Always funny to read these type of posts...
Ok, the truth is the 4.6L engine is notorious for having a very strong bottom end with 4-bolt main caps and a deep skirt. WINDSOR built 4.6L engine have
4-bolt main caps with dowel pins as well. Stout stuff for any engine.
The top side of the engine is bolted together using steel laminated head gaskets. The weak part is the piston design and powder metal connecting rods. I don't care what anybody tells you they have done with their car. I don't care what you have read in magazines.
The hypereutectic pistons have given out on NATURALLY ASPIRATED 4.6L engines. Cracked ring lands, broken rings lands, and/or holes in the oil feed holes are very common. The connecting rods are usually spun well past their engineered tolerances and with boost pressure present they have been known to shear the bolts out of the caps and send the rods through the block. Or they just snap at the mid point and create a nice mess.
To supercharge any 1991-2004 4.6L 2V SOHC engine is a gamble. High or low mileage...does not matter.
I had 20k on my 4.6L when the 4.6L piston gave out and broke a ring land. There was only a small warning sign that I had before it let go. Excessive blow bye was seeping through the intake manifold. It just laid over and stopped pulling on the high end. The car was tuned by Jerry W. so I don't think you can argue it was a bad tune.
If you have the very best dyno tune...things can still go wrong. Bad gas could easily cause the engine to knock. Imagine a fuel pump going out or something as simple as a bad tune letting more spark timing advance when it should be pulling it back.
Even the best scenarios cannot be controlled. This is why Ford used forged pistons, forged connecting rods and a forged steel crank for the 2003-2004 Cobra. They didn't want you coming back looking like a 2V engine.
So the bottom line here is...but a blower on the 4.6L and you are on borrowed time. How long? Depends...really it does.
My new 2000 4.6L engine has lasted 6 years with 10-psi of boost. It is a completely stock GT engine. Will it last forever? No.
The Ghost,
Every couple of months somebody asks the same question you do. Clearly you have not done any homework on your own. Frugal, perhaps, but most likely just cheap. The M90 that ALLEN uses on the REV-I kit is actually a GEN-III M90 with an "S"-port. Hence the name M90S.
Any blower you pick up from a used SC or XR-7 is going to be at the best just a plain GEN-III M90. Most of them will be GEN-II's. The snout is a different length on the ALLEN kit and also machined to accept the clamp for the ALLEN kit. Also, you are getting a brand new M90S, not a used salvage yard unit that you might have to rebuild.
The new ALLEN kits (REV-II only) use the GEN-V Eaton M90 which is the best of the best. What you should be doing is figuring out how to fit the GEN-V M90 to the REV-I kit. That would be something you would be commended for.
Hmmm...try something new...something different.
A-Train
