JohnSThanks! ...ButWhatAbout?...

[alice@domain.elided]

JohnS,
Thanks for your GM engine history lesson ...but you leave me with a 
question.
I have a buddy ...nuts about GM.  For years, he advised me to swap 
out the IH 345 for a GM 350.  I forget all his reasons, but they 
mostly include parts availability, lower rebuild cost, etc... we 
never got around to really comparing their relative construction, 
power, etc... I think he cited lighter 350 weight as an advantage.  
I am a beginner at this stuff, so tell me (and others) all the 
reasons to stick with our IH iron lumps?  Are they more durable? (But 
as you say, GM makes a truck engine).  Is the IH engine more suitable 
for low end grunt? (You may have actually said this already --hey I'm 
a novice at this)  I tend to like keeping things original and believe 
the IH engine to be "tougher" (just don't ask me to define that).

All comments welcome!  Mark