The guys over at Granatelli Motorsports have recently released their in-house designed ignition coils for all late model LT1 and LT4 GM engines. We spoke with Joe Granatelli himself for some insight on their new coil and what it offers the LT1/4 market. Joe tells us that the OEM design, although robust, still falls short in high performance applications. The OEM coils are designed with an intended use of 27,000 volts and begin to fade or become inconsistent under normal operating conditions.
This became evident when a N/A test car that received the new coils picked up a 7 hp gain on coil swap alone. Having seen how well the N/A engine responded, the team knew that serious gains could be had from a forced induction application like that of the Z06 and more recently CTS-V.
The new coil design from Granatelli operates at 85,000 volts (3 times that of OEM), has the longest spark duration available on the market and as Joe tells us “Is the true secret to making power.” The massive amounts of power reduce chances of heat soak, improves durability and consistency of spark. The biggest benefits are cleaner hotter spark which translates to more torque and horsepower. This speaks volumes for the racer who wants absolutely all of the power their setup can deliver.
Joe tells us, that it’s not uncommon for a dyno tuner or the typical friend of friend to exclaim that ignition coils aren’t needed. Who usually has a story that “XYZ” person made over 1,000 horsepower on the stock coils and never appeared to have an issue. He says “Yes these setups do exist and yes these people can make this power on stock ignition,however, you still have room for more efficiency and just because it works doesn’t mean it’s great.”
“Think of it as buying a burger from a fast food joint versus a nice restaurant, [simply put] not all burgers are created equal,” he continued. There are also companion wires available with an impressive .001 ohm drop for every 12 inches. This is, as Joe tells us, practically immeasurable and well below any comparable wire on the market.
Recently Granatelli tested these new coils and their companion wires on their in house 2016 CTS-V. The car baselined at 566 hp and 584 lb-ft. Before the second run the new Granatelli coils and wires were installed for new best of 576 hp and 618 lb-ft.
That’s a 10 hp and 35 lb-ft gain over stock with just coils and wires alone. Joe also noted that contrary to popular YouTube belief, the car used in the promotional dyno video was brand new with less than 200 miles on the car. He said, “It’s clear that a much higher mileage could have skewed numbers due to mileage having taken a tole on the stock parts.“ He assured us that the numbers in the video are 100% true to the claim over stock OEM new parts. We look forward to seeing more of Joe and the guys at Granatelli in the future.