Stroker Kit Schooling

Allpontiac.com
Frank Gostyla of AllPontiac.com, in Richmond, Virginia, says that he takes Pontiac performance very seriously, and is sincerely enthused with the number of maximum-performance Pontiac parts from all manufacturers presently on the market. "It's a good sign for the hobby, and we're hearing that our large-bore IA II block and high-flowing Tiger heads are helping Pontiac hobbyists compete with similar-sized engines of other makes on the track. We're hoping that our new rotating assemblies will provide racers with a performance edge."Gostyla says that generally speaking, adding stroke is an easy way to increase available torque in any application. "It seems our customers are interested in producing as much power as possible. The only negative effects we've seen from additional torque is in applications where tire size is limited or the chassis cannot simply handle the power. In these instances, additional torque can induce tire spin, ultimately slowing the car down.

"Testing of our 505 and 535ci engines, which contain the same bore diameter but different stroke length, indicates that with the same heads and camshaft the two engines produce nearly identical horsepower numbers, but the 535ci clearly produces more torque-about 40 lb-ft. If the added torque can be applied, the owner can usually install a lower (numerically) gear set and run quicker, even though trap speed stays about the same."

Gostyla tells HPP that he partnered with SCAT and combines its forged-steel crankshaft with his company's large-bore IA II block. "SCAT's crank contains a 3-inch main journal diameter and is available with a stroke length of 4, 4.25, and 4.5 inches. That allows us to produce engines that range between 477 and 541ci using our IA II block, which seems necessary to seriously compete with the large-displacement Chevy engines commonly seen on the track today."

In addition to a SCAT crankshaft, AllPontiac.com's complete balanced rotating assembly kits include SCAT 6.8-inch forged-steel connecting rods, forged pistons from JE Pistons, and a host of other high-quality components with pricing that starts at $2,695. "We also offer a complete short-block, which includes a rotating assembly installed into our IA II block. It's completely machined and assembled, and is available in a number of displacements, ranging from 477 to 541, for just $6,595."

When asked which combinations sell best, Gostyla replies, "The trend we're seeing right now is towards the 535ci combination. It seems most popular because it includes an IA II block with a 4.35-inch bore and a 4.5-inch crankshaft. That bore diameter gives owners at least one future rebuild, which might then include taking the block to our maximum-recommended bore diameter of 4.375 inches, subsequently producing a 541ci mill."

Conclusion
You may have noticed that Kauffman Racing Equipment (KRE) wasn't included in this story. The reason is we have a full buildup of a KRE 505 stroker engine following this story, so Jeff and Mark Kauffman's comments regarding stroker combos will be published in that article.

Though there may be other companies presently producing Pontiac crankshafts, and a number of skilled builders using various rotating assembly kits, it wasn't practical to contact them all. So we limited our story to those products that seemed most popular, and sought the opinions of a few Pontiac-specific builders who were quite familiar with each. That doesn't mean, however, that the components from other companies-or abilities of other builders-are inferior to those we've featured.

After hearing the comments from our panel of experts, we learned that the quickest and most affordable way of increasing the output of virtually any combination is with a stroker crankshaft, and that the resultant torque increase can be beneficial in dedicated street and race applications alike.

Such kits might make hobbyists look at that once-mundane 350 or 400ci block in a different light, or provide an edge against that large-cube big-block Chevy in the opposing lane. No matter the case, with so few negatives associated with them, stroker kits seem like a positive step towards maximizing your Pontiac in a number of ways.