First power steering tester reveals more than you might wish to know

By Titus Bloom It’s common knowledge that the entry of one foreign particle in the power steering system can damage the pump. Even if the pump survives the ordeal the refuse will momentarily zap engine power each time it passes through the rotor housing easily consuming 10hp, according to KRC’s new and unique steering pump tester. “This custom-made machine records horsepower, flow and pressure and checks the data every 1,000rpm from 1,000 to 10,000rpm,” says KRC chief Ken Roper. “It even produces graphs and retrieves information we didn’t request! But perhaps its most valuable attribute is that it reveals information we never knew before, like power consumption under load, and it validates everything.” Though the average Sportsman race team may not be too concerned if a steering pump consumes 3hp or 6hp, others like NASCAR teams cannot afford any power-robbing deficiencies and would eagerly welcome even a ½ hp advantage. What caused recent power steering system failures? Recently new short track oval race chassis have suffered a spate of power steering failures. The troubles were traced to the pressure relief valve (spool valve) in the power steering pump. Apparently, galling had caused it to jam in the bore. “For years,” says Roper, “production road car pumps have been modified and offered for use on new race car chassis. As you’d expect, they are inexpensive and most of the time they perform adequately. But they have always been a marginal proposition for race cars as most of their internals are uncoated. Without exception, any friction in the pressure relief valve area slows steering response.” To maintain the valve’s proper function... read more

Of five major threats to a clutch system, what would you consider the most forbidding?

Archie Bosman: As you sit quietly reading these lines, a whirl of activity is taking place in the bell housing. Let’s imagine for a moment the clutch assembly could express its greatest anxiety, what might it be? Might it be the use of excessively harsh friction compounds on the clutch discs or inadequate clamping forces causing slippage? Perhaps, extremely sticky tires are the main threat? Enumerating the cardinal sins: Apparently ‘no’, according to Ram Clutches none of these represent its greatest fear…its principal concern would be mass—that is the weight of the car carried into motion by the clutch. A heavier vehicle imposes a greater load on the clutch system than a lighter one. Further perils include poor gearing, improper flywheel mass and, indeed, sticky tires. A high performance car with an inadvisably high rear-gear requires more manipulating of the clutch pedal to prevent it from slipping than one with a lower gear. A higher first gear (lower numerically) is also problematic as it, too, imposes a greater load on takeoff and, furthermore, can be detrimental to the clutch even when it is fully engaged. Linked closely with high first-gear ratio deficiencies is the flywheel. The purpose of the flywheel is to create inertia, which refers to preserving a state of uniform motion that helps to get the car moving. A heavier flywheel generates more inertia and thus makes it easier to accelerate from standstill. It also reduces clutch slipping on takeoff. On the other hand, with a properly geared vehicle, that is one with an appropriately low gear that invites the use of a light flywheel, it will... read more

Putting the Squeeze on

The Importance of Compression Ratios and How to Measure Them: Since race pistons in domestic V-8 engines move up and down in excess of 100 times per second, replacing them is a normal part of a racer’s routine. NHRA Top Fuel and Funny car teams replace them after every race pass and every second qualifying pass. Pro Stock teams replace them after every 40 passes approximately, and weekend warriors replace them every 12 to 18 months, sooner if their engines are nitrous-assisted. Read the complete story as it appeared in Maximum Drive magazine’s 2015 Sept/Oct... read more

2015 Mustang upgrade: the trouble with supercharging

By Sam Logan: Adrian Gomez, an industrious 27-year old who manages Mak Performance, a Miami specialty shop established in 1995, bought a 2015 Mustang 5.0 and with fewer than 7,000 miles on the clock installed a Pro Charger centrifugal supercharger. It extended the Mustang’s power output at the rear wheels from 376hp to 600hp, an impressive 60 percent improvement. With one of the two vital ingredients in place—225 additional horsepower—he decided that instead of fulfilling the role as a drag race spectator at the NMRA season opener at Bradenton, he would present himself as an entrant in the True Street class. This leads us to the second vital ingredient—the clutch. Doubtless it was tempting to ascertain just how long the original factory clutch might support the additional horsepower…and it didn’t take long to find out. The car slipped the clutch on the first pass, running an Elapsed Time of 11.97 seconds over the quarter-mile distance and by the third pass it had overheated and was on the road to ruin. Undaunted the intrepid young Gomez limped back to Miami where he would replace the failed clutch system with a twin-disc clutch-flywheel set-up. His objectives were to acquire better friction materials, 2,400psi of clamping force and an easy clutch pedal feel for stop-start traffic conditions. For all of that, there is no intrinsic weakness in the original equipment Mustang’s clutch arrangement. It is just that it was neither designed to transmit 60 percent additional horsepower nor to transmit it via twenty-nine-inch diameter Mickey Thompson Drag Radials. Nonetheless, its street-driving capacity contrasts starkly with Ram’s Force 10.5 dual-disc clutch-flywheel arrangement, which... read more

Basic installation rules from TorqStorm

By Alfie Bilk: Fuel pump requirements for carbureted systems must be capable of supplying proper amount of fuel at maximum operating pressure. To obtain maximum fuel pressure required under boost, add idle fuel pressure to maximum boost pressure.  Read condensed details below.   Basic forced-induction guidelines (6-10psi boost range) for carbureted systems   1.Forged pistons preferred for all boosted applications 2. Cast or Hypereutectic pistons may be used below 500hp and low-boost applications 3. Compression ratios of 9.1 to 9.5:1 ideal for boost levels of 6-8psi on 91-93 octane pump fuel 4. Use lobe separation angle of 112 to 116 degrees, split pattern works best 5. Fuel pump requirements for carbureted systems must be capable of supplying proper amount of fuel at maximum operating pressure. To obtain maximum fuel pressure required under boost, add idle fuel pressure to maximum boost pressure. (If your idle setting is 8psi and your maximum boost is 8psi your maximum fuel pressure required is 16psi) 6. Use a blow-through carburetor. TorqStorm offers custom billet blow-through carburetors sized per application. Contact TorqStorm direct for carburetor specs and pricing. 7. Must use carbureted boost-reference fuel pressure regulator with a 1:1 rise ratio 8. Headers recommended for maximum performance 9. Will work with single or dual-plane intake manifolds (more torque generated by dual-plane designs) 10. Ignition control recommended with adjustable boost-timing retard to prevent detonation. (MSD BTM part number 6462)   Information furnished by Torqstorm® Billet Superchargers 2909 Buchanan Ave. SW Wyoming, MI 49548 Office 616-226-9476, Mobile 616-706-5580... read more

Ovality and other guarded racing piston shapes

By Titus Bloom: Gibtec, makers of custom billet competition pistons reveals… Below their ring lands, pistons are neither round nor do they have parallel sides. Instead they have a larger diameter towards the bottom, between the base of the piston and the piston pin hole. They become progressively smaller toward the top of the piston, which is round because, to achieve proper sealing, round rings operate in round cylinders . The smaller diameter piston crown allows for greater expansion in a region closest to the heat source. Ovality, which means out of roundness, is necessary in all pistons to allow for thermal expansion. It also compensates for deflection of the piston skirt caused by side loads. Pistons are manufactured with single, double or triple ovality and the ovality is best measured by a precision roundness form measuring machine. Ovality in simple terms means the piston is narrower along the piston pin axis (the minor axis) than the thrust axis (the major axis). Because ovality is a function of heat, and therefore the growth the piston is likely to encounter, it is the amount of ovality assigned to a piston that’s the clever part. Ovality values differ, depending upon whether the engine is naturally aspirated, supercharged, turbocharged, or charged with nitrous oxide. Obviously, heat, cylinder pressures and side loadings are much less in the naturally aspirated engine and hence less piston ovality is required. Correct ovality usually manifests itself in the form of a bearing area. This is the area in the middle of the piston skirts that rides in the cylinder and it’s surrounded by a boundary of piston... read more

Impressive diesel gains: 2.1lb weight-saving per cylinder

Irvine, CA: At CP-Carrillo, two hybrid combinations are in the final stages of testing. One is designated for the common rail 5.9 liter Cummins using a Duramax pin size and compression height with a rod length of 0.856in longer than stock. The other combo is developed for the 6.6 liter Duramax, which comprises a long-rod diesel arrangement with a Top Fuel piston pin. The connecting rod is 0.202in longer than stock. The weight saving is not yet known on the Duramax combination, but news of an impressive 2.0lb approximate saving per cylinder has emerged for the Cummins. Though prototypes are already in use in Truck Pulling contests, CP-Carrillo’s long-rod combinations were initiated for drag racing. Company’s Rick Canning said that with the right camshaft installed the Cummins diesel will rev to 6,500rpm on the snap-of-a-finger. “It’s easily achieved,” he says, “when there is significantly less reciprocating mass attached to the crank!” The test Cummins, which was dynoed with a stock camshaft, generated 1,000hp @ 3,200rpm and produced 1,500lb ft of torque. What happens next? Apparently, the engine is to be re-cammed and installed in a truck puller. When CP-Carrillo created the new Cummins hybrid connecting rod 0.856in longer than the stock counterpart and incorporated a Duramax pin size, a reduction in pin diameter resulted: from 1.575in to 1.358in. The new pin is also shorter. The compression height is also changed from a stock Cummins to Duramax, which measures 1.946in. The difference between the Cummins compression height with the pin change is 0.856in. This instigated the longer connecting rod, which improved the rod-to-stroke ratio by reducing the side load on... read more

Cure for uncomfortably high clutch pedal on late-model street cars

By Sam Logan: Most late-model street vehicles use an internal hydraulic clutch release bearing, sometimes called a concentric slave cylinder (CSC). Yet, unfathomably, many of them suffer from clutch engagement high on the pedal travel. For most drivers, this is not comfortable. Conveniently, Ram Clutches has introduced a pedal-height adjuster, which is situated inline between the hydraulic master cylinder and the slave cylinder. It is in effect, an accumulator in which a piston and spring are housed. When the adjustment screw is turned in to its fullest extent, the piston cannot move and the adjuster is bypassed. In fact, this is the condition in which the system should be re-bled. As the adjustment screw is turned out and the pedal depressed, the fluid flows into the adjuster and pushes the piston back. Once the cylinder is full, the remaining fluid is routed to the hydraulic bearing. This essentially introduces free-play to the pedal travel and lowers the point where the clutch engages, allowing the driver to adjust the pedal to the most comfortable driving position. A lower pedal also quickens clutch response. A bonus feature of this adjuster is its ability to control the travel distance of the release bearing. This prevents over-travel of the clutch fingers, which can lead to clutch malfunction at higher engine RPM. Applying the pedal-height adjuster’s resourcefulness to the competition clutch Also worth noting, original equipment manufacturers use pre-loaded release bearings that are in constant contact with the clutch’s diaphragm fingers while competition-style bearing makers do not. By contrast they seek maximum clutch clamping force and, therefore, require some free-play between the clutch release... read more

CP-Carrillo: X-style pistons for power-adder engines

Irvine, CA: CP-Carrillo is introducing a new X-Style series of pistons for power-adder engines. Available for Top Alcohol Hemi applications with plus or minus 4.467in bores and Hemi canted valve for Pro Mod with plus-or-minus 5.000in bores, these pistons include several advanced features including the ability to run narrower rods and shorter pins, often resulting in reduced weight for most applications. BUILT TO LAST Manufactured from 2618 T-61 alloy, these pistons utilize an “X” forging for added structural support and durability. In addition, they can be designed with buttons or with wire locks and include vertical or lateral gas ports as well as forced pin oiling. OTHER TECHNICAL ELEMENTS Developed through rigorous testing and R&D – including recent wins in all the alcohol classes – the X series is available for IMMEDIATE delivery and suits most popular Dragster, Funny Car, and Pro Mod-type applications. DROP-IN READY Join the winning race teams that have chosen CP-Carrillo pistons and rods, and get them off the shelf! CP-Carrillo’s X-style pistons are ready to drop in to an engine and should improve horsepower and durability out of the box.   BACKGROUND CP-Carrillo is a company totally dedicated to pistons and connecting rods. Experienced sales specialists provide unique piston and rod solutions for myriad engine applications. The company continuously endeavors to combine manufacturing excellence, product guidance, and ongoing technical support to effectively address customers’ needs.   For more company information please review our website: CP-Carrillo is a member of PANKL Racing Systems. Contact: CP-Carrillo 1902 McGaw Irvine, CA 92614 949-567-9000 phone 949-567-9010 fax... read more