Dale's meth injection fun - pre vs. post TB and dual vs. single nozzle

[dale_gribble]

Quick backstory. I've been running 50/50 water/methanol injection for almost 3 years. It is pretty much an imperative in San Diego, living at sea level with poor quality premium gas. I started with a Devils Own DVC-30 system, and the system has evolved over time to it's current state which is a Cooling Mist CMGS system + failsafe box. I like the Cooling Mist controller more because, 1) it has a failsafe which reliabily monitors pump current and 2) it has a nice gauge with good status readout. I am still using the Devil's Own Pump, nozzles and holders.

I had an idea that post throttle body methanol injection might provide a slight improvement over pre throttle body methanol injection. I was unfortunately wrong. I moved my D07 nozzle from the TB inlet pipe to the Damond throttle plate (as seen below). Same nozzle, same tune, nothing changed. I had a strong base map that has yielded consistent performance with 0 kr for weeks before the change.



After moving the methanol nozzle behind the TB, I saw consistent KR run to run from 5k-6k where there wasn't any KR before.

Here you can see that even though BATs were lower, the post TB D07 caused kr.



Below is a confirmation that the runs were on the same tune. Same Ign Adv. curve, same MAF, same AFRs (until KR).



I moved the D07 back in front of the throttle body and the KR went away back to my baseline. That's not to say that the throttle plate nozzle adapters aren't a good idea, but I would have had to dial the tune back probably 1-2 degrees and maybe a psi to tamp the KR down, which is still better than pump gas but not as good as pre TB. So, honestly, if you are installing a meth system, PRE TB is probably the way to go.

[dale_gribble]

For my next experiment, since I determined that pre TB meth injection was the way to go, I played with single larger nozzle vs. dual smaller nozzles. This was pretty interesting.

Slayer at VWVortex did a great job characterizing different meth nozzles at 200-250psi. This was his findings (and link to his thread which is great).



VWVortex.com - Nozzle flow test results

Based on his data, my single D07 setup flows 655ML/min @ 200psi. My dual D03 setup flows 580ML/min @ 200psi. So, the D07 should outflow the dual D03s. I first made a dual nozzle pre-tb setup for the car. I'm having my regular pipe made with bungs to get the nozzles flush with the pipe ID, but for my testing I used a piece of 3" steel pipe and drilled/tapped for nozzles for testing.



Here's a bench test of dual D03s, offset about 90 degrees and 3 inches vs. a single D07. Mostly, the flow looks pretty even.

https://youtu.be/EslQrhEAt0Q

However, on the car, the dual D03s had a larger impact on AFRs and actually knocked AFRs down more than the D07. You can see where the AFRs go much richer on spool up and then rich again towards redline.



So, even though the D03s collectively flow LESS, they must be mixing better with the air and getting more concentrated up to the combustion chamber. I will need to dial in performance if I decide to run the dual D03s. I'm still deciding what to do there.

[blackms3_71]

Wow based on that graph, my d10 can flow!! I dont see numbers for above 200 as i run 250 psi but i bet its even more improved. Very good findings btw. Keep it up.

[dale_gribble]

I think the D07 is the max size you can install without impacting AFRs much. Once you go above that nozzle size, you definitely need to tune it in (although you probably know that).

[jdmage_mx5]

Guess Ill stick to both worlds; meth after throttle plate and two 1000cc fuel injectors pre plate LOL

As always Dale, thank you for your attention to detail and ability to remember to keep statistics in order.

[doctavus]

Man I bet that car is a hoot to haul ass from a dig and roll.

[blackms3_71]

Originally Posted by dale_gribble I think the D07 is the max size you can install without impacting AFRs much. Once you go above that nozzle size, you definitely need to tune it in (although you probably know that).

Yes. On this point that is true. D10 does effect afrs by a lot lol.

[sheston]

Can you put some data to the argument about how far you want to be from the throttle body? If pre-throttle is better, how pre is best?

Good stuff. Always good to see back to back testing.

Why do you think with the 2 X D03s having better atomization, the D07 looks to have made better power?

[blackms3_71]

Originally Posted by sheston Can you put some data to the argument about how far you want to be from the throttle body? If pre-throttle is better, how pre is best? Good stuff. Always good to see back to back testing. Why do you think with the 2 X D03s having better atomization, the D07 looks to have made better power?

I always heard about a foot or less. My set up i believe i am about 4 inches from the tb as i have my nozzle in my coupler.

[neganox]

Any thoughts on the reason for the KR to occur while utilizing the TB plate? I have inconsistent KR occurring at the same points as well.

[dale_gribble]

Originally Posted by sheston Can you put some data to the argument about how far you want to be from the throttle body? If pre-throttle is better, how pre is best? Good stuff. Always good to see back to back testing. Why do you think with the 2 X D03s having better atomization, the D07 looks to have made better power?

Because the D03s fattened up and richened AFRs (not to mention it's still 50/50 mix), I would have to actually lean AFRs a bit to compensate to dial the power back in. Probably too much water at that point too.

Originally Posted by neganox Any thoughts on the reason for the KR to occur while utilizing the TB plate? I have inconsistent KR occurring at the same points as well.

My tune was running clean and was dialed up just below knock threshold. So, for whatever reason, the throttle plate location must not mix as well in one or more cylinders. I suspect cylinder #4 isn't getting mixed too well, but that's just a hunch, because I did see lower BATs with the throttle plate adapter, meaning the MAP sensor that reads BATs was probably seeing more meth at the sensor.

There's no reason that the throttle plate would cause KR. It's just in my case that I was tuned above what the plate can deliver. If I dialed down 1-2 deg spark adv and or a little boost, I'm sure it would go clean again. For you, maybe just dial the tune back a bit and see if it goes away. If you detune and it doesn't go away, maybe it's getting some false kr i.e. mechanical noise.

[MD1032]

Very interesting data. Thanks a lot, dale. I have a throttle body spacer I had planned to use with my methanol setup whenever I install it, but perhaps based on your data, it would be best for me to simply tap the factory "cold" pipe coming off the intercooler instead and resell the spacer. I'll be running a single D10 nozzle to start with, but maybe I'll go ahead and tap a second bung in case I want to experiment with dual nozzles like you have.

edit: Also, when I had looked up the specs on the D10, I noted it was rated for 800 cc/min (mL/min). It's funny that it's actually over 1000 in slayer's testing. That means it will actually be above the range of the AEM failsafe/flow gauge I bought.

[dale_gribble]

Yes, nozzles' flow rate are usually specd at 150psi yet even though pumps are set 200-250psi. That's where the extra flow rate comes from.

[Yatta]

I would be interested in looking at AFR’s on a per cylinder basis, I would guess (and that is all) that the further upstream from the TB you are the more consistent the loading is per cylinder, the closer you are to the cylinders the more chance you have at getting more or less per..... I am about to install (had it for almost a year, doh) a DVC-30 and the question I have had is pre or post IC... (I am still TMIC) I am not only after the obvious anti-knock/cooling benefits but also the cleaning benefits (I am still EGR and PCV, I think for a road car they serve an important purpose).... my configuration considerations are currently a) d07 in the 2006 MS6 cold pipe... b) d07 pre IC, c) d03 cold pipe and d03 pre ic.... great post btw, thanks!

[dale_gribble]

Everything will tell you if you read that pre IC is not good. The mixture will bounce against the cooling fins and the WM will just collect there in the IC. One of our tuners ran an experiment and it was inconclusive. Post IC, pre TB. I had a nozzle bung welded into my 06 cold pipe and it turned out fine.

[neganox]

Now you'll have to do dual nozzles one pre TB and one post TB w/ the plate. You know you want to. For science!

[dale_gribble]

I must be moving on to my next project meow which is going to be fun.

[dale_gribble]

I was watching the video some more (https://youtu.be/EslQrhEAt0Q), and I noticed that the output cones out of the D03s are more even out of the nozzle whereas the D07 output cone is more concentrated out of the nozzle until it starts finely misting. Perhaps that is why the D03s mix better and impact AFRs more. The boost air is going to grab and mix more evenly with the D03's cone output, whereas the boost air might not mix as evenly with the D07 cone right out of the D07. To prove this, one would have to pressurize a tube to 20-25psi and see how the airflow grabs and mixes with the water/meth mixture.

In addition, you can see why you want the nozzles at a minimum flushed with the pipe ID if not slightly recessed. When the nozzles are inside the pipe, there is a section of pipe volume where air won't mix with the wmi. You basically want the output cone to fill up as much of the pipe volume as possible for best mixing while still not having the cone clipped by the pipe or bung.

Also, since we're on the topic of WMI, please read my failsafe misadventures with the AEM WMI 'failsafe' kit if you are interested. After replacing 4 flow sensors, I just gave up on their setup. I suspect that the flow sensors can't take the abuse of the pulsing pump output and/or methanol even though they are supposedly made for it. The Snow kit uses the same flow sensor, its a GEMS FT-210. This is also why I went with the cooling mist CMGS and FSB that monitors pump current.

How to integrate the Guardian Angel with a WMI Failsafe

[chaser27]

good info @dale_gribble; I suspect the KR with the TB plate is due to uneven mixing to each cylinder. Also interesting to see the non-atomized spray when you first turn on the D07. Are you using check valves? how close to the nozzle?
@Yatta; meth can actually cool the charge air below ambient, so if you spray pre-IC, you could potentially be heating up your air in your IC. This is why people really only spray pre-Turbo if they are spraying anywhere before the IC.

[dale_gribble]

Originally Posted by chaser27 good info @dale_gribble; I suspect the KR with the TB plate is due to uneven mixing to each cylinder. Also interesting to see the non-atomized spray when you first turn on the D07. Are you using check valves? how close to the nozzle? @Yatta; meth can actually cool the charge air below ambient, so if you spray pre-IC, you could potentially be heating up your air in your IC. This is why people really only spray pre-Turbo if they are spraying anywhere before the IC.

Ya, using an upgraded check valve from alcoholinjectionsystems.com. There's about a 5-7" run from that to the nozzle holder. It pees a little when the pump is off but no biggie. It probably wouldn't hurt to shorten up the run a bit.

[dale_gribble]

I just picked up my permanent pre TB 3" meth pipe from welder this AM. Two meth nozzle bungs welded onto a 3" pipe, decked to the right height so the nozzle is just about flush with the ID of the pipe. The bungs are about 3" apart and offset by 90 degrees. I think I'll probably swap the D03's back in and try tuning it in. Its mixing better with the boost air vs. d07, so I just need to spend the time and dial the delivery curve in. I'll also move the check valves right before the nozzle holders also.

[blackms3_71]

I kinda wanna do this with my d10 and run two d5 or something. But i am only on ko4

[sheston]

Don't let the K04 stop you, I was running a D03 and a D07 at one time. On a K04 :-)

[dale_gribble]

Ok, my final dual nozzle setup is installed with dual D03s. I really like how it turned out. FYI, if you are ever aligning pipe and silicone couplers that are a tight fit, use a little water based Trojan lube. Works like a boss. I'm going to start playing with the meth injection curve to make sure the setup doesn't run too fat.

I usually had it on around 12psi and full around 21-22psi. With the dual D03s, I'm going to have it come on around 15-17 and full around 25-27. It won't hit 100% duty cycle this way since my tune maxes around 23psi.

[AwAfrican]

@dale_gribble; you make me want meth

Sent via tapafail.

[MS3Shadow]

Originally Posted by AwAfrican @dale_gribble; you make me want meth Sent via tapafail.

Give in to the meth.


sent from my Nexus 6P

[AwAfrican]

Originally Posted by MS3Shadow Give in to the meth. sent from my Nexus 6P

I wants it

Sent via tapafail.

[dale_gribble]

I've been running it so long now I don't even really think about it. It's just like adding washer fluid.

[riflex]

great information, looking forward to your findings

[Stryker125]

Great info as usual, dale. Unless I missed it, is there any reason why you didn't try running the dual d03 nozzles post TB? Maybe a little redundant at that point?

[Vader]

Good info here.

I've been running dual D05s for about 2 years now.

Aside from the obvious data, 2 small nozzles will usually be better than 1 large, simply for the fact that they atomize better.

As usual, another fine thread from you Dale.

[aviator79]

I want meth but I am too lazy to keep meth tank full.
Good info. Saving money flowing less.

[dale_gribble]

Originally Posted by Stryker125 Great info as usual, dale. Unless I missed it, is there any reason why you didn't try running the dual d03 nozzles post TB? Maybe a little redundant at that point?

I ran a 1:1 comparison with the same nozzle pre/post tb and saw that kr pop up post tb which told me the air and meth probably isn't mixing as well/evenly. So, I don't see a reason to try and doctor a less efficient nozzle placement, not to mention what a pita it is to swap the post tb nozzles. Pre tb I can swap a nozzle in 3 minutes. Post tb, you have to pull tb and all the connecting stuff so that's an easy half hour to hour round trip. Nah.

[alexwlwsn]

Awesome write-up man, thanks. I'm running a single DO10 at the moment in a TB spacer and you're making me want to try double 5s pre TB.

It seems like the results were dramatic enough to spend a little time and money on it.

[aviator79]

I would assume the venturi the TB creates helps mix along with transition from HP to LP as it passes thru TB. The freeze cap nozzle mount did not work well either, thou it was not even in the flow like post TB spacer.
2 nozzles in the spacer may very well work better but I would still worry about even mixing to each cylinder. 6 DO1s should work.

[blackms3_71]

Originally Posted by aviator79 I would assume the venturi the TB creates helps mix along with transition from HP to LP as it passes thru TB. The freeze cap nozzle mount did not work well either, thou it was not even in the flow like post TB spacer. 2 nozzles in the spacer may very well work better but I would still worry about even mixing to each cylinder. 6 DO1s should work.

Yolo

Originally Posted by alexwlwsn Awesome write-up man, thanks. I'm running a single DO10 at the moment in a TB spacer and you're making me want to try double 5s pre TB. It seems like the results were dramatic enough to spend a little time and money on it.

Thought about the same. I run a d10 too.

[neganox]

Originally Posted by dale_gribble Post tb, you have to pull tb and all the connecting stuff so that's an easy half hour to hour round trip. Nah.

You love dropping and lining up gaskets. Admit it.

[sheston]

Originally Posted by dale_gribble I've been running it so long now I don't even really think about it. It's just like adding washer fluid.

You either have really dirty windshield, or you need more throttle :-)

I have to add about 2 - 3 gallons per tank. Since I don't drive very far, I just top off every weekend

[dale_gribble]

Regular driving, I'll add about a half gallon to gallon a week (2 tanks of gas). If I'm tuning or having fun, much more than that.

[sheston]

It helps my fuel mileage. (If I don't add the spray amount into my calculation)

That means it's green, right?