I'm thinking the sustained 5000-6000 RPM that street cars don't see is part of the problem.

I see.

in the article posted by Matt T. is states the Ilmors are at 10.3:1 compression already so to take any type of additional boost over just a very nominal amount they would need to have compression lowered on them which varies in the difficulty to accomplish....shorter crank stroke, shorter rods, different pistons or different heads, thicker head gaskets or a decompression plate....all of those come with varying cost or issues

plates and gaskets increase the likelihood of failures especially at higher compression ratios which is playing with danger for adding a super charger, head work for compression is a skilled procedure, crank, rods, and pistons means tearing into the bottom end and if you go that route you are basically rebuilding your engine and you might as well "go for it" and then you will be supercharging a former Ilmor engine

texas, you worded it much better than i did in my original post. "I would like to supercharge a former ilmor engine"
when mine were apart i found a great engine but one that seemed to be designed to handle just over 700hp and thats it. I already upgraded my rods and would still have to do pistons and valve train. So i feel I could easily add just about 4 or 5 lbs of boost to wake the motors up a bit. i think my boat would be perfect at about 800hp per side.

SC'ing the Ilmor V10 in a stock form would be unwise. Cars don't run steady state at the higher cylinder pressure levels and constant stress so they get away with far more. The stock engine internal components have trouble living under heavy stress with extra pressure. If one were to build there motor with forged rods, forged pistons then it would be possible if somebody built a kit but that's tough with the closed cooling, etc. The compression is really not a worry with 5-6psi of intercooled boost and 91 octane, slightly reduced spark curve.

SC'ing the LS based engines is a different story though.....

Maybe it has something to do with the stability of the Ali block under boost /high cilinder pressures making the crank flexing the cilinder block ?

Ding Ding Ding! We have a winner! Not sure if this was addressed in the new GEN of motors but that was a huge concern on the previous design and dont believe it was addressed in the latest offering from Dodge. Not really a flaw in the design just the block was designed for a certain HP range while keeping the weight down. That said if you were to keep the boost/hp/cylinder pressure numbers on the lower side I would think you could get could possibly get away with it. It would be a cool piece with a whipple for sure.

Chris dont do it they run great

We have played around quite a bit..........
Good post Dustin and Neil.

Cant leave well enough alone, can we!?!?