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petrich
05-01-2008, 02:49 AM
All,

Am installing the basic system in my R53 supercharged MCS. Am aware of the posted install "how to" for the MCS. The maximum tuned crank power of my water injected and tuned engine will be about 225 whp. Am wondering what nozzle placement will deliver an even injection fluid distribution along the entire stock MINI intake manifold?

The stock intake manifold is a log affair with the compressed air entering from one end of the log. Each of the four intake ports branch off the intake log manifold at a 90 degree angle. The end of the log intake manifold, away from the inlet, is a dead end. This is fine for the air: the fuel is injected directly at each intake port. But, I am concerned that if I inject water/meth at the inlet end of the log manifold, the injection mixture will tend to concentrate at the first couple of intake ports and not result in an even fluid distribution at the far end of the log intake manifold.

I am thinking that I can place two 0.4 nozzels along the log manifold, one at the air entrance and another toward the far end. Is this reasonable?

With two 0.4 nozzles am I going to inject too much water/meth fluid for this 225 whp engine?

While I am at it, I have another question about installing a priming pump at my water reservoir. My water reservoir is in the trunk. I can easily install a high capacity water pump to prime the water injection pump. My water pump is capable of 60 psi. Is 60 psi too much priming pressure for the Aquamist injection pump? Or, will that be okay?

All help will be appreciated. Thank you in advance.

John Petrich in Seattle, WA

keithmac
05-01-2008, 11:40 PM
I found a nozzle per runner gave me the best results on a log style manifold, link to a pic here http://members.aol.com/chappyrouter/gto/pics/4.jpg.

If you`re running mainly methanol you may be able to get away with 1 or 2 jets but water does`t like the log manifolds in my experience.

4 0.3mm port injectors should work well for you, do you know your max fuel flow?.

petrich
06-01-2008, 12:05 AM
Keith,

I'll follow the link and see what it says. Thanks

No, I don't know my fuel flow, that is why I quoted the 225bhp figure instead. Must be some rough equivalence between bhp and fuel flow. What does your VW flow? Do you know?

I am inclined, as you suggested, to install multiple nozzles. I looked at the Aquamist replacement parts available here in the USA and the smallest size I saw was 0.4. Didn't see a 0.3 nozzle listed.

Am doing the math: 0.3 X 4 nozzles = flow much greater than a 1.0 nozzle. From the drift of my reading so far, engines of about my bhp output are using a single 0.6 nozzle. What to do? Want maximum detonation suppression but don't want to drown the engine in water / meth.

Took a long look at the intake manifold today. Have located a suitable space on the inlet end, after the air has turned into the manifold, where the supercharged air flow is directed straight down the inside of the manifold. An injector at this point would offer the maximum possibility of a relatively even distribution of injection fluid all along the manifold. The atomized mixture wouldn't have to turn any corners except to get into each individual intake runner. The 'how to' post for the R53 MINI depicts the injector nozzle located on an easily accessible, but curved portion of the intake plumbing, near the intercooler outlet. I can imagine the atomized mixture not making the curves very well.

Anyway, Keith, thanks for the input and I'd appreciate any additional comments regarding this post. I'll check out your link immediately and see what I can see.

Regards,
John Petrich in Seattle, WA

keithmac
06-01-2008, 01:27 AM
The VW has Bosch 440 injectors in it, I think max flow is approx 1.5l/min at 15psi boost. 20% water would equal 300cc/min and 4 0.3mm jets would supply approx 320cc/min so not far off.

Nozzle placement directly after IC would give more time for water to cool the charge air, close to the log manifold may leave you with bigger droplets that won`t navigate the manifold as well?. It`s trial and error to a point, you need to find out what the best spot is for your engine.

Have you go any pictures of your engine setup?.