[G. Craig]

Originally Posted by Go Goody

The problems have started when you try to put more than 6 lbs of boost into the engine.

The compression ratio on the SRT 6.1 HEMI is 10.3:1 which is fine for naturally aspirated engines. In a nut shell high compression ratio when mixed with high boost levels can results in detonation and ultimately broken pistons. I predict there is going to be a lot of cracked and broken pistons and/or blown head gaskets as enthusiasts try to push the boost levels higher and higher. If a supercharger or turbo set-up is part of the game plan than owners should rebuild the engines with lower compression, forged aluminum pistons @ 9.1:1 or less, designed for use in boosted applications along with replacing the powered metal rods with good quality forged steel rods.
The SRT 6.1 HEMI appears to be well thought out and engineered for high performance duty.
o The basic, deep-skirted engine block structure was redesigned with reinforced bulkheads to handle higher loads.
o Cylinders are honed with torque plates to ensure a truer bore, to reduce friction and increase power.
o Oil squirters, aimed at the underside of each piston, are added to aid piston cooling for engine durability. (I am especially impressed with this feature, it could allow for a higher AFR during boost without fear of burning pistons.)
o The SRT 6.1-liter HEMI’s crankshaft is forged from micro-alloy steel and rotates in tri-metal main bearings for high-load capability. The crankshaft damper is retuned for higher engine speeds.
o A billet steel, high-strength camshaft features more overlap and lift for better performance.
o The hollow exhaust valve stems are filled with sodium to dissipate heat efficiently.

The Mopar enthusiasts have plenty to be excited about, SRT is engineering some good stuff and Dodge is building it.