500hp Ford Power Stroke Buildup Part 1
Last May, we kicked off our “Serious 7.3L Upgrades” series on our ’97 F-350 with a hybrid injector upgrade (which culminated in 436 rwhp, Aug. ’11). Now, exactly one year later, we’re at it again with our 7.3L Power Stroke. And this time, we’re gunning for 500 hp at the wheels. For all intents and purposes, this new series of installments is much more serious than what we brought you last year, but we’re willing to reinvent ourselves and have intentionally called this new four-part series what it is: a quest for 500 hp. Along the way, we’ll be upgrading our valvetrain, installing a completely new turbocharger system, finagling a massive intercooler into place, amping up fuel delivery, and implementing more aggressive tuning.
| Starting at the top left corner and moving clockwise, Summit Racing supplied us with a Comp Cams valvespring shim kit (0.015 inch, 0.030 inch, and 0.060 inch) and a set of Comp Cams valvesprings, while Hamilton Cams’ chromoly pushrods were used to replace the stockers. Luckily for us, we were able to borrow a valvespring compressor tool (bottom left) from fellow 7.3L owner Chris Vanderford.
We’ll begin our build this month by eliminating a known weak link in the 7.3L’s valvetrain: flimsy springs and bend-friendly pushrods. Although it was a very tedious task, Flynn’s Shop installed our aftermarket valvesprings with the heads still on the block. This was accomplished by performing the work one cylinder at a time and required a helper to manually roll the engine over to put each cylinder at top dead center. We think upgrading the valvetrain is $400 well spent to ensure our 7.3L can handle the extra abuse we’ll be subjecting it to. Going forward, the engine will be seeing more rpm and higher boost pressures, so ruling out this problem area beforehand was key.
