Inside story

By Alfie Bilk: 

Early in the winter of 2015, Pace Performance of Boardman, Ohio, initiated a dyno test to ascertain the merits of the TorqStorm supercharger. Keen to learn how it would perform against a known rival, they promptly dispatched a 383cid small-block Chevrolet to the premises of Lamar Walden Automotive in Doraville, Georgia.

A new structure with dynamic looks, the Torqstorm was designed for stock or mildly tuned engines. It generates 6-8psi boost, averages 40 percent power increase over base and supports 700-plus hp.

Designed for stock to mildly tuned engines, this TorqStorm generates 6-8 lbs psi supercharge boost and averages 40 percent power increase over base, supporting 700-plus horsepower.

The 383 was a crate engine from BluePrint Engines and its part number, BP38316CT1, indicated the unit was specifically designed for power-adders.

09 (4147)Lr

“This supercharger possesses the kind of torque spread and throttle response no turbo alternative is likely to match” – Rob Walden

Over at Lamar Walden’s, the 383 with a 750cfm Demon Blow-through carburetor is attached to the dyno. A crankshaft drive pulley and spacer are attached to the harmonic damper. Then the ¾-inch-thick TorqStorm billet bracket is installed on the left cylinder head with three accompanying spacers and a backing plate. The supercharger is secured to its robust bracket by seven socket head bolts.

And then there’s the 8-rib serpentine belt, which is fitted and tensioned by a simple hand-adjusted idler. Thereafter, a small-bore hose is connected between the boost-reference port on the blow-off valve and the carburetor.

To apply belt tension to the crank and gearbox pulleys a simple self-adjusting idler wheel is moved downward.

On earlier systems, belt tension on crank and gearbox pulleys was accomplished by a simple idler wheel.

All that remains is to install the hat or bonnet on the carburetor and to connect it to the supercharger with the two large-bore discharge tubes supplied with the kit. Positioned between the discharge tubes is the inline blow-off valve, and tightening the 4 stainless steel hose clamps completes the arrangement.

Vacuum-controlled blow-off valve serves two purposes. It allows boost to occur only above light throttle when vacuum falls to a pre-set level. Second, it releases excess boost to prevent damage to the system should the throttle abruptly close on deceleration.

Vacuum-controlled blow-off valve serves two purposes. It allows boost to occur only above light throttle when vacuum falls to a pre-set level. Second, it releases excess boost to prevent damage to the system should the throttle abruptly close on deceleration.

In the dynamometer room, stood Rob Walden, who has been supervising and testing high-performance and competition engines and engine parts for 25 years. The tests would include, first, confirming the power output of the naturally aspirated BluePrint 383 engine. Second, they would assess the TorqStorm supercharger and, third, repeat the process with a Vortech unit.

Earlier, the BluePrint small-block sustained two days of comparison tests. The directive from Pace Performance also included exhaustive trials with supercharged EFI units—none of which, by the way, matched the performance of the blow-through carburetor.

Supercharged engines generate higher combustion temperatures and therefore run spark plugs that are one or two steps colder to deter detonation—depending upon the amount of boost employed.

Supercharged engines generate higher combustion temperatures and therefore run spark plugs that are one or two steps colder to deter detonation—depending upon the amount of boost employed.

It’s worth bearing in mind the fuel requirements for the boost condition as Walden reminded us: “Idle and cruise conditions don’t alter fuel consumption appreciably,” he says, “but boost conditions do. Also it’s important the spark plugs operate in the correct heat range.”

Commonly, supercharged engines run higher combustion temperatures than their naturally aspirated counterparts. Thus, spark plugs are usually one or two steps colder for the former to deter detonation, depending upon the amount of boost.

As you might expect, the dynamometer preparations for the tests were routine: crank-up the engine and allow it to reach normal operating temperatures—coolant around 180 degrees Fahrenheit, lubricating oil over 100 degrees and ignition timing checked, which had been set to 32 degree total.

After the first dyno pull, the spark plugs were removed for visual checking. For testers adept in spark plug reading, old habits are hard to break. Accurate spark plug readings indicate how the air-fuel mixture is burning in each cylinder, a handy skill to hold in reserve, especially when a problem arises and quick, empiric information is needed.

The Vortech performed with gusto but it was the early power delivery from the TorqStorm that brought out the most admirable quality.

The Vortech performed with gusto but it was the early power delivery from the TorqStorm that revealed its most admirable quality.

Inevitably, the dyno tests began by confirming that the 383 BluePrint small-block breathing at atmospheric pressure made 436hp and 460lb ft torque at 4300rpm. But when the TorqStorm was added it generated 627hp—an improvement of 191hp—with 566lb ft torque at 5800rpm and showing a flat curve on the graph. Though the Vortech generated a promising 620hp at 6,000rpm, its best torque delivery measured 546lb ft.

TorqStormDynoTest1

When the TorqStorm was added it generated 627hp—an improvement of 191hp—with 566lb ft torque at 5800rpm

VortechDynoTest1

The Vortech generated a promising 620hp at 6,000rpm, its best torque delivery measured 546lb ft

 

 

 

 

 

 

 

 

 

But the best part was the TorqStorm’s ability to generate 400lb ft torque at 2,000rpm; its rival reached 400lb ft at 2,500rpm. At 3,000rpm the ‘Storm generated 484lb ft compared to the Vortech at 436 and as engine speeds increased the deficits slowly diminished to around 10lb ft at 5800rpm. Nonetheless, these were the auspicious symbols of an interesting comparison.

This gearbox with its self-contained oil reservoir, straight-cut gears and ceramic bearings, drives the compressor wheel to speeds in excess of 70,000rpm.

This gearbox with its self-contained oil reservoir, straight-cut gears and ceramic bearings, drives the compressor wheel to speeds in excess of 70,000rpm.

Compressor wheel comprises 16 blades; eight main blades with eight shorter splitter blades. Their advance design introduces boost to the engine from 1,850 to 6,500rpm.

Compressor wheel comprises 16 blades; eight main blades with eight shorter splitter blades. Their advance design introduces boost to the engine from 1,850 to 6,500rpm.

Air intake: Spinning at high speeds, the clearance between the compressor wheel’s complex curved edges and the compressor cover’s contours measures 0.022 to 0.024in when cold.

Air intake: Spinning at high speeds, the clearance between the compressor wheel’s complex curved edges and the compressor cover’s contours measures 0.022 to 0.024in when cold.

Via the 8-rib serpentine belt, power is directed from an 8in crank pulley to this 3.250in gearbox pulley. Inside, a large diameter gear meshes with a smaller gear whose shaft spins the compressor wheel situated in the intake port.

Via the 8-rib serpentine belt, power is directed from an 8in crank pulley to this 3.250in gearbox pulley. Inside, a large diameter gear meshes with a smaller gear whose shaft spins the compressor wheel situated in the intake port.

Inside the TorqStorm gearbox, the tolerance between the two shaft centers measures 0.0002in. This chamber possesses its own dedicated oil supply and the inner perimeter O-ring seals the gearbox body to its cover.

Inside the TorqStorm gearbox, the tolerance between the two shaft centers measures 0.0002in. This chamber possesses its own dedicated oil supply and the inner perimeter O-ring seals the gearbox body to its cover.

TorqStorm finishes their superchargers in natural alloy, black anodized or micro-polished and if someone were to ask me to name the single cleverest aspect of their new charger, I’d point not to the rigidity of its billet construction or the superiority of its ceramic bearings. I’d bypass the design mastery of its compressor wheel and its wide boost range, too, and point instead to its pricing: $2,800.

 

Sources

TorqStorm Superchargers
Grand Rapids, Michigan
(616) 706-5580
Sales@TorqStorm.com
www.torqstorm.com

 

Pace Performance
Boardman, Ohio
(888) 748-4655
Parts@PacePerformance.com
www.paceperformance.com

 

BluePrint Engines
Kearney, Nebraska
(800) 483-4263
info@blueprintengines.com
www.blueprintengines.com

 

Lamar Walden Automotive
Doraville, Georgia.
(770) 449.0315
lwarob@gmail.com
www.lwaengines.com