The curse of the round wire lock

By Bertie Scott Brown, January 28, 2015   When a round wire lock, the spring-loaded device that retains the piston pin within the pin towers, comes out while the engine is racing, it releases a fanatical frenzy, a chain of events that most engine builders describe as catastrophic. It is an insecurity within the racing engine most dare not think of. Recently, however, a Californian engineer shook the establishment, when he not only cured the curse but also devised an ingeniously simple method of installing and removing them. Karl Ramm, who has been engineering racing pistons for almost twenty years, has devised a new style of wire lock: the Kramm-Lox®. Characterized by its 90 degree tang, which resides within the existing pick lock notch, the Kramm-Lox importantly will not spin. Equally appealing, this non-rotating lock requires no modifications to the traditional piston. Furthermore, Ramm was also the inspiration behind a tool (Patent Pending) that makes them easy to install and remove. Also worth noting, the tool negates the danger of scratching the pin bore; it also removes the threat of eye injury, a comforting distinction from the notorious, flying spring-loaded locks! In addition, by keeping the wire lock stationary in the pin bore groove, Kramm-Lox avoid other self-destructive traits. If the traditional round wire lock rotates placing its gap at the top of the pin bore, particularly in high-revving long-stroke engines, the lock can distort and can pop out. The extreme jolt that occurs as the piston changes direction at the top of its stroke can momentarily change the shape of the lock. “I just started using Kramm-Lox,”... read more

Nitrous: the race tuner’s biggest challenge

By Fergus Ogilvy, February 4, 2015 Starting a competition piston company in the second decade of this century could be a bleak proposition. Finding new customers isn’t easy. Engine builders have a stubborn tendency to remain faithful to their existing suppliers, unless something goes awry. You could play the game grimly and die of ulcers or you could play it with a light heart and dedication and perhaps survive without losing sleep. Gibtec Pistons, the Denver-based operation did exactly this. But they had one other valuable resource to rely upon: decades of experience at the competitive edge, including several ten-year development programs with NHRA Pro Stock teams But when asked where they see the biggest challenges in race engine tuning, company founder, Robbie Giebas, responds with one word: Nitrous!  Why so? “Well, the top tuners will tell you nitrous engines have never been completely mastered—there’s still an element of mystery about them. Nitrous oxide induction requires a totally different approach, and it’s a volatile science; if the tune-up is off a little, parts need replacing. “Unlike the turbo or blower guys, who might get fifty or sixty runs from their pistons, when those nitrous guys are really pushing hard they’re replacing rings every three or four runs—it resembles the Top Fuel class in many ways. If they ease off a little on the tune-up they’ll become uncompetitive. And when the racing gets close, they’ll routinely dismantle the engine after every pass. Leak-down tests, ring end-gap checks, raised ring lands, pinched rings these are constant topics in their world.” What provokes a raised ring land or a pinched ring? “Race... read more

Hydraulic release bearings: operating with the correct gap.

By Alfie Bilk, December 5, 2014 Unlike OEM clutch release bearing mechanisms that operate in constant contact with the clutch diaphragm fingers, high-performance aftermarket release bearings function only when the clutch pedal is depressed. Typically, these release bearings operate with 0.800in of potential travel. But more importantly they must be positioned with the correct gap when the pedal is not depressed; that is, the gap between the contact face of the release bearing and the clutch fingers. Excessive gap causes improper release; inadequate gap can cause the bearing to over-travel and collide with the snap ring or encounter slippage as the clutch wears and the fingers move back, making contact with the bearing. Single-disc clutches operate best with a gap of 0.150in while dual-disc sets require a gap of around 0.200in. Because the clutch fingers automatically travel toward the release bearing as the friction disc/s wear, an additional clearance of 0.050in is assigned to the dual-disc arrangement. Click to enlarge illustration. To establish the correct position of the release bearing on the input shaft, these measurements are required. Click here to access them: or to watch the video click here. Source: Ram Clutches Columbia,  SC 29203 (803) 788-6034 read more

Key changes in high-performance diesel pistons

Written by Alfie Bilk September 8, 2014 Mentor, Ohio: Wiseco, the eminent high-performance piston maker established in 1941, is launching a new range of diesel pistons for Dodge Cummins, GM Duramax and Ford Power Stroke engines. Using technology that should make a significant impact in the diesel performance world, the first two piston designs are devoted to Cummins 5.9 liter 12- and 24-valve engines and GM Duramax power units. These will be followed by new designs for Cummins 6.7 liter as well as various Ford Power Stroke models. The chief concern with cast aluminum factory pistons on high-performance diesel engines generating 850 to 1,000hp in street trim, and higher in truck-pulling and diesel drag racing, is premature failure. Alternatively, the shortcoming in high-output diesel engines with standard forged aluminum pistons can be soft, short-lived ring grooves. Wiseco’s solution is Armor Plate™. To the pistons’ most highly stressed areas—chiefly to the bowl, pin bores and ring grooves—Armor Plate adds hardness. In addition, engine building costs are eased, particularly the balancing process, by maintaining piston weights close to those of the original equipment units. Just as impressive is how Wiseco set about creating these new designs, collaborating with specialists in high-level competition. Adept at extracting the utmost from current diesel technology, Wiseco coupled their insight with their own piston-making expertise, which triggered studies of injector patterns and advanced bowl designs. The studies also brought remarkable weight savings for engines with internally balanced crankshafts. Custom units distinguish themselves with weights in the low 600g range, resulting in 30 percent net loss in piston mass, which prolongs crankshaft life by reducing twisting forces.... read more

How a clever pump design saves 4 to 6hp

Tumultuous change? Maybe not but KRC has uncovered significant power losses with unique new test equipment By Freddie Heaney, August 1, 2014, Photography Moore Good Ink Kennesaw, GA: Recently, Chant, the engineering authority in electronic-hydraulic control systems, delivered new testing equipment to KRC, the engine pulley and power steering specialists. Strikingly, the tester, the first of its kind, has uncovered power steering system secrets reminiscent of aerodynamic revelations found in a wind tunnel. A sophisticated one-off machine, it reveals that as engine speed increases in 1,000rpm increments one power steering pump can consume twice the power of another. [See Consumption tables at end of article.] The news, a defining moment for some, could contribute a decisive edge to not only NASCAR race teams who cherish every part of a horsepower gain but also to road race teams and short track oval racers. Surprisingly, the tester further confirms that a small 5.9cc pump is capable of developing as much flow as a bigger pump while consuming half the horsepower. During recent tests with several GM-style power steering pumps modified for competition, the tester demonstrated they absorb around 3.6hp at 8,000rpm engine speed. By comparison KRC’s Pro Series 5.9cc pump used on Aston Martin’s victorious Le Mans sportscars absorbs 1.9hp. All pumps were tested with 125psi of load applied, which is the average pressure generated in a power steering system when operating in the straight ahead position. Using data acquisition and a GoPro camera to identify power loses Beyond this the tester not only measures pressure and flow and calculates power consumption but also duplicates the data acquired on a racing... read more

Combine an electrified turbocharger with a battery pack, you’ll scarcely believe the effect!

By Freddie Heaney: If you reduce engine displacement by 50 percent, add an electrified turbocharger and connect it to an on-board battery pack what do you get? Amazingly…the same fast lap times while using 35 percent less fuel—and the elimination of turbo lag! We live in fascinating times. For the 2014 racing season Formula One teams encountered their biggest challenge in decades. Generating toward 800hp, the former naturally aspirated 2.4 liter V8 racing engines, which had been revving to over 20,000rpm and more recently limited to 18,000rpm, were replaced by smaller, turbocharged 1.6 liter 90-degree V6 units accompanied by an on-board battery pack. The battery pack generates a further 160hp and uses an energy recovery system (ERS) to keep the battery charged. Assuredly, the changes have brought an abundance of new technologies in its wake. What was the purpose? These efforts have been devised as an environmental gain by the sport’s ruling body, the FIA, to reduce fuel consumption to 100 kilograms (220lbs) per race. Races are limited to a maximum of 2 hours in duration. Under the new regulations refueling stops are no longer permitted. Miraculously, the new power units can complete a full race distance within seconds of last year’s times while using 35 percent less fuel thanks largely to the ERS. The ERS recharges the battery pack by motor-generators connected to the electrified turbo and to the braking system. The function of the motor-generators is determined by the direction in which the electricity is flowing. If the electricity turns the shaft it functions as a motor. But if the engine spins the shaft it functions as... read more

First off-the-shelf asymmetrical pistons for LS high-performance engines:

By: Sam Logan Particularly effective on forced induction and longer stroke models JE, our largest indigenous racing piston maker, brought a fresh new presence to asymmetrical forged pistons when they began investigating their potential in race engines, particularly high performance forced-induction engines. As you’d expect piston side loads increase with boost pressure—they also increase with longer stroke crankshafts and even aftermarket camshafts. But JE’s asymmetrical piston with differing skirt sizes and off-set pin has presented several interesting solutions.     -Introduces less friction -Reduces piston weight -200 LS configurations in stock -Two-day delivery 95% of the time -Two-week delivery on custom items -Five-day on expedited custom items Irvine California: JE has pioneered a new range of asymmetrical pistons for GM LS engines. Available off-the-shelf, they are the first of their kind. Known as asymmetrical because their skirts are of noticeably different sizes—a thrust side and a non-thrust side that address disproportionate loads in the cylinder. Also, their piston pin is positioned slightly off center. Though designed to support high cylinder pressures in applications producing 1,500hp-plus, both forced induction and nitrous, they also operate happily in naturally aspirated LS engines. Beyond this the piston configuration promotes lightness, strength, and durability as its unique design enables material to be distributed in the areas exposed to higher stresses. The major skirt, which operates on the thrust side, combats the highest side loads. The lowest side loads, in contrast, are handled by the minor skirt, which is free of undue weight and friction. Further weight reductions are achieved with 106-gram piston pins. Measuring 2.250in long these compare favorably with the pins of traditional... read more

Six helpful tips on four-barrel carburetor tuning

1.) How do I select the right size of carburetor?  Carburetor performance is largely based on the air-speed traveling though its venturis. If they are too big the air speed will be reduced, too small and vice-versa. Probably the best instruction on carburetor choice is found in the Demon Carburetor Selection guide. It is based on camshaft duration at 0.050in of valve lift, the type of intake manifold (dual plane or single plane) and the type of transmission (manual or automatic) and stall speed. Beyond this it is always best to discuss carburetor selection with a qualified technician. Click here for the Demon Carburetor Selection Guide.   2.) What is one of the most commonly overlooked carburetor-tuning issues? One of the greatest obstacles faced by amateur carburetor tuners is failing to understand the essentials of initial ignition timing. Ignition timing is affected by a host of elements including fuel type, mixture strength, combustion chamber shape, compression ratio, temperature and humidity. Bigger camshafts and larger cylinder heads with matched intake manifolds require increased ignition timing to promote better air velocity and maintain efficiency. Thus the carburetor is helpless in its plight if the initial timing is late or the timing advance curve is slow. These two potential timing impediments frequently exhibit poorer starting and drivability troubles. The ignition is always timed to fire the spark plug before the piston reaches Top Dead Center (TDC) in the cylinder. Firing before TDC is necessary because of the time it takes for the flame front to ignite the air-fuel mixture in the cylinder. Demon’s carburetor selection guide consists of helpful recommendations on ignition... read more

Competition Connecting Rods – Only the Strong Survive.

By Sam Logan: Nothing undermines the legitimacy of a connecting rod maker more than a deficient batch of rods. He agonizes constantly about heat treatments, high revs, heavy pistons, heavy pins, the number of race laps between rebuilds, but probably most of all whether or not nitrous is being sprayed. It’s a complicated business determining minimum weight while yielding maximum strength, enough to withstand the abuse sustained by the average race motor. Dyer’s Top Rods overcomes these special problems with their connecting rods by forging them in 4340, a very tough material with high nickel and high molybdenum content. In fact, the chemical constituents of the rods are almost identical to the dies from which they are forged. Probably the chief reason they consistently withstand high impact loads at high temperatures is because they are subjected to a special heat treatment, a painstaking process closely governed in a batch furnace. To this end, controlled quenching and elaborate racking procedures maintain the stability of the connecting rods during the procedure.  Though Magnaflux testing (which uses dust in a magnetic field to reveal cracks on the rod’s surface) has been in use for decades, “It was sonic testing that had the most profound effect on the quality of Dyer’s Top Rods,” says company president, Roger Friedman. In use for most of this decade, sonic testing is characterized by a sound wave transmitted through the metal, revealing any hidden internal inclusions. Under high stress conditions, inclusions or ‘cold shuts’ can be fatal to the connecting rod’s longevity. For performance as well as practical and economic reasons, most competition small-block V8 engine builders... read more