Three-Valve Water/Meth Injection - Blizzard Boost

Think of this month's Three-Valve experiment as an extension of the projects presented in '05-'13 Mustang Performance. Given the high level of excitement surrounding the Coyote 'Stangs, we believe giving the Three-Valves a little extra shine is worthwhile. The market for '05-'10s took a serious nosedive when the latest ponies were released. Affordable, ready-to-modify S197s are now as close as the classifieds.

One of the stories in the special issue involves installing a Roush Performance 2.3-liter supercharger on JC Cascio's '07 Mustang GT (Next Phase," p. 56). The project was quite successful, and its results clearly manifest the benefit of adding a supercharger to an otherwise stock Three-Valve 4.6. While the blower's power-enhancing properties may be enough for some enthusiasts, we're keenly aware that most hard-core 'Stangbangers have a need for more power.

With superchargers (centrifugal and positive displacement) and turbos commanding a lion's share of the S197 power-adder market these days, detonation is one of their negative byproducts when an engine's tune or fuel isn't up to par.

Of course, in such cases, conventional thought says just back the timing down and use higher-octane fuel, and everything will be OK. While that's certainly true in theory, the idea is moreso a high- performance irony, as most hopped-up Mustang engines thrive on both timing advance and high-octane fuel.

The water/methanol-injection experts at Snow Performance definitely know a thing or two when it comes to pulling the end around on that timing-and-fuel catch-22.

Our water/methanol mixture (a 49-percent/51-percent blend of each) basically functions as an intercooler for boosted applications," company-owner Matt Snow said. As a cooler and subsequently, a fuel-octane enhancer, water/meth allows users to go beyond the typical limits of 91-octane fuel when they want to increase timing and boost."

After discussing with Matt our interest in working with water/methanol injection on a supercharged Three-Valve 'Stang, Snow Performance sent us its Stage 3 MPG-Max Boost Cooler system (PN 20150; $795) to install on Grant Gross's 2008 Roush 428R Mustang. The Stage 3 water/meth strategy features a dual-nozzle injection scheme, which enhances both fuel mileage and power, by calculating load and delivering water/meth according to fuel-injector pulse width, the amount of boost, or a combination of both.

Our past efforts using water/methanol injection have yielded good results. For power gain, we've seen it increase power on factory-blown Cobras and GT500s by 20-40 horses. On the economy side, fuel-mileage results after injecting water/methanol in a naturally aspirated, Three-Valve '07 GT, showed that the mixture is conducive to mild fuel-mileage increases ... on local-roads and freeway driving.

Grant's Three-Valve Pony features a small, 1.9-liter Roush supercharger that's been treated to a Steigmeier port job, and throws down 408 rwhp (on 10 psi of boost) on the Dynojet chassis dyno at GTR High Performance. If you want to know how this setup responds to Snow's water/methanol injection, move along now through the photos and captions, which cover highlights of Ricardo Topete's installation of the Boost Cooler system, and results of our dyno testing.

Horse Sense: Are you a '11-'13 Mustang GT owner? Do you plan on being one at some point fairly soon? If you answered yes" to either of those questions, please visit one of our online communication vessels (www.50mustangandsuperfords.com, www.facebook.com/50mustangmag, www.twitter.com/@FiveOhMag) and let us know which mods you're considering for the new Pony, and how soon after acquiring the car will you begin making changes.

On the Dyno

With 91-octane fuel, the supercharged Pony maxed out at just over 400 horses at the feet using 21 degrees of timing advance at the top of the run. As you see in the dyno hit labeled Snow (91-octane fuel and water/meth), Chris Jones of Blow-By Racing was able to add a considerable amount of timing advance, yet still maintain a safe air/fuel ratio of 11.1 and increase power, largely in the midrange section of the rpm band (3,500-5,000 rpm).

While we're pleased to see water/methanol do its thing with boost and making horsepower, we're more impressed by the blower and Three-Valve engine's response to the mixture on the torque side of the equation. A larger supercharger, such as the aforementioned 2.3-liter Roush TVS that we installed on JC Cascio's S197, certainly will benefit from water/meth in the high-rpm/high-boost area. However, for our exercise, the dynamic gain is marked torque increase--low-end grunt, which is exactly what Grant will experience every time he punches the pedal to the mat.