HELD TO FIVE-TENTHS OF ONE THOUSANTH’S INCH, LUNATI REVEALS NEW SIGNATURE SERIES I-BEAM CONNECTING RODS

Written by Moore Good Ink Olive Branch, MS: Lunati has taken the wraps off its all-new 4340 alloy steel Signature series connecting rods. As direct replacements for their successful FM (fully machined) Series, these new race-ready I-beam forgings are 100 percent sonic tested and Magnaflux inspected. In addition, they are manufactured to extremely close tolerances (.0005in between centers), weight-matched to plus-or-minus 1 gram, and heat treated to 28-30 on the Rockwell C scale. They are made to the most precise standards Lunati knows, and are available in sizes from 5.4in to 6.4in. Precision-machined and with close attention to detail these aircraft-quality mill-certified connecting rods are ideal for use in circle track, drag race, off road or marine applications. Indeed, they suit all naturally aspirated and forced-induction engines that are subjected to high engine speeds and stresses. Lunati, a specialist in competition connecting rods for over 20 years and a supplier to the NASCAR scene for the past five, has successfully tested the new Signature series in NASCAR competition during the course of the past year. Derek Scott, head of the Mississippi-based camshaft and components firm, said the success of their existing FM series over the past decade meant “we have hardly changed the rod’s material properties, but full sonic testing has been hugely significant, guaranteeing increased strength and eliminating risks of internal impurities-plus the rod’s precise tolerances are exceptional.” Commonly, sets of connecting rods can vary in their center-to-center dimension by up to .004in. For 2.100in and 2.000in crankpins the Signature series connecting rods are supplied with 7/16in bolts; for smaller 1.889in crankpins (Honda journal) 3/8in bolts are provided....

LUNATI’S NEW SIGNATURE SERIES I-BEAM CONNECTING ROD: HOW IT’S MADE

Last Friday evening the How It’s Made TV program on the Science Channel featured Lunati cams and crankshafts. Four hours earlier a forging plant in Michigan was engaged in the making of Lunati’s new Signature series connecting rods. First they cut lengths of 1-7/8in diameter 4340 round bar and convey them to an induction-heater, which raises their temperature to almost 2,300 degrees F. In a malleable, plastic condition, not a molten state, the material is handled by tongs and drawn through rollers to flatten it. Then it is placed in each of three con rod impressions carved into a die block. As the hammerman runs the hammer, he displaces the soft, white hot metal into each impression, gradually forming the connecting rod. The force of the 4,000lb falling hammer impacts the material one strike per second. Three strikes of the hammer and the connecting rod is...

LUNATI'S NEW SIGNATURE SERIES I-BEAM CONNECTING ROD: HOW IT'S MADE

Last Friday evening the How It’s Made TV program on the Science Channel featured Lunati cams and crankshafts. Four hours earlier a forging plant in Michigan was engaged in the making of Lunati’s new Signature series connecting rods. First they cut lengths of 1-7/8in diameter 4340 round bar and convey them to an induction-heater, which raises their temperature to almost 2,300 degrees F. In a malleable, plastic condition, not a molten state, the material is handled by tongs and drawn through rollers to flatten it. Then it is placed in each of three con rod impressions carved into a die block. As the hammerman runs the hammer, he displaces the soft, white hot metal into each impression, gradually forming the connecting rod. The force of the 4,000lb falling hammer impacts the material one strike per second. Three strikes of the hammer and the connecting rod is...

"If it doesn't live on the dyno pull it won't live on the salt"

Written by Moore Good Ink On its last visit to Bonneville, Duttweiler’s record-holding 300cu inch turbocharged small block ran 436mph in the Poteet & Main Speed Demon. “The advantage of Diamond pistons at high boost pressures,” said Ken Duttweiler, “is they don’t crack or bend-they are free of deflection concerns.” Earlier the astute Duttweiler had created a program that enables their dynamometer to assimilate four- to five-mile Bonneville passes at speeds in excess of 400mph. They run it up from 6,000 to 8,500rpm, assimilating each gear change, and when they reach full throttle in 5th gear with 30lb of boost the dyno runs for a further 1min and 10sec with power output at 1,900hp and an exhaust system glowing bright white hot. Says Diamond advocate Duttweiler, “If it doesn’t live on the dyno pull it won’t live on the...