I wanted to share with you what I have been working on the past few months with reguard to a safe reliable way to run 20+lbs on pump gas and get some input on tuning with meth. I am running a healthy dose of 50/50 water/meth and have been running it with pump gas @ 20lbs for the last few month and the car is running top notch. I am able to do this with a fair amount of safety in case of failure of the injection system by implementing a devise I designed that reverts to the wastegate spring pressure (15lbs) if less than 60lbs of pressure is detected in the alcohol system post solenoid. What this means is if a solenoid fails to open or the pump stops producing pressure, it opens a solenoid that bypasses the boost controller. This has actually saved my *** because one of the solenoids cracked in half during a 4rth gear pull and I lost pressure in the system and boost reverted to 15lbs in the middle of the run.

I was wondering how many of you guys are using meth injection and what AFR's/timing are you tuning for at 20lbs. I am still in the 11.5-12 range at 20lbs, but I know that meth chages the stoich value of the mixture, but as of yet I haven't experienced any knock in my logs. Anyone have any input?

 

Radkins,

That's a kickass idea. I don't have much experience with water/meth injection. I installed a WI kit from CoolingMist and am currently running straight water on my non-intercooled, supercharged FC; however, I'm planning on running a 50/50 mix of denatured alcohol and water. Depending on how well that works for the FC, I'll likely install a similar setup on the FD especially after this idea. I'm tired of paying $5/gallon for race gas.

 

What percentage(as it relates to fuel) are you using? Ie, many agree, that ~10% is a good starting point. I'd love to run my race car on pump, but I think I would be limited to~18 psi on 91. In piston land, there are many guys running ~25psi on pump with no ill effects. In my current scenario, I have an Aquamist, and its sole use is to cool the intake charge. In other words, i tuned w/out water, and am adding it after the fact to make everything a little safer. I think I could stand to run ~18psi(450rwhp on my set-up), and save the ~300.00 a weekend I spend on gas...

BTW, I love montego blue

 

I am running 850/1600 @ 80%, so that figures to be about 62gph of fuel. I am injecting about 15gph of water/meth. That's about 25%, so I am obviously taking out fuel and replacing it with meth and running 12% water.

 

I have been running 20 psi on pump gas with occassional spikes to 23 psi from using the haltech boost control and my engine lived to tell about it... Its not impossible to do, its just the right combination of spark plug heat/cooling mods/afrs and timing...With those boost levels, there is not alot of rooom for error with half assed fuel systems, and mediocre ignitions.. Every precaution must be taken with the supporting cast for the engine to live..But if its done big boost on pump gas is achievable..Max

 

I'm using a water/meth mixture with my Aquamist 2d.
That system reads the duty cycle from the fuel injectors to ghet its signal and be able to maintain a constant water(mixture)/fuel ratio.
I was running a 25% meth mixture but will be increasing that to 66% when the new engine is together.
I was hoping to get up to 18 psi safely on 91 octane with this combo and you have given me hope.

What octane is the pump gas where you are at?
Where are you injecting at?

I would definately be interested in the boost cut system you have developed with the solenoids.

Carl, have you installed the Aquamist yet?

Radkins, here is a link to the aquamist forum that aalso has subtopics discussing mixture ratios and tuning methods:
http://www.aquamist.co.uk/phpBB2/index.php

 

I am running 93 pump. I have checked out that site and it is very informative, but can't seem to find a concrete theory on what the AFR's should be running. If anyone is interested I will draw a block diagram of my system. It is quite simple actually.

 

run 23 to 25 psi all day every day with water injection (100% water only) on pump fuel.

12 deg advance 8 deg split @ high boost

B10EGV plugs or B11EGV's & CDi ignition

10.8:1 AFR to 13.7:1 AFR

15 to 25% water ratio to fuel

It will be reliable and make lots of power too, done this on quite a few cars of the course of a few years all without any reliability issues at all.

I sell kits and calibrate them to suit your application, if you want more detail PM me.

Peter.

 

Peter,

What do you do (if anything) to safeguard against detonation in the case of the WI not working properly?

I'm interested to get other ideas.

 

What are your targer AFR's under boost. I have noticed that it doesn't like AFR's as low as 11.0, you can feel it fall on its face.

BTW, I am spraying pre and post IC.

 

Target is listed above, all ratios between those values work is the basic answer. Up to 500rwhp and its all fairly safe.

Safe guards against detonation? make sure the tank is never low or empty

My personal target for AFR is generaly set around 11.7:1 depends on what I am trying to do and what the car will tollerate and what the conditions (engine and ambient) are like. The ONE BIG thing is the tuning window with WI is enourmous you realy have to **** up bad to get it wrong or to cause any type of damage which is the beauty of it....

 

please draw it out for me... thanks,.

 

What I'll be using when it becomes available

 

Methanol is no joke. My buddy runs 28psi on his VR-4 with a 50/50 denatured alcohol/water mix with no knock.

 

is that the vr4 that raced a black fc lastnight?

 

That is what I want to use but they keep postponing it afaik and I do not want the bulkier version 2 with less features.

 

Available as of today according to the aquamist forum....

 

fug yes, i'll be running 50/50 water/meth on my carb'd setup here soon! WOOOOT!

 

Could you elaborate on the cooling mod topic? I assume you refer to intercooler cooling mods...

 

I second the motion

 

OK, here is a hand drawn diagram I did real quick. Sorry for the sloppyness, maybe someone with some computer skills can make it look better. Anyways, the electrical lines are in red and the water/meth pluming is in blue. Basically what is happening is the the 10psi boost pressure switch will send a signal to the solenoid that is T'ed into the wastegate unless it is interrupted by the 12v relay turning on. The relay is normally closed, so if nothing happens to the relay it will let the signal pass through. The 60psi switch located on the output side on the first stage on the WI (5psi) is monitoring the pressure in the WI lines POST solenoid, and is what will send the signal to interrupt it. When it sees 60psi+ it passes the signal on to the relay blocking the signal from the 10psi swich from reaching the wastegate solenoid. I have a 3 stage setup with another solenoid that opens at 15psi, but I left that out of the diagram. Occasionally in 1st and 2nd gear boost will stick at 15lbs for a split second becaust the pressure hasn't built up enough to kick the 60psi switch on. I will fix this by using a 50psi switch, or I may leave it alone cause it lets me know that the safeguard system is working.

Hope this helps some of you out!

 

where is a good place to buy the ELECTRONIC AIR SOLENOID that opnes the wg signal wing if things are not right?

i looked for a while last night and the cheapest i found was like $45.

there has to be somewhere cheaper. anyway please post where you got yours.


also... is it safe to run water into a hobbs switch?

 

From Mcmaster-carr's website

7877K55
(Same as 7877K5)
Polypropylene Solenoid Valve Wire Leads, 1/8" NPT Female, 150 PSI, 12 VDC
In stock at $18.12 Each

I would not recomend running these in the Alky system itself as they are somewhat cheap and don't withstand the pressure over time.

 

cool deal... how about a hobbs switch... know where to get a good deal on one?

 

I like the idea. I had a similar plan on my water injection set-up to just use a solenoid in the intake pipe before the TB. My dual stage WI uses an accumulator and holds 100psi at all times. I use a nordskog fuel pressure gauge to monitor the water pressure. This accumulator keeps the pump from always coming on while boosting because of the pressure. If my water pressure was to go below 50psi, my fuel pressure gauge would send a signal to my solenoid to open therefore venting any boost pressure. No boost no boom. It would basically work like a pop off valve.