The valve reliefs were cut with precision. The intake pockets are 0.270″ and exhaust pockets are 0.064″. Notice that the pin bore location encroaches into the oil ring groove. Diamond supplied a set of support rails that are installed prior to the oil ring package. These provide footprint support for the oil ring package. Scott [...]
HONING THE CYLINDERS Following a recommendation from our buddies at Sunnen, we visited Gressman at Gressman Powersports in Fremont, Ohio (Gressman has built a number of 632 motors, in addition to countless big-number drag, sprint car and road-race engines). Naturally, the Ohio winter weather forced us to drive in sub-zero temperatures. Even with the block [...]
PROJECT 632, PART 2 We hone the block and determine bottom-end clearances. by Mike Mavrigian photos by author With our new pistons in hand, it was now time to hone the cylinders to size. As you may recall from our previous article, our target is to build an all-motor 632 cubic-inch big block featuring 15:1 [...]
Dart 11-Degree Big Chief Cylinder Head Specs P/N………………………18500000 Material…………………355T6 aluminum alloy Comb. Chambers……….56cc (70cc also available) Intake valve dia…………2.470″ Intake port dim. …………1.815″ x 2.725″ w/3/4″ radius Intake port volume………FP CNC – 497cc Intake port location……..Raised 1.500″ spread ports Exhaust valve dia………1.800″ Exhaust port volume……185cc Exhaust port dim………..2.020″w x 1.780″h Exhaust port location……angled & raised [...]
DART RACE SERIES BLOCK Dart’s new monster big block offers a choice between 10.600″ or 11.100″ deck heights, a cam tunnel that’s moved up 0.600″ for better connecting rod clearance with stroker cranks and a choice between 4.840″ or 4.900″ bore spacing. The new tall-deck block offers engine builders great versatility with variable lifter locations [...]
We build a big, big block drag mill just for the sheer hell of it. by Mike Mavrigian photos by author Some folks love to claim that bigger is not always better. While that may be true in some cases, let’s face it…when the conversation turns to displacement, well, bigger cain’t never hurt. After all, [...]
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