Yes, many run fine with cracked heads, some don’t. With a magnum you still have a shortblock based off the poly 318 with 2 bolt mains and heads that flow nowhere near a late model Hemi. The basic 5.7 Hemi comes with cross bolted mains, great flowing heads, better factory machining, better gaskets/seals and puts out more power than any factory LA or magnum. Not to mention factory 6.1 Hemi blocks can support 800 HP with the addition of main studs.
Don’t get me wrong, I enjoy driving and working on my 340 but it takes a fairly radical LA or magnum to match what the late model offers from the factory.
What’s really nice is we now have a fairly affordable and plentiful option for a power plant for our cars.
