9 replies to this topic

[m1tch]

Hi guys, just researching about this, my mate has a midas with a full a series race engine in it, it has nitrous and methonol injection. The methonol is kept in a HUGE washer bottle in the engine bay and is fed directly into the weber carbs.

I asked him about what I needed to put it in mine (he will be helping me rebuild my 1275 engine and box soon and is also installing his nitrous on my car so we can beat lots of stuff down the drag strip at Santa pod lol)

He said I needed a venturi injector to feed the methonol into the fuel line going into the carb (I think thats right). I have found a venturi injector, seems that they are used for irrigation and biodiesel production, where a metered amount of another liquid or air is fed into another.

Has anyone on here installed methonol injectors onto their car? I also run an RX7 and have an electronic water/methonol injection system that uses a pump at 150 psi, but my mates engine has it fed directly into the carb or in intake.

Can someone help me on what I need to get and where I can get it from

Thank you

[CraigyBoy]

U crazy man..... , dont have much useful info for ya, havnt touched that stuff before. I know a methanol project at my Uni was banned for being 'too unsafe'.

Good luck with the project.



Craig

[m1tch]

U crazy man..... , dont have much useful info for ya, havnt touched that stuff before. I know a methanol project at my Uni was banned for being 'too unsafe'.

Good luck with the project.



Craig

Yeah, its only going to be on the track really, it will be running weber carbs which will be plenty on the road lol! My mate is giving my his 1100 sprint box and swapping the 1275 box from the engine he is giving me/helping me rebuild. He is taking the 1275 box for the longer gearing, he has only managed to get his Midas to about 160 so far lol

Does anyone know if the Venturi injectors for irrigation/biodiesel are methonol safe, I know that my inline fuel filter is plastic, so it should be ok and don't worry, I will probably be installing a fire extinguiser in the engine bay. Just want to embarress some expensive cars down the strip lol the nitrous and methonol would be taken out/turned off for the road

Found this sort on ebay (don't worry I will check its correct first lol) would this sort of thing be what I need to find? :

http://cgi.ebay.co.u...d...93:1|294:50

[dklawson]

I suggest you Google the topic of "water injection" and also Google (and check eBay) for information on the company "Spearco".

Methanol/water injection is used to control the onset of detonation in high-compression engines and is sometimes used in turbo applications. I used an inexpensive Spearco system 25+ years ago on a Toyota that I shaved the head on to achieve a 10.5:1 compression. I shaved the head only months before octane ratings of U.S. fuel were drastically reduced and the water injection allowed me to run regular low-octane fuel without pinging.

Some people make the argument that the water/methanol cools the charge too much and costs you power. While it does cool the charge, you are actually able to advance the timing far enough with water injection that the power you loose is more than offset by the power you gain. You also won't have any carbon deposits in the head and exhaust. However, if you drive only short distances around town and run a "regular" exhaust system, you will go through more mufflers.

[m1tch]

I suggest you Google the topic of "water injection" and also Google (and check eBay) for information on the company "Spearco".

Methanol/water injection is used to control the onset of detonation in high-compression engines and is sometimes used in turbo applications. I used an inexpensive Spearco system 25+ years ago on a Toyota that I shaved the head on to achieve a 10.5:1 compression. I shaved the head only months before octane ratings of U.S. fuel were drastically reduced and the water injection allowed me to run regular low-octane fuel without pinging.

Some people make the argument that the water/methanol cools the charge too much and costs you power. While it does cool the charge, you are actually able to advance the timing far enough with water injection that the power you loose is more than offset by the power you gain. You also won't have any carbon deposits in the head and exhaust. However, if you drive only short distances around town and run a "regular" exhaust system, you will go through more mufflers.

Yeah I will be running a WI system in my turbocharged RX7 so it doesn't detonate at high boost, thing is, that is electronic and Im using weber carbs, so I was told I would need Venturi injectors that would passivly inject the methonol into the engine, rather than activly such as the WI system on my RX7

[dklawson]

The installation can be much simpler on a normally aspirated engine as there is no positive manifold pressure to overcome.

The old, cheap Spearco system I ran was VERY simple. It used what looked like a windshield wiper reservoir (with low pressure sprayer pump). Connected to the spray motor was a sensor board. One part of the board was connected to the coil (muck like a tach) to sense engine speed. A vacuum sensor on the board was connected to the intake manifold. The board had a VERY simple function. It would look for the manifold vacuum to go towards higher pressure (indicating load and/or wide open throttle). When the board saw the higher pressures and engine speed above a user selectable RPM, it would turn the pump on and start spraying water. The amount of water sprayed by the pump was controlled by orifice plugs placed in the hose which was in turn routed through the air filter cover so it sprayed through a simple nozzle directly down the carb throat.

The "spray" was not atomized at all. It was more like a fine stream of liquid that shot down through the carb and broke up as it hit the inside of the intake manifold... or the throttle butterfly (at part throttle conditions).

Enough history. Most of the "new" systems operate at higher pressures and spray through a proper nozzle to atomize the fluid. The brain that controls the system has also become more sophisticated than the old system. Unfortunately, the high pressure systems cost more money and may be a little more difficult to fine tune. However, I have no first hand experience with them.

[m1tch]

The installation can be much simpler on a normally aspirated engine as there is no positive manifold pressure to overcome.

The old, cheap Spearco system I ran was VERY simple. It used what looked like a windshield wiper reservoir (with low pressure sprayer pump). Connected to the spray motor was a sensor board. One part of the board was connected to the coil (muck like a tach) to sense engine speed. A vacuum sensor on the board was connected to the intake manifold. The board had a VERY simple function. It would look for the manifold vacuum to go towards higher pressure (indicating load and/or wide open throttle). When the board saw the higher pressures and engine speed above a user selectable RPM, it would turn the pump on and start spraying water. The amount of water sprayed by the pump was controlled by orifice plugs placed in the hose which was in turn routed through the air filter cover so it sprayed through a simple nozzle directly down the carb throat.

The "spray" was not atomized at all. It was more like a fine stream of liquid that shot down through the carb and broke up as it hit the inside of the intake manifold... or the throttle butterfly (at part throttle conditions).

Enough history. Most of the "new" systems operate at higher pressures and spray through a proper nozzle to atomize the fluid. The brain that controls the system has also become more sophisticated than the old system. Unfortunately, the high pressure systems cost more money and may be a little more difficult to fine tune. However, I have no first hand experience with them.

So your system was a separate system to that of the fuel then?

[dklawson]

Oh yes, very separate. You didn't mix the water or alcohol with the fuel. The fluid was simply sprayed down the carb throat and atomized as it was drawn into the engine.

The new systems still operate this way but typically use "real" pumps with enough pressure to atomize the fluid leaving the nozzle. Most of these systems are aimed at the turbo crowd who will spray the fluid in to cool the charge and prevent detonation. Like my old system, they do NOT mix the water or methanol with the fuel.

Google for "Coolmist" and I think you'll find a lot of systems aimed at turbo intercooling using methanol.

[m1tch]

Oh yes, very separate. You didn't mix the water or alcohol with the fuel. The fluid was simply sprayed down the carb throat and atomized as it was drawn into the engine.

The new systems still operate this way but typically use "real" pumps with enough pressure to atomize the fluid leaving the nozzle. Most of these systems are aimed at the turbo crowd who will spray the fluid in to cool the charge and prevent detonation. Like my old system, they do NOT mix the water or methanol with the fuel.

Google for "Coolmist" and I think you'll find a lot of systems aimed at turbo intercooling using methanol.

Yeah I have a full devilsown kit for my RX7 runs at 150psi lol as you do lol

sorry, just to check, did you spray it in before the carb needle or afterwards? (its cause I will have a twin weber so I might need two lol) was your sprayer for safety or power?

[dklawson]

My old Spearco system was used on my Toyota which had a downdraft 2-barrel carb, not an SU. Regardless, it was spraying the water down through the carb throat from the top of the air cleaner housing. Were I doing this on a car with an SU, I'd spray in exactly the same place... from the cover of the air filter housing down the carb throat.

I think your kit sounds much more sophisticated than the low-pressure device I ran 25 years ago. I still see the old Spearco kits come up on eBay every now and then. The NOS kits sell for a lot of money considering what they are.

You asked if I used the Spearco kit for safety or power. I think I mentioned above that shortly after I shaved the head of the Toyota to raise the compression ration to 10.5:1, they dropped the octane rating of U.S. fuels. I was getting detonation if I didn't run premium fuel. I decided to try the water injection on the advice of a friend. It worked very well, allowing me to advance the timing further and run regular (low-octane) fuel. So... you could say I used the kit to protect my engine AND to get more power. Apart from going through a lot of mufflers I was very pleased with the system.

EDIT:
Sorry, I meant to add that if I were running dual carbs I would consider using two nozzles and a T fitting to split the flow. I'd spray down into each carb from its air cleaner. There may be some info on the web about this but it may be hard to find. As I mentioned, water/methanol injection is used primarily (these days) by guys running turbos so they may be dealing more with fuel injection systems, not carbs.

Edited by dklawson, 06 July 2009 - 11:09 PM.