jtettenb

I am rebuilding a 289 with unknown mileage. Is there any way to tell if the pistons I have are still good? also someone told me that if I get new pistons I should make sure I get them before I get the machine work done. why would this be? thanks alot

67mustang302

Whether the pistons are still good is gonna depends on what you want to do. If you want reliable performance, and you have some heavy cast piston, then I wouldn't consider it good. And the reason for having the pistons is so they can machine the cylinders to match the pistons and have the proper clearances

If you do reuse the pistons you have, basically you don't want any deformities, cracks etc. Make sure you clean the rings lands out though if you want the rings to seal

jtettenb

If I dont go with the cast pistons what type would you recommend and why? this is my first rebuild and I dont know a whole lot about piston types. thanks for your help

67mustang302

There's 2 types of cast, standard and hypereutectic, then you have forged. Forged would be the best for performance because they're the lightest and strongest, you can use nitrous or super/turbo chargers safely(provided everything else is set up right). Hypereutectic is cast, but has a high silica content, so they're "stronger" than a standard cast piston, but more brittle, and generally NOT recommended for nitrous or forced induction(supercharing etc), and they tend to fracture when subjected to detonation(they're decent as long as you don't detonate). And standard cast, which are the weakest. Forged are the most expensive, cast are the cheapest, hypereutectics are sorta middle of the road. If you plan on going forced induction, using nitrous, or tunring rpm while making good poweron a regular basis then you're prolly gonna want forged for the added level of insurance. Cast or hypereutectic will work too, but it limits you as far as total performance, so it comes down to what you want to do with the engine. Regardless of what type you use, get quality stuff, you buy cheap, you get cheap. And with pistons, you want them to be lighter and stronger, which is why a lot of guys go with forged pieces