doo0T!doo0T!

I recently got my supercharged B18c running again after a full rebuild and forging and got it on to the dyno to try out the water-meth injection system only to find it was a big old FAIL.

I actually lost power no matter what we did with fuel and timing or water:meth mixture ratio or pressure.

I went for an individual port injection setup rather than an upstream fogger and although it probably cools the actual combustion temperature a lot it doesn't allow me to use it to make more power. Knock was reduced but even by adding more timing we couldn't make more power.
I seem to be just wasting power in converting the water to steam.

Here's my current set-up:

JRSC kit
3.8" snout pulley
6.5" crank pulley from JDM b20b
Ported blower and manifolds, S-pipe etc
ITR head and cams
Forged 10:1 compression B18c block.

Power: 160wkw no water, 155wkw with water at 13psi peak


We know the water was cooling things internally as it reduced knock and EGT dropped.

The main problems we think are:

1. Water injectors are downstream from the IAT sensor so even though they are squirting water the Hondata still thinks the IAT is getting out of control. (over 6000 at wot IAT approaches 210 F / 95 C)

2. There is no cooling effect by the water on the blower it'self so while the cylinders are protected the blower is still very badly effected by heat sinking.

3. High IAT readings means the ECU pulls fuel out because hot air is less dense and has therefore less oxygen in it. Less fuel and less oxygen means less power and no amount of fuel correction or ignition correction will magically make more power if there is simply not enough oxygen.

Where does everyone else here injecting water put their injector(s)? and if you use one single injector what cc rating or hole diameter is it?
I don't want to spray into the plenum above the SC as there's too much risk of it not getting evenly distributed between the cylinders. And there's next to no room.
I'm nervous about spraying up stream of the blower because of water droplets hitting the rotors at high rpm.

Should I not be bothered by this?

I want to block off the individual port injectors and go for one big sucker straight into the S-pipe.
This should cool the blower and also cool the air which the IAT reads meaning the ecu wont pull as much fuel.

Heres a few pics of my setup:

4ltr tank.
Bleedback valve to de-pressurise when turned off.
Pressure gauge.
600ml 10 bar pressure tank for smooth fluid delivery and to get rid of the hydraulic hammering/pulsing from the pump.
Cooling Mist Sure-flo auto cut-off pump, currently set to 100psi shut-off.
4x90cc injector nozzles.
4 port manifold rail.
Activation solenoid
Low water level float switch.
Controlled by Hondata S300







Any help or advice woudl be much appreciated, and please do not turn this into a LHT vs water/meth discussion!

Tony the Tiger

Direct port setups are always a fail IMO most of the time; before the water/meth can atomize properly and soak the heat up from its surroundings, it has already entered the engine in huge clumps and killing power and efficiency.

Direct port setups do work on high boost high power setups; with the high boost and really high charged air velocities, the process happens fast enough. Even that though, I have experimented with many setups and a single big jet, sprayed at a moment which the engine needs it, is by far the best method.

For a JRSC, your best bet is to run a single nozzle before the supercharger, and let the water/meth cool the rotors and allow it to really distribute the water evenly. Cobra guys have been doing it for years, and I have done the same for my SOHC D16 for close to 120k miles. The supercharger has no problems dealing with a light mist of water, and the heat expansion and contraction is no different than you driving your car through a humid and foggy night. If the car is tuned for it, all your IAT compensations will be properly dialed in as well.

Lastly, spraying a combined 360cc/min of water flow from all four of your jets (assuming it's over 45 PSI at the jet) is a lot of water/meth. For your power level, I would go with a total of 150-175cc at the very most if you want to realize gains from cooling and not have to go stupid aggressive on the tune.

doo0T!doo0T!

Awesome thanks heaps for that insight Tony, good to hear it from someone who has experience.
Yes I suspected we were spraying too much meth as at 150psi we were actually putting the spark/combustion out entirely and getting an intermittent miss even at 6K+
It wasn't till we wound the pressure back to 100psi that the miss went away but man the smell of meth was still strong in the exhaust, stank out the dyno room.

I'll try what you have suggested and drop to a 175cc jet and use the pre-tapped hole in the S-pipe just infront of the charger, the one that's usually used for a PCV tube.

The only reason I went with 4x90cc injectors is that's what cooling mist recommended for me.

JDMCRX

iTrader: (2)

Well the setup you have like stated has a bit of a hard time attomizing prefectly being so short a runner. Run either a single nozzle in behind the throtle body or run the 5th injector behind the throtle body.

Or get a LHT intercooler set up

doo0T!doo0T!

For the price of an LHT from here in NZ I might as well pay an engineering company to build me an intercooled manifold from scratch.

Lets hope I don't have to, this meth thing is bound to work ok once it's set up correctly.

I've seen those inline cores on ebay though at $50 each and I must admit it's got me more than a little tempted.



Fingers crossed the water/meth works, I just want to get this thing working reliably and making reasonable power so I can sell it and start another project.

Pumpking.

i have done many different meth setups.

single nozzle. m5
dual nozzle. 1 in cold side. 1 in IC endtank. 2 m5 nozzles.
direct port. 4 m3 nozzles.
back to single nozzle. 1 m10. in cold side.
single nozzle. m14. in coldside.

all on 150psi pump.

NOW:
250psi pump w/ m14 nozzle (effectively like an m20) in fmic end tank


direct port was a waste of my money. after spending 2 2hr sessions street tuning w/ no prevail, i took it off, and sold it.

Jaker

Keep talking guys. I just bought an AEM kit, and will be implementing it with my M62 Endyn D series kit. I was contemplating doing it with port injecion, but it sounds like that would be a mistake. I will be activating it with the AEM control box, but I'll also install a liquid solenoid to stop the vacuum from sucking all the liquid out of the reservoir when I'm in vacuum. The nozzle will be between the TB and the blower. The solenoid will be opened by my S300 when it sees 5 psi of boost, and then the AEM stuff will take over flow control starting at about 7 psi. The setup is expected to run upwards of 18psi of boost, hence the need for some sort of cooling. There's absolutely no room for any sort of intercooler cores in the manifold.

integrawow

Must inject before the supercharger. Blowers always have a funny way of either actually icing up or nearly icing up when it can draw in and speed up the flow of methanol mixed air. All it's really doing is replicating the venturi effect, but only several times over since there is methanol involved versus gasoline and moisture. Ever watch a top alcohol funny car or dragster? You ever see that can of DE-ICER they are spraying on the butterflies? It's to keep the butterflies from icing up since they are injecting methanol into the supercharger. That, along with a little humidity, and you have an injector scoop that is colder than ice.

Yeah, if your blowers' rotors can handle the addition of a higher concentration of methanol mix, then inject a small amount pre-blower. You shouldn't need much, but who knows, it may want more and more. Get the damned thing aimed right. You don't need puddling before the blower. It will either get the supercharger ice cold and make more power, or ....well, actually I couldn't imagine it not working. I can imagine what you have not working since you're almost injecting it right there at the tops of the runners, which doesn't allow the methanol to have any kind of a "somewhat venturi effect."

Hopefully this helps.

JDMCRX

iTrader: (2)

Im still debating on how i am going to inject mine. Im not sure if the laminova's will like the methonal.

Ill more then likely spray before the TB and it will have a better chance of atomizing being further away and will help cool the rotor blades off and also have one at the back of the intake manifold to spray inside the intake manifold

Pumpking.

im not exactly SC literate. but if no intercooler, maybe try 2 nozzles, and increase your water content slightly when doing so. i also tend to toss my meth/water mix in the freezer the night before i know i am racing. 25* liquid being injected sure as hell makes a big difference compared to room temperature (70-75*)!

id also venture to say, if you are trying to make the meth kit as efficient as possible...weld in a 45* 1/8" NPT bung on your pipe b4 the throttle body.

ive tested many different locations...and you would be amazed at the significant improvements/gains of spraying it either parallel into your system (ie into your coldside fmic tank, shooting straight into your coldside outlet) or as close as possible to parallel via a 45* angle.

this is all in comparison to the typical setup where its tapped directly into your pipe making the meth hit the inner wall of the other side of the pipe, causing puddling and loss of atomization.


hope this helps.

Pumpking.

dont. you will have a non-equal meth dist. if you "tap a nozzle into the middle backside of your IM".


well, if you do, make sure you log timing and knock in each cyl and lmk if you see any variance.

Jaker

I will easily be able to mount my nozzle a good distance from the blower, as my TB is relocated with this kit. A bung welded in a good 10" from the blower, spraying upstream at 45 degrees should do the trick.

doo0T!doo0T!

Yeah I've read about mounting the nozzle at 45degrees spraying against the airflow having a much better atomization effect.

Heres the next question then.

Who's for spraying before the TB and who is for spraying after.

Bare in mind I'm talking about a supercharged car here which doesn't pressurize before the throttle body like a turbo does. I dont know if that makes a difference or not.

Integrawow, I know what you are meaning, I've seen carbs icing up before too, it's basically because during the draw-in the air is being slightly de-compressed due to the vacuum combined with a wind chill factor when there's enough moisture in the air for it to conduct.
When you decompress something it absorbs heat energy therefore cooling all the parts around it.
Just like when you open a propane bottle it will ice up the valve.

However I'm not sure that we can compare a top fuel alcohol blower on a chevy donovan to a little M62 on a honda.
They get so damned hot you could cook eggs on them and the heat from the blower quickly conducts all the way out to the TB.

If there is any decompression cooling present at the TB then do we want to be spraying meth into it behind the TB or in front so the meth is drawn through and decompressed as well?

Bare in mind that the top fuel guys don't squirt before the butterflies, they squirt after.
The bug catcher on top of a V8 supercharger is essentially the throttle body we have on our hondas.



****edit...

Jaker, that endyn kit has a much better S-pipe design than the Jackson one, there would be heaps more room to inject without hitting a wall and puddling.
The S-pipe on the jackson is quite oval so if injecting from above or below the opposite wall is very close.
For this reason I'm hesitant to spray into the S-pipe.

integrawow

Inject after the throttle body, and directly before the blower.

Yes, you can compare to a top alcohol blower setup since it's still a blower, and the same physics are involved. In a top alcohol motor, there is an injector plate stacked on top of the blower, and methanol is injected straight into the blower. They don't inject before the throttle blades.

Arcane

Correct me if I'm wrong but I believe the IDEAL nozzle position on a S/C setup is right before the blower. However, most people the nozzle further away, pre-TB to prevent the vacuum from draining their water/meth tank.

integrawow

One could probably use a fuel solenoid for that. The same ones used in a nitrous kit. When the methanol injection system is activated, then so will the fuel solenoid be activated. A filter would more than likely be needded as well to protect the solenoid. Just make sure the particular fuel solenoid being used can withstand the amount of methanol pressure being injected.