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Discussion Starter · #1 · (Edited)
I've been thinking for a few years of trying a pumped alcohol/water injection system on the thingy but may soon trial it on the test bike.

I have fitted this setup to a fair number of cars in the past but never a bike. The carbs aren't ideally set up for a syphonal draw. The butterflies in the keihins could be used for control with miks a little more problematic due to not having butterflies. Slide control can be used but seems less than ideal. So I'm thinking a pumped system with a throttle position switch to trigger the pump.

Once again, this would be easier with the keihins than the miks as the miks have no linkage to add the plunger switch to. The throttle position switch would be difficult to work out here.

As stated before, I have run this in a number of cars in the past. Some didn't show any improvement to either power output or economy but some had large improvements. Particularly an XA falcon 250 cubic inch 6 we had which had sky high compression and pinged without the injection. {too many head shaves and a decked block} It went like stink.

At 10:1 compression {should actually be closer to 11:1 in both the thingy and the thingummy motor in the test bike} the CX motor should be a good candidate. Gains seem to be greater with higher compression. It also helps to prevent knock and pinging from high compression and aggressive ignition advance.

I'll likely go ahead with this when I can more consistently get out to the shed again though having trouble figuring out how to do the switching.

The system itself is fairly simple and would be basically cloned from the economist setup that was sold here many years ago and that I used to clone.

This would be a pumped rather than a syphonal system though with low mounted tank to prevent gravity feeding, likely utilising a windscreen washer pump. I had a similar setup on our commodore that picked up moderate power gains with it running to the twin throat weber fitted. AKA the baloney device. {made in Bologna} This from a later model falcon.

The switching would be the most difficult part and the part I've yet to figure with the miks. I think the keihins would be relatively easy to install switching to the throttle bellcrank on the left carb.

A possibility for injection point is through the intake runner rather than the carb itself. Some experimentation with injector tube {nozzle} size would be required to get the correct spray pattern with the amount of pressure delivered by the pump. Likely in the 1.5 mm range.

This would also allow a greater degree of ignition advance without pinging. Also for higher compression without pinging.

Anyone tried this? Thoughts?
 

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Discussion Starter · #3 ·
I don't really have concerns over the legalities. {which I was unaware of} as the system will be innocuous enough mostly hidden behind the sidecovers.

Safety wise if a sturdy container is used and mounted within the frame where it is protected I am less concerned with the injection tank than the bikes own fuel tank.

With a pressure fed system blown lines must be considered and the possibility accounted for in the way the plumbing is done. Though the size line required is likely 4 mm I see no reason that 6 mm fuel line couldn't be used - except that the brass control tap inlets and outlets are 4 mm. I guess adaptors must be available in materials other than plastic Generally I just plumbed the syphonal systems with vacuum line.

Much of the downside is mitigated with a pumped system set to come on at @ 75 - 80 % throttle input meaning the system is not running at any time it is above idle like a syphonal system. Basically, if you don't arrive at your destination on the fang and shut down immediately the system will flush itself before shutdown. While I'm aware that these systems can cause corrosion I think a pumped system with no syphonal or gravity feed should be OK.
 

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I think it would be an interesting project.(y)..I can remember it being discussed for "worked" CB750 (SOHC) and Z900/1000s street bikes in the past...and i'm sure many found themselves on public roads.
 

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Discussion Starter · #5 ·
I've just had a quick look at SAs rules on this and can't find mention of it. We're generally pretty lax here unless a vehicle has to go over the pits or you have been caught hooning.
 

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Discussion Starter · #7 · (Edited)
Thanks for that Sirfoxx. I've skimmed and will read the article more in depth.

I do tend to think this pump is beyond the requirements for this application. This feller is injecting a turbo'd 2 litre, 200 HP 4 cylinder in one instance and also a larger V8 truck.

Injection pressure shouldn't need to be that high IMHO. Are you feeding yours into a pressurised turbo manifold AFTER boost? Mine is NA and will be assisted by vacuum and these systems can be run by vacuum alone.

Supply volume sounds high to me for this application too. Though nozzle restriction should have a part to play in raising pressure and lowering delivery volume. I'll see if I can find a chart on the internet that gives maximum flow through a given size nozzle at a given pressure. This would alter the ultimate outcome from the pump specs which are possibly max volume at unrestricted flow.

I used to use 1.5 - 2 litre supply bottle for 4 and 6 cylinder vehicles from 1.5 litre to 3.8 litre. Their consumption was generally one fill of water/meth to a 45 - 60 litre tank of fuel with a little left as you can't run the system dry. Most of these were syphonal systems and consumption does rise under pressure.

But at this point you've given me more to consider and some further reading to do.

I'll be back.

EDIT rather than putting the system under control of the pump I am thinking of going with this 80 PSI 5 litres per minute pump which has auto on/off dependent on permitted flow/pressure


under the control of this 12 volt on/off solenoid valve.


Or maybe this one.


I think I've figured out switching with the mikunis. As mentioned earlier they have no bellcrank to work with to operate a plunger switch..

But I figure that if I use a set of mikuni cables for a triple the third cable can be used for switching. Still pondering....
 

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Thanks for that Sirfoxx. I've skimmed and will read the article more in depth.

I do tend to think this pump is beyond the requirements for this application. This feller is injecting a turbo'd 2 litre, 200 HP 4 cylinder in one instance and also a larger V8 truck.

Injection pressure shouldn't need to be that high IMHO. Are you feeding yours into a pressurised turbo manifold AFTER boost? Mine is NA and will be assisted by vacuum and these systems can be run by vacuum alone.
For me, yes. However, my turbo setup is on a carb'd car, not a CX-T. From what I read, the reason people run such high pressure pumps is not to overcome the manifod pressure, its to have the charge properly atomized through the misting nozzle. Flow rate can be changed with the nozzle, though the pressure requirement stays more or less the same.
 

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How many litre per minute nozzle are you running feeding what size motor?

I'm looking at 60s, being the smallest I can find.
liters per minute? most are rated at gallons per hour...however, that can be fixed.
If you want the lowest rated nozzle, it has to be ran at a minimum of 70psi due to the check valve. However, at 100psi it used .59gph, which is .037lpm (I think).
Full Cone No-Drip Misting Nozzle, 303 Stainless Steel, 1/8 NPT Female, 0.75 gph At 100 PSI | McMaster-Carr

Heres a list of the full cone misting nozzles from mcmaster-carr. Not sure if thats a store you have access to down under ;)
Nozzles | McMaster-Carr

I have yet to run water injection. It's something I am still researching. However, if hes feeding both his supercharged truck and turbocharged mr2, 5gph should be fine...Though I may get something closer to 3gph. The motor im messing with is a 1.5L
 

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Discussion Starter · #11 ·
I'll read those when I get a chance.

I may look into brass sprayer nozzles from the irrigation industry. Some mist very finely, especially those intended for ferneries. Unfortunately most are now plastic

But these are also rated at litres per minute.

I actually used to make my own from stainless or brass hobby tube. Crude, I know.
 

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i have used snow performance kits on boats seadoos and the odd bike when boosted they have it dialed in
here is one i used
very nebulous addition to a conventionally aspirated engine even at 11 to1 since in most countries the goverments used the
whole timing a preignition pinging issue to shove 10 percent ethanol down are throats to cure a non issue
so all you are adding is water

that will scrub the valve stems and faces clean but dont think it will make any power addition it may even be a loss
 

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Discussion Starter · #13 ·
The thingy runs switchable pickups to hall. The stock pickups of course give a stock baseline. The hall when switched and gives the same 37 degrees maximum advance. As long as the baseline is 0 degrees. So, aside from the selection of advance curves I can play a little with the baseline.

But I mainly just want to try it on one of these. I've had good results with a few naturally aspirated cars. Nothing from others.

Curiosity mostly
 
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