Hey guys just a real quick question. My motor spun a rod bearing and so now I need to do a quick fix to get it back on the road. I am just weighing my options right now. I am going to keep the 2.8 block until I get more information on the '99 3400 motor. I am looking at going to a 3.1 crank since I know I have to buy a new crank and some rods anyways.

My question is this, can I still use the 2.8 pistons or do I have to switch to 3.1 pistons. I would like to keep using my pistons because mine are flat topped, I believe I have read that stock are dished.

Also what's a good cam that will show modest power increases that doesn't cost a whole lot.
Thanks guys

The stock 2.8 pistons are flat top pistons and you can't use them with a 3.1 crank. You have to get different pistons. The piston everyone uses on this forum seems to be the Silvolite 1486 pistons for 3.1L iron head. They quote 8.8:1 compression for them but no one really knows what the actual ratio is with the fiero heads. If the 3.1 iron heads have the same size combustion chambers as a fiero than it should be 8.8 to 1. You will also need an adjustable fuel pressure regulator to increase your fuel pressure.

Do a search for the 3.1 engine here on the forum. There is a ton of threads on this subject.

We calc'd the 1486 as 8.95:1 with stock gaskets.