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Fishey 02-03-2009 08:17 AM

methanol Injection
I just did a search on the subject here in the 911/930 turbo section and really came up with nothing. I am currious on why people don't use a good methanol injection kit on there 930's to increase boost. I have used it on a few cars as a "hey we are cheap" solution or "hey I don't want to run race gas" but here on the 930 its got to be about the best solution I have seen for overcoming so many of the 930's downfalls. So is there a reason everyone and there mom isn't running it on there 930's that are moddified still running CIS?

Your Pal

purplehaze 02-03-2009 08:55 AM

Hey Fishey -

I've been wondering the same thing actually.

It's been discussed on several posts, and a few people have done it. I know of another 996TT who swears by it as it maintains their HP regardless of outside temperature. To me, it's sort of a no brainer - just another project.

In my opinion, I think it's because no big shop has undertaken the thing. I'll get flamed for this, but most folks tend to stay with the mods that everyone else did. I like pushing that envelope more and will likely go there within the year.

Craig 930 RS 02-03-2009 09:16 AM

I wouldn't squirt methanol into an uneven runner, dry manifold like the 930 has.
Uneven distribution + more boost may equal a cash outlay to repair damage. My opinion.

beepbeep 02-03-2009 09:20 AM

I believe it's much better solution to fill it up with E85 and lower control pressure untill AFR's are correct. 104 octane and lower EGT....

356-930 02-03-2009 10:07 AM

Water/Methanol injection works to raise effective octane of gasoline/fuel. The system I use (Snow Performance) claims effective octane can be raised from 91 to 116 by use of its water/meth injection system.
For 930 engines without an intercooler, water/meth acts to take its place. Intercooled engines benefit from water/meth by adding still more cooling.
Water/meth by itself does nothing to increase power. What it does is allow timing to be advanced which results in greater power.
Dyno results posted on Snow’s website (water cooled engines) show HP increase of 5-10% and torque increase of 10-15%.
Because the 930 engine cannot live with detonation, I do not recommend tuning it for max hp/torque by benefit of water/methanol but rather as added insurance against detonation. In other words, tune for max power without injecting water/meth, then “turn the system on.”
$600 to prevent a $6000 repair = cheap insurance.
To learn more, go to

Craig 930 RS 02-03-2009 10:10 AM

Where do you inject this stuff into - at what point (in the manifold) I assume?

purplehaze 02-03-2009 10:11 AM

I was HOPING you'd chime in, Chris! Thanks.

Nothing like real experience. And a beautifully unique install as well.

Cheers -

356-930 02-03-2009 10:19 AM


Originally Posted by Craig 930 RS (Post 4461695)
Where do you inject this stuff into - at what point (in the manifold) I assume?

Before the throttle plate, injector nozzle perpendicular to air flow. Pressure at nozzle is 150 psi and nozzle orifice is so small the water/meth is vaporized before being ingested into the manifold.

Craig 930 RS 02-03-2009 10:24 AM

That 930 manifold sucks so badly for air, I dunno.

356-930 02-03-2009 10:43 AM


Originally Posted by Craig 930 RS (Post 4461725)
That 930 manifold sucks so badly for air, I dunno.

Just one of the reasons not to tune for max power by use of water/meth injection. This said, no matter how bad the air/fuel distribution of the 930 manifold may be, whatever water/meth is injected will be equally poorly distributed with whatever air/fuel is being distributed.
It can't hurt anything if you don't add timing. It's added insurance via its cooling capacity.

Here's a bit of technical info that informs why adding water/meth to the air/gasoline equation will help:
By Klaus Allmendinger, VP of Engineering, Innovate Motorsports
Many people with turbochargers believe that they need to run at very rich mixtures. The theory is that the excess fuel cools the intake charge and therefore reduces the probability of knock. It does work in reducing knock, but not because of charge cooling. The following little article shows why.
First let’s look at the science. Specific heat is the amount of energy required to raise 1 kg of material by one degree K (Kelvin, same as Celsius but with 0 point at absolute zero). Different materials have different specific heats. The energy is measured in kJ or kilojoules:
Air ~ 1 kJ/( kg * deg K)
Gasoline 2.02 kJ/( kg * deg K)
Water 4.18 kJ/( kg * deg K)
Ethanol 2.43 kJ/( kg * deg K)
Methanol 2.51 kJ/( kg * deg K)
Fuel and other liquids also have what's called latent heat. This is the heat energy required to vaporize 1 kg of the liquid. The fuel in an internal combustion engine has to be vaporized and mixed thoroughly with the incoming air to produce power. Liquid gasoline does not burn. The energy to vaporize the fuel comes partially from the incoming air, cooling it. The latent heat energy required is actually much larger than the specific heat. That the energy comes from the incoming air can be easily seen on older carbureted cars, where frost can actually form on the intake manifold from the cooling of the charge.
The latent heat values of different liquids are shown here:
Gasoline 350 kJ/kg
Water 2256 kJ/kg
Ethanol 904 kJ/kg
Methanol 1109 kJ/kg
Most engines produce maximum power (with optimized ignition timing) at an air-fuel-ratio between 12 and 13. Let's assume the optimum is in the middle at 12.5. This means that for every kg of air, 0.08 kg of fuel is mixed in and vaporized. The vaporization of the fuel extracts 28 kJ of energy from the air charge. If the mixture has an air-fuel-ratio of 11 instead, the vaporization extracts 31.8 kJ instead. A difference of 3.8 kJ. Because air has a specific heat of about 1 kJ/kg*deg K, the air charge is only 3.8 C (or K) degrees cooler for the rich mixture compared to the optimum power mixture. This small difference has very little effect on knock or power output.
If instead of the richer mixture about 10% (by mass) of water would be injected in the intake charge (0.008 kg Water/kg air), the high latent heat of the water would cool the charge by 18 degrees, about 4 times the cooling effect of the richer mixture. The added fuel for the rich mixture can't burn because there is just not enough oxygen available. So it does not matter if fuel or water is added.

lucittm 02-03-2009 11:27 AM

I like my 911 Turbo just the way it is. It has more power than I can use 90% of the time. It is reliable. I don't have to order Boost Juice and wonder where to store it. I don't have to worry about spilling methanol on the paint or on me! I don't have to worry about what parts are being consumed by the methanol. I don't have to fill a little reservoir 2-3 times before I stop at the gas station. I don't have to spend $600 just because some guy found a way to market his product on the Internet.

I can't figure out one thing. The Snow website says their product prevents knock and reduces the chances of causing damage at high boost levels. Then it says that with adjustments to boost and timing, you can gain 30-60 HP. Doesn't that put you right back to the edge of the envelope of safety that you wanted to avoid in the first place?

Good engineering is a compromise between demonstrating your limits and limiting your demonstrations.
(yeah, I said that)

BoxxerSix 02-03-2009 09:17 PM

When using an injection system containing any amount of methanol you should always tune the motor for the methanol, not just add it in as an effective mask to detonation. No matter how much mixture is added, it always affects how the tune finalizes. With any of my tunes the injection fuel and timing maps are always far different than those not running injection. doesn't matter if it's 100cc/min water or 600cc/min methanol, although I prefer using an 80/20 methanol to water mix ratio for optimal results. Little bit of water actually helps steam clean the cylinders and keep carbon from forming, even on the Evo with the super rich 11.0-11.2 WOT trims......

Snow Performance is an ok system. They get certain parts from Labonte, which is another great system. I've used and installed both extensively(dealer for both actually), but prefer to tune with Labonte over Snow. Both companies offer boost or MAF reference based systems with a little bit of progressive tuning possible. I prefer Aqamist over all however their costs are often not justified on most vehicles.

I use Methanol injection on probably a good 90% of my customers builds. Evos, Subarus, Porsche, turbo diesel trucks, etc. I just love the benefits of using it on motors that are pushed 100-200% beyond their OE power capabilities in stock form.

Craig....I too believe that the 930 intake manifold is a problem with fluid injection. It's not meant to flow a fuel soaked airflow mixture without puddling and that would certainly result in a poorly balanced distribution. Typically if you're using a single nozzle system you'd want to inject the mixture into the charge flow before the TB, to allow it sufficient time to atomize and pull a little heat from the air right then. ~6-12" suffices most of the time, so that would put the nozzle right smack in the post- intercooler end tank on the 930/965's.

However with the 930 manifold in mind, I'd be more apt to run a multiport(multi nozzle setup) spraying directly down into the injector blocks from the manifold. What you have to watch for on post throttle setups is vacuum draw and creating a syphon, which could lead to fouling on deceleration, but worse would be hydrolocking the motor after it's been shut down. a simple anti-syphon solenoid(common upgrade in kits) is the key fix.

Craig 930 RS 02-03-2009 09:58 PM

If this is appropriate on a 930, then multiport sure would make the most sense.
Runner lengths sure vary on a 930....

Dynamohum 02-04-2009 09:25 AM


Originally Posted by purplehaze (Post 4461539)
Hey Fishey -

I've been wondering the same thing actually.

It's been discussed on several posts, and a few people have done it. I know of another 996TT who swears by it as it maintains their HP regardless of outside temperature. To me, it's sort of a no brainer - just another project.

In my opinion, I think it's because no big shop has undertaken the thing. I'll get flamed for this, but most folks tend to stay with the mods that everyone else did. I like pushing that envelope more and will likely go there within the year.

Hi, I've been wondering the same thing and I agree with what your saying.

This is a Great thread, I'm looking to Learn more before purchasing a W/A system.

930gt-40r 02-04-2009 09:27 AM

Individual injection is a must as Craig notes-
I am pretty sure the fastest 911 on the planet runs meth injection if that means anything.
I wouldnt try to go max performance without going multiport injection though. Meth-injection is proven and works well for EVERY other engine out there- Our motors are diffrent, but do opperate off the same principals of all other internal combustion engines.

Dynamohum 02-04-2009 09:41 AM

Great thread, subscribing to Learn more before purchasing a W/A system.

Please Not looking to get flamed here and correct me if I’m wrong.

The way I understand it: Providing your supplemental injection system (W/A) (Methanol) or whatever mixes your using is atomized properly directly in the main air stream. And given that no two cylinders are filling with air/fuel charge or firing at the exact same time. I speculate, that while operating with positive boost pressure as apposed to N/A (and while injecting as you would under load) that slight differences between your individual intake runners flow would have little if any measurable difference to the charge going into each individual cylinder. Well at least that's what I'm counting on for my 3.2 intake :)

Does Anyone have hard test data by Simultaneously measuring AF’s from each individual cylinder while injecting (correct rate of mix) to a motor on a dyno?

Here is a handy calculator you can play with

ace996 02-05-2009 08:48 PM

Water/Meth injection is a very good mod when used correctly...just like anything else. You can't slap a bigger turbo or engine management or injectors on a motor and run better/safer without doing it the right way. There are different uses for WI (water injection...I'll include meth injeciton, too) and different ways to employ it's benefits.

Using 15-20% of fueling requirements of WI, either 50/50 meth/water or 100% meth, will do wonderous things to your motor's power output...but it will need to be tuned (leaned and advanced timing) or it will probably run way too rich. With proper tuning, you'll find less lag...lower intake temps (meth/water cools air far beyond what intercoolers can do, even going under ambient sometimes)...lower tendency for detonation (water/meth is a very potent race-gas)...and will keep the combustion chamber quite clean.
It's quite frequent to hear of gains of up to 5-10% in rwhp and more in rwtq. I gained a good 40rwhp and 80rwtq on my Subaru STI after adding a meth/water injection system.
The best thing about that there is never heatsoak. The power I had on the first lap of Limerock was the power I had on the 20th lap of Limerock...the consistant power delivery and lack of heatsoaked detonation and power-fade more than made up for the added maintenance of filling the system (I had a 12liter tank mounted in my trunk, only filled it once per month on the street and refilled one-two times per trackday) which is very low compared to the benefits.

I often hear of 930 owners/tuners saying that the car is really limited to 350-400hp because of the fuel system? Well, I'd bet a proper WI system would fix that issue, and allow a much safer engine around the 400hp level. The new kits...Snow, Aquamist, Coolingmist...all have programable controllers that could probably work pretty well to augment a bolt-on 930.
And if the spray is injected just after the intercooler, the vapor would be well atomized by the time the uneven runners would enter the equation.

WI has not been embraced by the P-car world...and that's a real shame. It seems it's still seen as taboo by the old-school tuners, most likely due to inexperience with modern systems.

One day...

Be good,

Here's my STI's AFR/Boost graph...smoother AFRs with higher boost...

And my dyno graph...look at the gains in spool and torque down low!!!!...

Car ran like a beast...awesome.

DonE 02-06-2009 03:19 PM

I'm willing to give it a try. I sent you a PM.

Dynamohum 02-06-2009 05:33 PM

I'm interested also and sent you a pm

Fast951 02-06-2009 06:40 PM

I developed a WI system for the 951, I also experimented with WI on my type IV 914 supercharged engine. WI works, however unless you tune for it, you will actually lose power. Once tuned properly, addressing ignition and AFR, the results are respectable. As a example, on my 914 supercharged air cooled engine (converted to EFI running a Motronic system), I was able to increase the ignition timing anywhere from 8-10 degrees while under boost. This alone raised the power!

All this is nice and dandy, however there is a huge risk. Unless the WI + Engine management are working as a system, things can go wrong very fast. There are a few things that will cause a WI system not to operate properly or to fail. Unless you can catch and handle the fault, you can hurt the engine. This what most WI suppliers don't tell you.

Let's assume you advanced the timing 3-4 degrees (probably more), you raised boost by a few psi and leaned the mixture some (all over what is safe to run without WI). If any component in the WI system fails you mast capture it, be able to reverse to a fail safe state (lower boost, lower ignition, richen mixture back to a safe level). Some of the possible failure points on a WI system: power loss at pump, damaged pump, clogged nozzle, stuck solenoid, clogged filter, lost in line pressure are possible problems. Based on this information, you can imagine the complexity of a fail-safe system. If you track your car, the chances to recover from a error must be done without user intervention, there is no time act fast enough (electronics react much faster than me).

On a CIS engine, there are not many things that can be switched to fail-safe mode other than boost. So if you add WI safely you can just raise boost (as it's the only variable that can be controlled electronically). Not being able to alter ignition and AFRs, renders the use of WI a bit useless.
When using a multi-nozzle system, failure areas get a bit more involved. What happens if one nozzle clogs up? There is nothin on the market to detect this fault condition.

Ideally you want the engine in addition to monitoringthe WI system. If you have a Intake Air Temp in the intake and a EGT in the exhaust, monitoring both and triggering a alarm when things are not fine will be another layer to protect your engine.

A WI system on a 930 will be great. I plan on adding one once I'm done converting my 930 to EFI (using the Motronic, MAF & Wasted Spark). Both WI and Engine management will be integrated to handle the possible failures.

As a alternative for WI for the 930, a intercooler spray bar will help. Keeping the intercooler cold raises its efficiency and indirectly makes more power.

Lots of claims and marketing behind various WI systems on the market. Research every system! It's easy to design and sell a WI system. However designing a truly fail-safe system is not simple, and will cost a bit of $.

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