<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lynn</div><div class="ubbcode-body">Didn't one of the car mags have one that had a transplanted 421 SD?
Forgive my Pontiac ignorance, but are the 389 and 421 pretty much the same externally? </div></div>
Maybe? This one had a 421 HO installed in engineering and Bobcatted at Royal for the Car and Driver test.
Yes, 389 and 421 are dimensionally the same (likewise other Pontiac V-8's - no "big blocks"
.