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ace996 ace996 is offline
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Join Date: Feb 2008
Location: Long Island
Posts: 7
Water/Meth injection is a very good mod when used correctly...just like anything else. You can't slap a bigger turbo or engine management or injectors on a motor and run better/safer without doing it the right way. There are different uses for WI (water injection...I'll include meth injeciton, too) and different ways to employ it's benefits.

Using 15-20% of fueling requirements of WI, either 50/50 meth/water or 100% meth, will do wonderous things to your motor's power output...but it will need to be tuned (leaned and advanced timing) or it will probably run way too rich. With proper tuning, you'll find less lag...lower intake temps (meth/water cools air far beyond what intercoolers can do, even going under ambient sometimes)...lower tendency for detonation (water/meth is a very potent race-gas)...and will keep the combustion chamber quite clean.
It's quite frequent to hear of gains of up to 5-10% in rwhp and more in rwtq. I gained a good 40rwhp and 80rwtq on my Subaru STI after adding a meth/water injection system.
The best thing about that there is never heatsoak. The power I had on the first lap of Limerock was the power I had on the 20th lap of Limerock...the consistant power delivery and lack of heatsoaked detonation and power-fade more than made up for the added maintenance of filling the system (I had a 12liter tank mounted in my trunk, only filled it once per month on the street and refilled one-two times per trackday) which is very low compared to the benefits.

I often hear of 930 owners/tuners saying that the car is really limited to 350-400hp because of the fuel system? Well, I'd bet a proper WI system would fix that issue, and allow a much safer engine around the 400hp level. The new kits...Snow, Aquamist, Coolingmist...all have programable controllers that could probably work pretty well to augment a bolt-on 930.
And if the spray is injected just after the intercooler, the vapor would be well atomized by the time the uneven runners would enter the equation.

WI has not been embraced by the P-car world...and that's a real shame. It seems it's still seen as taboo by the old-school tuners, most likely due to inexperience with modern systems.

One day...

Be good,

Here's my STI's AFR/Boost graph...smoother AFRs with higher boost...

And my dyno graph...look at the gains in spool and torque down low!!!!...

Car ran like a beast...awesome.

Last edited by ace996; 02-05-2009 at 07:58 PM..
Old 02-05-2009, 07:48 PM
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