There are plenty of cars running 9 and 10 second ETs using cast cranks. Forged cranks for Pontiacs are rare and expensive, they were made many years ago in the 4" stroke by Pontiac for the 421 SD engines. There were even a few 4.21" stroke forged 3" main cranks made if I'm not mistaken, again super-rare and expensive.
The 4.25" stroke cranks are made for 6.8" long BB Chevy aftermarket rods using the 2.2" rod journal. The Pontiac 455 4.21" stroke 2.25" journal crank can be offset-ground to the smaller BB Chevy size to get the added stroke. Not a lot of difference in stroke length between the two, .040" more stroke doesn't make a big difference in how the engine feels.
The nice feature about the cranks Ken is selling is the fact that you can use Pontiac rods and drop it into a 400 block, no expensive BB Chevy rods and custom-pistons needed. ALL Pontiac rods are the same length at 6.625" (not counting the common 265/301 economy engines and super-rare 366 and 303 race engines).
Let's go racing!
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