5.0 Mustang & Super FordsHow To Engine
Mustang GT Turbo Kit - Tag-Team Turbo
Boost For Your SOHC Modular From Innovative Turbo Solutions And Pro-M Racing
Horse Sense: Blow-through turbo setups such as this one place the mass air meter downstream of both the turbo and the blow-off/bypass valve, ensuring the meter reads only the air actually entering the intake.
We shouldn't have to tell you that turbochargers have been phenomenally successful on the dragstrip and are likely to turn up anywhere Mustangs compete for quarter-mile dominance. Until recently, however, this "they're everywhere" observation could not be made on the streets, where superchargers have undoubtedly had the upper hand in terms of sales success. But things have been heating up-so to speak-when it comes to Mustang street turbo kits, with at least a couple players stepping forward with kits for both pushrod and modular applications.
One of those new arrivals on the turbo kit-building scene is Innovative Turbo Solutions (ITS) out of Dayton, Ohio (not to be confused with California's Innovative Turbo Systems, a manufacturer of turbochargers and associated hardware). ITS does not build turbo-chargers-the guys there simply design and engineer the stuff necessary to house and feed one in the confined spaces of a Mustang's engine bay. Forgive that use of the word "simply," because the development of a good turbo kit is a complicated task.
By itself, a street-size turbo is a fairly compact lump-certainly no larger than the average centrifugal supercharger. But since it's spun by exhaust gases, routing the serpentine array of pipes from a pair of cylinder heads-without roasting anything in the process-has always been one of the bigger challenges for street turbo-kit developers. This space problem is compounded when exhaling through an intercooler. Despite this limited underhood acreage, ITS has so far been able to develop kits for pushrod, SOHC, and even DOHC Mustangs. This time, we'll take a look at a preproduction version of ITS' 4.6 Two-Valve Stage II (intercooled) package, which retails for $4,795 and includes a tubular K-member and A-arms, as well as coilovers, to provide the necessary elbowroom for all the turbo and 'cooler plumbing.
By now you may be wondering what Pro-M Racing has to do with all this. Skilled though they are as fabricators, and brimming with confidence on how to develop comprehensive Mustang packages, the guys at ITS freely admit to knowing precisely nothing about how to tune for a turbo's specific air/fuel and spark requirements. So, rather than leave all the tuning issues in the lap of their customers, they wisely turned to the experts at Pro-M Racing to provide that all-important side of the equation. Parent company Pro-M is, of course, famous for its high-flowing mass-air meters, and of late it has been working on a full range of tuning issues through its Pro-M Racing subsidiary, culminating in some amazingly potent calibration software that we'll tell you more about in upcoming issues. To accompany the turbo on our subject '01 GT, Pro-M offers a "tuner kit" for $1,600, consisting of a 3-inch Univer mass air meter, 42-lb/hr injectors, a chip calibrated with its new leading-edge proprietary software, and, because of the peculiarities and limitations of the late-model GT's returnless fuel system, an '03 Cobra fuel tank with its dual fuel pumps.
The following is a brief look at what's involved in installation of the turbo and tuner kits, accomplished before our camera's prying eyes at Pro-M Racing's Oak Park, Michigan, facilities. This locale provided handy access to Pro-M's brand-new Mustang MD-1750 loadable chassis dyno, where the impressive results were thoroughly documented. Past efforts at Mustang street turbo kits have often been characterized by complicated installations, occasionally involving such unnerving steps as having to relocate/extend brake lines or cut metal out of subframe rails. But from what we observed, if you're not intimidated by the thought of swapping K-members, installing the ITS kit should be a straightforward-if somewhat lengthy-proposition, doable at home but no doubt best accomplished on a hoist. Figure on a good couple days' work, but if this one is any example, the reward will be a modular that feels a couple hundred cubic inches larger.
Everyone was bone tired when, at around 11:30 p.m., the key was cranked and the newly muscled GT came to life and idled perfectly with its Pro-M Racing chip in place-not always the case, as we all know, after installation of a power adder. Unfortunately, we had to boogie and couldn't stick around to watch the next day's dyno session or drive the beast. So we'll have to let the above dyno results do the talking. We've also included Mustang dyno results for a stock '03 Cobra for an interesting comparison-333.4 peak horsepower at 5,700 rpm.
As you can see, peak horsepower was up by more than 60 percent to 373, while torque got a 52 percent boost to more than 415 lb-ft-and, remember, these numbers were generated on the always-conservative Mustang dyno. More important from a daily driving aspect than the peak numbers are some point-to-point observations. By 3,000 rpm, torque is already improved by more than 96 lb-ft, and at 5,000 rpm, power is elevated by more than 141 ponies and torque by more than 148 lb-ft. Speaking of torque-something a stock 4.6 lacks in spades and that a 3,850-pound convertible can really make use of-it crests the 300 lb-ft mark by 2,500 rpm and tops 400 lb-ft by 4,000 revs. This is with a mere 6 psi of boost and what Pro-M Racing's Scott Beer describes as a "very conservative and safe" tune.
As indicated, I didn't get a chance to drive the muscled-up ragtop, but car owner Joe Clark-the most important critic of all-says it "runs and drives great." His biggest problem seems to be how to find traction for all this newfound power at the strip.
Note: The baseline run includes a Pro-M 80mm mass air and cold-air kit, a ported upper intake, and a 70mm throttle body.