[s-cars] Need more info on Water Injection

[manuel]

S-Heads,

I'm looking for more feedback on water injection.  I've received some 
valuable info from some of you already but I have just spoken to someone 
with a negative opinion on water injection, so I'd like to see what you all 
may think.

For frame of reference, this guy is a mechanic (although not Audi), has a 9 
second Honda that only runs 15 psi of boost. He's also an instructor at a 
local track.  Other than that I don't know him from Adam.

It took me a minute to explain that I didn't have a twin turbo V8, and I 
had to keep reminding him that I was seeing 22 lbs of peak boost, not 26. 
 And that my turbo wasn't a K24.

For point of reference I am running RS2 less cams and MAF, Mihnea Chipset 
(3 Bar PT), Forge Bypass, Samco's, Big Reds on Euro boat anchors, H&R 
29771's (S6+) springs w/ Bilsteins, and HRSB.

I mentioned that my interest was in always trying to reduce the likelyhood 
of detonation and solve/reduce the heat soak problems that are evident 
during prolonged sessions of heavy boost.

His comments were as follows;

1. Your running way too much boost on pump gas, if you want my opinion 
you'd better reduce your boost on your tiny turbo. (I had actually 
instructed Mihnea to tune conservatively due to my concern regarding 
detonation (car previously had MTM 1+ that would ping on occasion))
2. Running that much boost is beyond the turbo's efficiency range (I 
actually have not seen the boost maps for the RS2, but had confidence in 
Mihnea's tuning)
3. Water Injection is old technology (when I asked what  he had installed 
he said one of the early Aquamist Systems) and is a band aid for my use. In 
about a years time the new gel heatsink materials will reduce the costs of 
intercoolers.
4. I should save my money and put it toward a bigger intercooler (although 
he did offer up that using a small turbo to push thru a bigger intercooler 
would reduce the turbo's efficiency)
5. If you want more power you'll need a bigger turbo and bigger intercooler 
(obvious, but I didn't want to aggravate him, I just wanted to get his 
feedback on water injection)
6. It will get expensive buying alcohol to add to a other than pur water 
mix.
7. Water Injection will lower the horsepower by about 30-40 horsepower.
8. When I asked him what type of delta he saw in his intake temperatures 
when he ran his WI system, he said about 30-40 degree's (I am assuming 
thats in Farenheit, not Celsius since he's here in the US).  I believe he 
said from 170 down to 130 F.

I am trying to decide between the FMIC option which I believe is ballpark 
2k USD and 500-800 water injection.  I plan on keeping my RS2 turbo 
because:
a. I just got it
b. Most driving is in town where I prefer the quicker spool up of a smaller 
turbo
c. If I told my wife I was getting a bigger turbo she'd kill me (although I 
have properly instructed my 5 year old to respond this way to any question 
that has to do with any car problem; "Daddy needs a bigger turbo").

So I am interested in your comments.

Flame on.

Regards,

-manny

--
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.308 / Virus Database: 266.7.4 - Release Date: 3/18/05