Stage 3 Methanol Injection - Spray and Play
Horse Sense: The steady progress we've made with our project car's rear-wheel horsepower/torque certainly has been amazing. In our quest for more performance, we've gained a greater appreciation for the enthusiasts we've endearingly chastised for racing the dyno instead of racing their 'Stangs on the dragstrip. While blasting 'Stangs down the quarter-mile will always be our favorite performance evaluator, the work we've done on the dyno has given us a better understanding of just how good it feels when an engine in a dyno-tested 'Stang goes to full scream, the rollers spin furiously, and the graph shows more power than originally thought possible.
Although Editor Turner's feature story on our '86 T-top coupe LX (Top This," Jan. '08, p. 102) gives the impression that we've reached a closing point for a wonderful project, the saga of our latest flagship 'Stang continues.
To tell you the truth, we really don't know exactly when we'll stop reporting on our exploits with the project ride, as it seems there are countless modifications that can still be made, including the project we're embarking on in this report. There are other upgrades on the horizon to further solidify our T-top coupe's status as one of the baddest Fox-Rod project Mustangs in history.
One thing we're learning as we continue using the dyno to fine-tune the 'Stang's engine is that there's definitely a mountain of difference between a combination's actual power output and something we call theoretical horsepower. That's horsepower that gearheads believe their Mustang's bullet should make based on its internal components, power adders, and so on.
For example, based on an assessment of its parts, we originally forecasted (hoped) the supercharged 347 stroker in our coupe would throw down 600 to 650 rwhp; all the parts to accomplish this goal were in place. However, we didn't reach the milestone with the original bullet due to its unfortunate early demise (Full-Throttle Meltdown," Jan. '08, p. 68) during a dragstrip test. The best horsepower/torque achieved with the 347 was 473.34 hp/476.51 lb-ft at 5,000 rpm, with the torque converter locked, barely 8 psi of boost (thanks to a slipping blower belt), and 91-octane pump gas.
A freshened 350ci bullet now rests between the fenders of the project 'Stang. With the corrections we've made in the blower department (a larger-diameter main idler pulley and the addition of a second idler pulley for improved belt tension to create 20 psi of boost), the addition of higher-octane fuel (VP Racing Fuel's MS 109E instead of 91-octane pump gas), an Aeromotive A1000 fuel pump, and spot-on FAST XFI tuning by Harv of HMS Performance, the coupe stands high and mighty with 811.28 horses and 700.25 lb-ft of torque available at the back tires.
One interesting but completely unscientific theory on horsepower is that it always seeks and usually finds the weakest link in an engine or drivetrain. While there may be some truth to this idea, the real deal is that a high-performance Mustang should be outfitted with parts that are designed and manufactured to make, or support, a specified amount of power.
This became blatantly clear for us during our last dyno session, when we discovered our original engine's 650cc (approximately 65-lb/hr) fuel injectors are far from capable of supporting the 800-plus horsepower that the rebuilt bullet produces.
While injectors typically run at and should not exceed 80- to 85-percent duty cycle (0.80/0.85) at 60.5 psi of brake specific fuel consumption in a supercharged application, we're now experiencing 100 percent duty cycle at 5,500 rpm (762.33 hp). Duty cycle refers to the amount of time the injectors must remain open and flowing in order to feed the engine its required amount of fuel. With the injectors maxing out so soon, we're asking for serious trouble if we continue trying to eke more performance from our engine. The blown stroker gives every indication that once it has fuel, it will put up even bigger numbers.
Correcting our fuel-injector problem is mandatory. However, in our tests, we've also noticed that air, more specifically hot air, has also hindered the overall performance of our Mustang. The inlet-air system for the coupe's stroker/blower package doesn't include an intercooler or a heat exchanger, and thus, air-charge temperatures have been measured at approximately 200 degrees Fahrenheit.
To correct both problems, we're installing Ford Racing Performance Parts' 150-lb/hr fuel injectors (PN M-9593-E303) and the all-new Stage-3G Boost Cooler system (PN 20050; $599) from the water-methanol-injection lords at Snow Performance.
The Stage-3G setup is the center of attention in this tech effort, mostly due to interesting new technology called True 2d Injection Control. It definitely sets this version apart from previous iterations of the Boost Cooler.
Unlike the Stage 1 (fixed shot) and Stage 2 (variable shot) boost coolers, which are triggered by boost or are mass air-voltage referenced, Snow's Stage 3G water-meth system is a self-tuning, variable-flow unit that uses fuel-injector duty cycle and a blower or turbocharger's boost signal to control injection.
Once the injectors are swapped and the boost cooler kit is installed, we'll connect our coupe to the Dynapack Evolution 4000 chassis dyno at Extreme Automotive in Canoga Park, California, where Harv will tickle the laptop's keyboard and dial in an XFI tune for maximum power with the new injectors, and then establish a calibration for the engine when it's under the influence of Snow's Boost Juice water-meth mixture.
For our application, we're not expecting a gargantuan increase in horsepower and torque when the spray is applied, because our blown 350 is run with VP's MS 109 E race gas as opposed to 91-octane fuel. Impressive power gains are usually achieved when water-methanol injection is introduced to boost-induced engines that run on pump gas, as we learned in our study on Snow's Shelby GT 500 system (Gorilla in the Mist," Dec. '07, p. 152).
In this exercise, we're installing the Boost Cooler with hopes that it will drop our engine's intake-air-charge temperature significantly lower than the 200-degree temps we saw in our last dyno session without negatively affecting the blown beast's horsepower and torque.
Speaking of horsepower and torque, keep in mind that our T-top coupe is a registered, insured, street-driven 'Stang. We're proud of the car, but we have to admit that with more than 800 horses, it's a handful on the street, despite the fact it sits on Drag Radial tires. Quite frankly, monster performance in a street car is a bittersweet thing. We love the feeling of being pushed back in the seat by power and torque, but losing traction and control of the car on a neighborhood street or highway (even the deserted ones) or being nailed for speeding are possible negatives for mega-powered street cars that aren't cool at all.
Fear not, the only disaster we've suffered thus far was the engine mishap previously detailed. The coupe's sleeper appearance makes the police drive right by, and its panels are straight. The plan is to keep things that way by driving the 'Stang with respect to the horsepower it's throwing down when we're cruising, and saving the opportunities to cut it completely loose for the dragstrip only.
Extreme's Saul The Surgeon" Gutierrez is taking care of the injector swap and installing the Stage 3G Boost Cooler's hardware, and your tech editor is responsible for doing the simple math required for dialing in gain for the water-meth shot. Harv has XFI tuning covered, so you're left with reading on through the following photos and captions to see how this project pans out.
We disconnected the negative battery cable, and Saul routed the wires from the controller's harness into the 'Stang's cockpit. Wiring is simple, as it's only a matter of connecting five color-coded wires from the harness to their corresponding components (red/switched 12V, yellow/any negative fuel-injector harness wire, green/Boost Cooler pump, black/ground, and gray/Boost Cooler touch-screen display). Four additional wires extend from the other side of the controller and allow optional components such as a fluid-level switch, auxiliary 12V output, SafeInjection trigger, and flow-signal output. Unfortunately, time constraints forced us to hastily plumb and wire the system for basic operation in this tech exercise, but we've cleaned things up considerably since this photo was taken.
These photos depict the bread and butter of the Stage 3G Boost Cooler system's True 2d Injection Control, which uses engine fueling and boost pressure to ensure accurate injection of water-methanol. We used this vacuum T-fitting to tap into a boost source and spliced the controller's Yellow wire into the negative/ground side of the injector harness (also a yellow wire on our XFI harness) at the number-one cylinder.




The kit includes wire-splice connectors for this task, but we recommend directly splicing it into the injector harness and securing the connection with solder. Protect it with shrink tubing to reduce the chances of grounding the circuit, which could cause an injector to hang open and possibly damage the engine.






The first step in dialing in the water-meth system is selecting the setup mode on the LCD touch-screen controller and entering information the controller requires (boost psi to start injection, flywheel horsepower, nozzle size, and pump size) for programming the injection's amount and rate. With the setup data entered, we made a series of dyno runs with the system in peak-and-hold mode to determine the peak duty cycle for our new fuel injectors. Stage 3G's injection control algorithm is based on 85 percent duty cycle, which our 150-lb/hr injectors are below. Once injector duty cycle has been confirmed (48 percent), we subtracted that amount from 85 and entered the remainder (37) as the amount of gain (fine-tuning percentage) to the injection curve.
Harv of HMS Performance is the man when it comes to manipulating FAST's XFI engine management system. While theoretically, our 150-lb/hr fuel-injector upgrade is actually better suited for a 1,100-plus horsepower application, it didn't take Harv long to duplicate the 811 horsepower we saw with maxed-out 650cc injectors, and then extend the engine's performance envelope by finding more than 10 additional horsepower and 22 lb-ft of torque. This thing can easily make more horsepower with an intercooler, but the tune is safe and the engine now makes more than enough horsepower for the street," says Harv. With the big injectors, you'll lose the crack-of-the-key starting that is one of the cooler aspects of fuel-injected, high-horsepower street cars (we now have to give the engine a little throttle for cold starts), but that's about the only thing you give up when you run big injectors. The car's driveability will still be fine."
We checked spark plugs and were happy to see their cocoa brown color return with the changes Harv made in the XFI fuel tables. Initial hits on the dyno with the bigger injectors brought about heavy black smoke that's the telltale mark of a rich mixture, and early inspections of the plugs confirmed it. Harv dialed a good air/fuel burn and smooth idle into our coupe's bullet, and then manipulated timing and decreased fuel to allow water-methanol to make the difference we were looking for in terms of lowering our engine's inlet-air-charge temperature without sacrificing any of the performance we gained during the dyno session.
The monitor screen displays real-time data for injector duty cycle, boost pressure, and water-meth injection rate. The Stage 3G system allows you to fine-tune the injection rate up or down on the fly by simply touching the screen to add or subtract gain.







Our combination of the A.R.E. Performance-rebuilt powerplant and Paxton Novi 2000 supercharger made a brief stop at 670 rwhp when we tested it just prior to leaving for our PINKS All Out experience (Lights, Cameras...Action!," Mar. '08, p. 128). A.R.E. Performance is formerly known as Big Terry's Engine Shop in Simi Valley, California, but still owned by Rocco Acerrio.
Those of you who paid close attention to the story (i.e., read Horse Sense) probably noticed that not long after our return from Las Vegas, our project T-top coupe's blown 350 (enough with the Chevy displacement" comments-it's just the way the math worked out) laid down a impressive, nonintercooled 811 horses (700 lb-ft of torque) on Extreme Automotive's Dynapack Evolution 4000 rear-wheel dyno.
Our goal since we installed the new engine has been to overcome setbacks we've experienced (fuel injectors) and to improve our engine's XFI tune. With Ford Racing Performance Parts' 150-lb/hr fuel injectors in place and Snow Performance's Stage 3G Boost Cooler being employed to bring inlet-air temperature down to a more efficient level for the engine's power and torque range, we're confident that we're now on the right track for achieving a solid and safe tune that will produce great performance.
The dyno chart in this report includes our pre-PINKS performance with 650cc fuel injectors. It also reflects the horsepower/torque positives that were achieved through Harv's mastery of XFI, as well as the larger (safer) tuning window that was created by installing the bigger injectors (duty cycle never topped 50 percent at any time during our dyno session) and using VP MS 109 E fuel. We definitely need to shout out props to A.R.E. Performance for an engine that stood up to 15 consecutive dyno pulls and remained consistent with its middle-800 peak horsepower and 700-plus lb-ft of torque output (with a whopping 830/727 on our first pull after lunch), when test variables (ambient temp, 0-6,000-rpm scale, cool down time, and so on) remained unchanged.
More important in this case is the fact that we learned there's also a lot of good that can be said about cooling supercharged inlet air with water-meth. Snow's new Stage 3G Boost Cooler system was easy to work with and calibrate, and it showed us considerably lower inlet-air temperatures than we previously had. The largest temperature drop we experienced was 44 degrees, from 184 to 140 degrees Fahrenheit, and one interesting discovery in our test is the 0.8 psi increase in boost at 3,266 rpm, when we put meth in the mix after the change to 150-lb/hr injectors.
While we realize the temperature decrease doesn't compare with the below-ambient levels that can be achieved with an intercooler (we'd love to have the condensation and all-out frost on the blower's discharge tube that a 'cooler or shot of nitrous can cause), we're impressed and we're fairly certain that deeper cooling can be gained with the addition of a second nozzle for the water-meth injection.
Sometimes, it's all about experimenting when it comes to making a 'Stang better. We plan to continue trying new parts and concepts in our ongoing effort to improve our project T-top coupe, and we'll definitely keep you posted on the results, good and bad, of all our doings.
CLICK HERE TO SEE THE FULL DYNO CHART FROM OUR WATER/METHANOL INJECTION TEST

Photo Gallery: 1986 Ford Mustang - Stage 3 Methanol Injection - 5.0 Mustang & Super Fords Magazine



Read More | Digg It | Add to del.icio.us


Full Story...