Eric English
April 9, 2014

Horse Sense

One of the most common themes in Mustangdom is not being able to leave well enough alone. It’s a condition that Marc Sorger surely has, evidenced by a full vinyl wrap that was going on the car as we went to press, along with new wheels. The evolution continues.


Go to the races, a car show, or your local cruise-in these days, and you seemingly can’t turn around without bumping into an engine swap that updates some of the classics of yesterday. We’re surely not complaining, for there are plenty of good reasons to put a LS in a ’66 Nova, a Gen III Hemi in a ’70 Cuda, or one our personal faves—a Coyote in a ’90 Mustang. Simply put, it’s tough to beat the combination of performance, reliability, and driveability you get with a late-model engine. Did we mention fuel economy?

Yet for all the good reasons to follow such trends, Marc Sorger found that repeatable big-time track power wasn’t really the forté of his GT’s stock Three-Valve mod motor. To be specific, it was the supercharged 4.6 in his ’08 GT that caused him woe, so Marc turned to a back-to-basics approach that many an enthusiast will applaud.

Incidentally, Marc bought his car new in 2008 with the intent of keeping it as a stock daily driver. That sounds familiar!

This ’08 GT is covered in a factory white wrapper, but it’s hardly subtle. Prior to installation of the full-race 358, owner Marc Sorger reports that local law enforcement pulled him over on the streets several times—but just out of curiosity and appreciation. Marc was impressed that one officer knew enough to think the car was one of the FR500 series builds, and thus checked for a legitimate VIN. He found it, of course!

“During the first few years I owned the Mustang, I used it as a street/strip car and eventually worked it into the high 9s on pump gas,” he said. “In late 2011, I decided I wanted to turn with it, and began building it for IRDC Conference racing and NASA American Iron Extreme.”

Work occurred after hours at Marc’s place of employment, TMS Performance in Auburn, Washington, where he’s general manager and jack of all trades. Initially the engine remained pretty well as it had been for straight-line duty. The 4.6 had been built by TMS a couple years earlier, and sported all forged internals, and an intercooled centrifugal blower pullied for as much as 20 pounds of boost.

“During the summer of 2012 I had a lot of fun running the car at track days, but found the supercharged 4.6 to not be the best arrangement for long periods of wide-open throttle. I had a lot of trouble keeping the coolant temp in check, partly because of the big intercooler physically mounting in front of a big radiator, partly because of the heat endemic to centrifugals.”

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Marc found that as coolant temps increased, the computer pulled timing, in turn raising cylinder temps and coolant temps—in other words, a viscious circle. “I could’ve prevented the computer from pulling timing, but that would’ve lead to detonation. I also could’ve helped matters a ton by backing off on the boost with a larger pulley, but I have a hard time taking horsepower off the table, even when it’s the right thing to do. I guess I’ve got a problem.”

At least there was a solution to Marc’s problem that amounted to little more than money and hard work. As you know by gazing at our pictures, Marc went with normally aspirated pushrod power—a devolution of sorts. Part of the financial sting was soothed by selling the supercharged Three-Valve, which was replaced by nothing less than a 2003 Nextel Cup NASCAR 358 from Roush Yates Engines.

“It’s ironic,” chuckled Marc. “Most people want to put a newer engine in an older chassis, and I wanted to put an older engine in a newer chassis.”

Certainly Marc’s solution isn’t a first in the Mustang world, but it has become a lot less common compared to the days of commonplace 351 and 460 swaps into Fox Mustangs, and it gets our attention. The rarity of such events is a clear indicator of how good we have it today. However, some things from the past have stood the test of time. That’s what we’d say about Ford’s canted-valve small-block, whose original genesis came in the form of the ’69 Boss 302 and ’70 351 Cleveland.

Bud Moore was the first to work with the latter engine in NASCAR in the early ’70s, but Cleveland Fords have proven their worth time and time again over the last forty years. In the mid-to-late ’80s—long before Marc’s ’03 Nextel Cup engine—a hybrid of sorts became the standard build by fitting Cleveland-style heads to 351 Windsor architecture blocks. Some call it a Clevor. That arrangement was what all big Ford teams were using prior to the 2009 switch to the non- production FR9 engine now used in NASCAR. But we digress.

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After getting the engine from Roush Yates, Marc tore it down for inspection and replaced the flat-tappet cam with a big solid-roller. He also fabbed up his own triple-step headers to mate with the fabulous Yates C3s, routed spent fumes out the sides, and moved the fuel tank rearward to provide adequate space.

Topped with a 950-cfm carb from Quick Fuel Technology, the 358-incher just crested 800 flywheel horse-power at a raucous 8,500-rpm wail. To say the least, it’s a sound you don’t hear coming from a S197 every day!

In the car, the new engine is proving to be everything Marc was hoping for—big time power that will repeat all day long. That’s the on-track report anyway. As for on the road, those days for this former street car are pretty well over, even though Marc reports the car is still licensed and he’s made a few freeway jaunts to nearby Pacific Raceways.

“With the blown 4.6, it was docile in street traffic and I’d drive it to work from time to time. Now it idles at 2,200 rpm, the triple-disc clutch is a bit of a chore on takeoff, and I’d be in trouble if I got stuck in traffic.”

Yes, we’d call the conversion to full-race status complete. While a true competitive debut has yet to occur, Marc is enthused by the potential of AIX coming to the Pacific Northwest in 2014. It’s time to play ball.

This ’08 GT is covered in a factory white wrapper, but it’s hardly subtle. Prior to installation of the full-race 358, owner Marc Sorger reports that local law enforcement pulled him over on the streets several times—but just out of curiosity and appreciation. Marc was impressed that one officer knew enough to think the car was one of the FR500 series builds, and thus checked for a legitimate VIN. He found it, of course!


Tech Specs: 2008 Mustang Gt

ENGINE AND DRIVETRAIN

Block

Ford Racing 351

Crankshaft

Bryant billet steel

Rods

Carrillo

Pistons

BME forged w/Total Seal rings

Camshaft

Crane solid-roller w/ 268/280 duration at 0.050-in and 0.803-in lift

Cylinder heads

Yates C3, ported w/ T&D 1.9 shaft rollers

Intake manifold

Ford Racing X351

Fuel system

Custom TMS fuel cell built from ’70 Mustang tank w/ -10 lines, CV Products mechanical pump, and Quick Fuel 950-cfm carburetor

Exhaust

Custom step headers by Marc Sorger w/ 17⁄8 to 2 to 21⁄8-in primaries, 31⁄2-in merged collectors, 3-in H-pipe, and Borla mufflers, and 3-in side exit

Transmission

Tex Racing T101A w/ Long shifter, QuarterMaster 7.25-in triple-disc clutch, Quartermaster flywheel, and chrome-moly 4-in driveshaft

Rearend

8.8 w/ 3.73 gears, Yukon DuraGrip differential, Yukon 31-spline axles, and Whiteline cover

ELECTRONICS

Ignition

MSD HVC-L w/ Moroso NASCAR distributor

Gauges

Auto Meter

SUSPENSION AND CHASSIS

Front suspension

K-member

APR tubular

A-arms

Stock

Struts

KW competition coilovers, double- adjustable

Springs

KW competition coilovers

Brakes

Baer 14-in w/ six-piston calipers and Hawk pads

Wheels

18x10-in Saleen replicas

Tires

Hoosier R100 295/680R-18 slicks

Rear suspension

Shocks

KW competition coilovers, double-adjustable

Springs

KW competition coilovers

Control Arms

Whiteline w/ Whiteline Watt’s link and Whiteline adjustable sway bar

Brakes

Baer 14-in w/ stock caliper and Hawk pads

Wheels

18x10-in Saleen replicas

Tires

Hoosier R100 295/680R-18 slicks