Injection Plus Intercooler

[TPW]

I've been searching through the archives, and can't seem to find a quantitative evaluation of how much more power to expect from adding a water-meth injection system to a turbo diesel with an intercooler. Does anyone have some data on power, or mpg increases after installing injection on a diesel engine with an intercooler?

[rabbid79]

Check out Snow Performance's website for the TDI Jetta.  Obviously, it's intercooled and a diesel.  They claim a pretty big gain in both MPGs and torque/HP.  There's a link to an article from some magazine in there too that does a full review of their system.

[TPW]

That's good data. Thanks!  I wish the system was a little less expensive.

[rabbid79]

Yes, those prices are outrageous.  You could probably roll-your-own for a couple hundred at most.  Some guys just squirt the methanol right at the compressor wheel using a low pressure pump, or by routing boost to the methanol reservoir.  Would this be for your 5000? 

[TPW]

Yes, this is for the 5000.  The thing that makes Snow's system different is the nozzle that is injecting during the wide band of turbo pressures. Does anyone know how this functions differently than the one that injects hat the higher boost pressures?

[rabbid79]

I think what they are doing is injecting an amount of methanol that is proportional to the amount of air (and hence fuel in the case of a gas engine).  This seems like the smart way to do it.  If all a system is doing is injecting based on boost pressures, then it's not seeing the whole picture.

[TPW]

From what I can see on the Snow Performance system, one of the nozzles puts out a constant amount of mix, and another nozzle kicks in at a preset boost level.  I think I could make my own version of this with a much cheaper injection system if I knew what the rated nozzle output of the constant spray is.  Does anyone have a clue what that is?

[RadoTD]

From what I can see on the Snow Performance system, one of the nozzles puts out a constant amount of mix, and another nozzle kicks in at a preset boost level.  I think I could make my own version of this with a much cheaper injection system if I knew what the rated nozzle output of the constant spray is.  Does anyone have a clue what that is?

If you look at this website here http://www.alcoholinjectionsystems.com/Water-Injection-Nozzle/c28/index.html
Their nozzles range from 1GPM up to 14. Biggest kit takes 2 nozzles, so lets say a pair of 10 and 14GPH nozzles are good for 1200hp.. that's 50hp/GPH. So if your goal is 200hp, I'd aim for around 4GPM.
Just a baseline that should get you started...