Re: It's Just......Wrong!
Reply #48 –
OH BUT It IS, YOU SEE THE 4.6L WAS DESIGNED TO DO 3 THINGS
Make decent NA power
Get great gas mileage
Last for many miles.
Not to mention the most important issue be cheap to produce.
In order for the engine to rev freely and get great mileage, the internals were made with lightweight (py) components. It has "I" beam connecting rods that are about as thick as my thumb, hyperautectic pistons, and ringlands that break extremely easily. Hell, I've seen 4.6's break ring lands just from spark knock! The stock shortblock was not meant to have any type of forced induction PERIOD. The parts just can't take that stress. If you force induce one and it doesn't break immediately, you are only running on borrowed time. The only real "safe" way to force induce one is the never go over 6psi, run it rich and pull the timing out. Most V8's even force induced ones would still run like , but since the 4.6 does well with forced induction, you could still turn decent numbers with this setup. That doesn't safe-gaurd it from blowing up still. Most people try and get away with it anyway simply due to the fact that a forged motor is that pricey. It is actually cheaper to just replace the motor when it breaks (as another DOHC can be had close to new for about 1,500.00) . Don't belive me? go to the corral or any mustang site for that matter and do a search with "blew my motor up".