# water injection before or after fuel injectors?



## weeblebiker (Apr 3, 2003)

so I made a new intake manifold for my 16vT. 








one of the injector banks will be used for water. I think it would be best to spray the fuel in first and the water in second. any educated input would be apreciated


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## BLSport (Dec 24, 2005)

Nice project you have there! :beer:

Can't say my input would necessarily be educated, as I don't have personal experience with this particular configuration, however my gut feel would be to locate the fuel injectors as close to the factory location/orientation as possible, such that the injection pattern in the ports would be similar to that of original.

What is your goal for the water injection? Please describe your intentions for the balance of your engine setup.


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## weeblebiker (Apr 3, 2003)

I would agree about the location except that on cis to efi conversion, the injector tips are siiting 2" behind the tips of the cis nozzles so that location is less than optimum from the get go."


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## BLSport (Dec 24, 2005)

Understood.

Locating the fuel injectors a bit further upstream of the original location might normally have some negative effect on idle and low part-throttle quality, but this effect (if any) would likely be mitigated to a good degree in your case by the turbulence created just downstream of the throttle plates.

Either of the two injector locations seems like it would work for the water, with probably a negligible difference in performance between them, provided you can achieve decent atomization with your injection nozzles. The water will only be getting into the mix as boost comes on and port velocities are on the rise, so it'll be a very short trip to the combustion chambers either way.

If you're leaning toward using the downstream location for the water, I say go for it. You certainly seem like the adventurous tinkering type (compliment :beer, give it a try and let us know how you make out. :thumbup:


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## weeblebiker (Apr 3, 2003)

water is going into the cis down stream.
the up stream angle of the injector portsis almoost pointed at the intake valves anyway.


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## BLSport (Dec 24, 2005)

Best of luck with the project, I'm looking forward to hearing the results. :thumbup:


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## weeblebiker (Apr 3, 2003)

water injectors are done
3/8 brass rod tapped for the spray nozzle and push to connect. 3/8" compression olive soldered on. 3 -204 o-rings and a 1/4" stainless washer using the push to connect fitting to put compression on the o-rings to lock em in place. stock cis injector holders. nozzle end is not sealed to allow the rail to see manifold pressure. but can easily be sealed with a 3/8 id-1/2"od o-ring
somewhat concerend how having a rail connecting the runners below the fuel injectors will effect idle, how much idle air will be pulled from the rail @ 900 rpm. 










still playing with fitment. will go with an air water intercooler as money permits, but initial testing and tuning will be done sanse intercooler


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## redefine6 (Jun 24, 2009)

nice work man. how many hours did you put into that manifold?


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## weeblebiker (Apr 3, 2003)

not as many as the time planing out each step. had to plan out how every aspect of the manifold would play out with instillation and tuning before I made each cut. it took month/years of planning, but maybe 4 hours of machine time.


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