BALANCING ACT

THERE was a great deal of work involved in balancing the new rotating assembly, which ultimately called for a combination of internal and external balancing.

“The Sonny Bryant crankshaft is designed to spin to 10,500rpm, so it’s small and lightweight, but because it’s so small in the counterweights, it already had a lot of Mallory,” Troy says. “When we came to balance it, because we’d added weight with the conrods, the balancing factor became a massive issue.

“Every counterweight already had four slugs of Mallory, so potentially you have a $5000-$6000 crankshaft with about $3000 worth of Mallory metal already in it, and when we went to balance it we really struggled.

“We could not make the engine fully internally balanced because we couldn’t get enough weight in there, and we had to somewhat externally balance it. Where we needed to remove weight we couldn’t, because there was none to remove. And where we wanted to add weight we couldn’t, because it already had Mallory in there.

“We actually had to make an offset counterweight that bolted on to the balancer, and we’ve had to do the same on the flywheel as well, so it’s a combination of both just to get it right. We couldn’t go to a new crankshaft, because the counterweight clearance to the bottom of the piston wouldn’t have worked either. It messed with everyone’s heads trying to get it right, but in the end it was [Wayne] Newby to the rescue, who machined up the counterweight for me.”

The Jesel roller lifters feature a keyway that prevents them rotating in the lifter bores. All these little things count at 10,500rpm The cavernous intake ports are Cnc-machined and beautifully finished. As Troy points out, an engine is nothing but a...