when someone tells you that you need forged internals what all parts is he/she talking about? Are forged internals more durable than regular or just lighter at the same durbility. how much can factory internals take compared too?

 

"Internals" would be the internal parts of the engine, mainly, crankshaft, connecting rods, and pistons. Forged internals are much more durable than the factory junk... Your factory rods (on the 4.6 engine) are rated to 450 HP, after that they're likely to break... the crank and pistons are not rated to much higher. If you want more than 400 RWHP you're going to have to either rebuild the engine or get a forged short block. Forged goodies should be good for up to 700-800 RWHP. The next step up is billet (expensive!).

Edit: Since you have a 5.0, I'm not sure on the ratings... but you have forged pistons, but regular rods and crank... The weakest link for you is your block. A 5.0 expert should probably be around with numbers for the 5.0 engines break points.

 

what he said ^^ Forged meaning new rods, pistons, and crank - also need new rings, bearings, etc.

 

u would be likely to need forged internals over a fox body. fox bodies (87-92) already have forged pistons since in 93-95 hypertectic pistons. hypertectic are just a cheaper piston compared to a forged and jsut are as durable if u plan on using boost or spray

 

Ok, there are typically 3 types of processes for forming metal shapes... Forging, Casting, and PowderMetal/Sintering.

Casting is when you pour molten metal into a mold and when it cools, Viola! you have a shape.

Forging is a bit different. Forging is when you take a slug of metal (generally a cast ingot) and you form it using pressure. Ever here the term cold rolled steel? Cold rolled steel is when they take a slug of steel and roll it, unheated, into a shape. Hotrolled steel is when they heat it up while rolling it. These processes yield different metalurigical properties. To make a piston, they take a slug and stick it in a die, then apply a burst of pressure to form it. The advantage to forging is that you essentially work harden the metal and sort of "compress" the molecules into shape. This gives you a very strong piece of metal.

Powder Metalurgy is an awesome process. Its when they take actual powdered metal, and they compress it into a shape, then heat treat it just below the powders melting point(sintering). The advantage to this, is that you can "alloy" metals that normally couldnt be. If you have two items, one forged and one made with powder metalurgy, the Forging will be slightly stronger. Because you can alloy unusual metals together, you can make something that is very well suited to a particular application. Also, there isnt as much waste with PM and you dont need as much machining. Most good wrenches are forged, but many sockets now are made with PM.

Hypereutectic pistons are cast pistons, but they use a higher percentage of silicon in them. The process of making them is slightly different than casting which allows for the extra silicon to be added. The side effect of these pistons is that because of the extra silicon, they are stronger, but more brittle than regular cast pistons. A forged piston uses less silicon then hypereutectic pistons but are stronger and less brittle, once again, because of the forging process.

Many connecting rods are made using the PM process. It allows for them to be fairly balanced right from the factory and only require minimal machining.

Jim

 

How much is it to forge you internals?