120F just given the nature of how the roots blower produces it's boost.

 

Thank's for biting your tounge on this one doug. I know you are dying to throw out your two cents in reguards to this setup. LOL

 

This would indicate that heat soak is not an issue.

A meth/water injection system should allow you to advance the timing a bit with a re-tune, which will help give you a bit more hp. Considering the cost of the water/meth injection system and a re-tune, this is not something I would pursue with your particular setup. I just don't think it is cost effective.

If you really want a significant performance increase, I would save your penines, get a built short block, and add a turbo system. You already have a roots type supercharger, so you could even try a twin-charged system if you are fealing adventurous. Another option if Nitrous, just be sure to change your oil often and every time after significant use. If you have questions regarding Nitrous, go to that section of the forum. Any questions you have regarding this can be answered using the search feature.

It's your car, your build, and your money. If you want to give a water/meth injection system a try on your current setup, no harm done assuming you run straight water. If you want to run meth or a meth/water mixture, my suggestion is that you get a re-tune. Period.

 

I'm with ya. I'll probably leave it how it is, or keep my eye out on ebay and pick up a used set up to mess with. I don't drive my Z enough to justify building up the motor, etc. so i'll just enjoy what i have!

Thanks for all the help!

 

^ dont even mess with a used setup. the 150psi shurflo pump is $85. nozzles are 4$ and check valves are cheap from mcmaster carr. Hobbs switch is like 10$ and you can get the hoses and fittings from Home depot.

or this guys has everything for way cheap as well
http://www.aquastealth.com/waterinjection.aspx

 

Cmon Dougie you no you love this kit.I do think that this would help the stillen but you would def need to get rid of the ss box and at least get the utec and a tune.The stillen as i remember sucked in the heat of summer but really did a whole lot better in the cooler months......i think it would be a good thing with a retune and without the ss box.

 

you're choosing to move forward.. thats all that matters

 

Good stuff, thanks!!

 

Truth be told I dont have a ton of data on a Stillen system. We are a small 6 person company, though many seem to think we are some sort of huge firm . We get our data from the feild from impartial 3rd parties in most cases, mostly for credibilities sake.

The thing is, as I understand it we have about 3 options suggested in this thread:

1) A new setup entirely. May well be the real solution considering how power 'needs' tend to climb.
2) Doing nothing. Yech.
3) Injection, with or without a re-tune.

The fact that the OP feels some gains in the cooler months does indicate that heat is a factor, though how much is certanly hard to determine considering we do not have IAT data for this particular car. And we all know that the amount of pressure and flow his current setup can provide is pretty limited.

Now putting in our system without a re-tune is definitely leaving benefits on the table. But frankly getting any gains with any suggestions mentioned so far requires a tune anyway if it's to be done right.

If the obstacle to running more boost (and hopefully more airflow as a result) is the excessive heat it will produce from the small Stillen unit, then injection addresses that very well. If the obstacle is the detonation caused by that heat, again, injection handles that well too.

I dont want to write a novel, but the basic idea I am trying to get accross about this technology is that it directly addresses the issues that tend to crop up in setups like this when more power is desired. The fact that it does this for under 500 bucks in a DDable setup that is easy to install and eliminates the need for race gas makes it a pretty good option IMHO.

 

^^^^

Without a re-tune, how much power do you think he will pick up with your kit? Remember, it is a relatively small SC, and heat soak does not appear to be an issue.

In my experience, when you drop the AFR below around about 12.5 or so, you actually start to lose power. So that takes meth out of the equation unless he is currently tuned for an AFR above that at peak hp, which is not likely.

Now, you will get some cooling with water, which may help make the air a little more dense, but he already has an intercooler, so how much is it really going to help?

 

I don't think he is asking for peace of mind or added saftey.. he said he is bored with his setup and he wants more power.. so why is he going to spend $500 to add more added security when its not addressing his core problem..

 

You got it! Basicaly i'm trying to make the most of what i have now. And if i can run more efficient and consistantly throughout the year (mainly the hotter months) for a few hunder bucks, then that's worth it to me. If i have to spend a few hundred bucks for the injection kit AND get a Utec AND a tune, only to squeeze maybe another 20 HP out, then that's not worth it to me IMO. My setup runs as designed now using the Stillen piggyback ecu.

For thsoe that may not be aware, this setup uses a Stillen provided piggyback ECU to "intercept" specific signals before they reach the factory PCU. This unit can't be easily tuned.

 

The consistency will be there even without a tune due to the cooling, but for the power a re-tune is key. In this case it really does sound this is not quite right for you at this point due to that fact that you cant fully take advantage of the benfits.

Honestly, if I was trying for the extra edge and I really did not want to tear into the powertrain, I would look at weight savings. Then too, I am insane and comtemplate things like diesel Miatas and such

Now when you slap a 35R on there.......

 

The whole benefit to water/meth injection is to lower IAT which will let the EMS run a more agressive timing map. That said the stillen by it's design is **** poor at cooling the air charge AND the throttle body is before the compressor so there is no easy way of telling the EMS what the air temps are to properly map the timing.

If you really wanted to get a serious boost you could fashion a system like they had on the Ford F150 Lightning. You would need to have 2 charge air cooling systems, one being the primary and a secondary system that is plummed thru a heat exchanger that is also tied into the A/C system. When properly setup it would give a brief maybe 20 second burst of chilled water to the intercooler.

Water to air are just not as efficient as air to air charge coolers. The reality is be happy with what you get from the stillen or replace it with a centrifugal system or turbos.