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Discussion Starter · #1 ·
I need to work out how many water injection nozzles to use so first thing is to figure out how much fuel the T8 injectors inject per min @ WOT.

Any idea's?


I need to inject between 10 - 15 % water to fuel ratio, the nozzles i've got run @ 2l per hour, which is'nt a lot, so I think i'm going to have 2 firing @ 0.8 bar then the second 2 firing @ 1 bar.

So if 4 are injecting, that's 8,000cc per hour, 133cc per min.

If i use 5, bank of 3 then 2 i'll be injecting 10,000cc per hour or 167cc per min.
 

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Discussion Starter · #2 ·
Injectors

Just dug through on a search and found the rating for T16 injectors.

My 91T16 has orange topped injectors. According to the Saab workshop manual for Lucas Inj they should have a flow of 216-264 ml/min. Does this mean there are 2 types or that this is the acceptable flow rate range?
so if the 8v injectors are similar, say 250ml per min, 1 litre for all 4 per min that means i need to inject between 100 & 150ml of water per min.

So if 1 misting nozzle injects 2000/60 = 33ml per min i'm going to need between 3 and 5 nozzles, which will give 99ml to 165ml per min.

I think i'm going to use all 5, have 3 come on @ 0.8 bar and the following 2 @ 1 bar.

Will carry on searching to see if i can find the values for an 8v turbo

Anyone want to chuck in their 2c worth?
 

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Discussion Starter · #4 ·
lb/hour

Does that mean i've got to go and weigh a litre of fuel to see what it works out to be?

Doh!
 

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Yes! :cheesy:

Not really :)

1lb/hr = 10.5cc, so 21lb/hr = 220.5cc and 27lb/hr = 283.5cc. Remember that those values are for a 16v FPT.

Measuring injector flow by mass instead of volume is more relevant, as the value will remain meaningful across all temperatures. Hot fuel is less dense and occupies greater volume than cold fuel, yet will burn less oxygen. Same principle as for air mass vs. volume.

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Discussion Starter · #6 ·
weight of fuel

Any suggestions as to how many 33cc/min or 33grammes/min misting nozzles i should use then?

Perhaps i should do a poll:cheesy:

By chance then i think that i may have exactly the right amount (5).

I'll await PDA & Tomases input aswell, should get there eventually;) .

I think i can have the best part of my misting system sorted by the weekend, just need something to mount the nozzles into the inlet now, have a cunning plan so will see if it works.

Here's a pic of the nozzles
 

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Si said:
I'll await PDA & Tomases input aswell, should get there eventually;) .
I'm here :cheesy: :cheesy:

at the moment I'm thinking ;oops: ;oops:

Paul

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Sleeper baby, no show & all GO.............................
 

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Discussion Starter · #8 · (Edited)
misty mountain hop

Had a test run using 4 nozzles. Looks misty!

Next i'm going to try cutting each supply tube to a different length and see if i can stagger the nozzles kicking in, think it would be better to have them going on 1 by 1 rather than the whole lot at once.


I've kinda got the housing for them figured, just need to pop down to b n q to get some 12mm steel tube.

http://www.turbocalculator.com/water-injection.html

Interesting link, still dont know how much fuel @ wot though:cry:
 

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Discussion Starter · #10 ·
Ahhhhgggg

Jez, you had me all excited for a minute, i thought you were going to contribute some wisdom from your fountain of knowledge.


Ahh well.:lol:
 

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:cheesy: :cheesy: :cheesy: :cheesy: what jezza !!


no I'm still thinking.............;oops:

Paul

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Sleeper baby, no show & all GO...........................
 
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