Oil's Not WellAfter his first set of dyno flogs, Tom discovered several distressed rod and main bearings. This predicated the addition of a Manley high-volume oil pump and an ARP pump shaft to improve oil flow to the rotating assembly. A stronger oil-pump shaft is critical since small-block Fords are famous for twisting them in two, even on mild small-blocks. A subsequent teardown indicated that even this didn't solve the problem. Tom next added an SVO engine oil restrictor kit and tossed the factory Ford hydraulic rollers in favor of a set of Comp mechanical rollers: "I didn't even want to play the game of seeing how much oil I could restrict with hydraulic lifters." It seems the hydraulic rollers pump much more oil to the top end, starving the rest of the engine. This is mainly due to the fact that the little Windsors are designed to direct oil through the lifters first, then down to the mains and rods. "I wore it out twice before we got that figured out," Tom said.
Rule Number 7 in The Great Book of Camshafts will tell you not to run solid-roller lifters on a hydraulic-roller cam. The fundamental difference comes down to a lack of clearance ramps on the hydraulic-roller cam. Clearance ramps are a gentler lifter rise built into a mechanical-lifter lobe that closes up the 0.018 to 0.020 inch of lash built into all solid lifter camshafts. Tom meditated with his cam guru and dialed in 0.004 inch of hot lash into his valvetrain and has yet to have a problem. But maybe that's because Tom likes living on the edge. "It's definitely noisy. But the purpose of this car is to be noisy and pissed off."
Let The Beatings ContinueSo far we've covered the buildup and dyno sessions. By the time Tom bolted the motor in the car and got as close as low 10s with an automatic, he realized it was time for a manual gearbox. At that point, Tom says, "I had over 80 recorded engine dyno pulls and well over 180 runs altogether on both the engine and chassis dyno, not counting the runs down the dragstrip. That's pretty sick when you think about it!"
There's as much of a story on Tom's trials with traction and pulling off his 10-second dream as the engine buildup, so we'll save all the good drivetrain stuff for next month. Until then, mull over how much those stock cast main caps are moving around at 500 hp at 7,100 rpm!
'Dyno TimeTest 1: The 306ci small-block with 151/48-inch chassis headers and 91-octane pump gas.
Test 2: Same configuration with 131/44-inch headers and VP Ultimate 4 motorcycle race gas that is highly oxygenated. The headers alone made about a 32hp peak increase, while rest of the gains are from the fuel. This is one of Tom's power secrets, and we plan to investigate more on that later.