most likely the head.. runs good no sound but when I bring up the rpms it starts to make a bad knocking sound what should I replace

 

Heads don't "knock" they can "tick" from valve train noise.

Knocks are usually bearings, most often connecting rod bearings.

Connecting rod connects the piston with the crankshaft.

When the bearing gets loose there is a "gap" between the connecting rod and the crankshaft.
When the cylinder with the bad bearing Fires, the piston is pushed down with alot of force.
This closes the "gap" quickly and makes a "knock" noise, and it gets worse over time as the gap gets larger.

If you want to test if this may be the problem, then you will need to stop one cylinder at a time from firing and then see if knock noise gets quieter.
First start engine and listen for the knock, now shut off engine
Pull both spark plug wires for #1 off on each coil
Start engine, yes it will be missing, but listen for knock, if it sounds the same then #1 isn't it

reconnect #1 wires and now do #2
ECT, repeat for all 4 cylinders

 

I have already broke a connecting rod and put in a new one with piston and rings then did the front two rod bearings but I will test tomorrow

 

Did you pull off the caps on the crank bearings to inspect for wear?

And thats only 3 rod bearings replaced???
I assume all 4 are new

 

i didnt even look at the back two just checked for play the rods and caps looked ok... shouldve changed them to bought the set and didnt change them.. But i changed the very front because it and the one that broke was black... it had a cloged oil pump screen... I tested it and it sounds like its the front again.. Do you need loctite on them could they have came loose? Thanks for the help..

 

Connecting rod caps only have 36ft/lb torque, but not likely to come loose unless something else is wrong.

You can't(shouldn't) reuse connecting rod bolts and nuts from a connecting rod with a bad bearing, or broken connecting rod, they have often been stressed and could break.

Bearings are soft metal, oil is not used strictly for lubrication, its the cooling system for the bearings, if flow decreases bearings heat up and get too soft, that's what causes a bad bearing, the heat from less cooling.
And rod bearings especially because they absorb the explosive downward pressure when a cylinder fires, if rod bearing is hot and soft it flattens a bit because of the force..........
And you start to get the knocking noise because there is now a gap.

Crank bearings can be effected by low oil flow as well but they need to get very hot, at that temp the soft bearing metal starts to fuse with crank journal metal, like welding, then the bearing "spins" inside the cap, this blocks the oil holes so bearing gets even hotter, engine can grind to a halt at this point but one thing is for sure, once it is shut off and cools down the crank will be frozen, welded in place by the spun crank bearing.

Bearings like these do not spin, like some other bearings, these bearings are in a fixed position held in place by the connecting rod and cap, or the engine block and cap, this keeps the oil holes lined up all the time, the crank is the part that spins, and that area, between bearing and crank journal, is the part that heats up from friction.

Thats just FYI stuff.

Bearings can be looked at and cap reinstalled, they are not like a gasket that shouldn't be reused, a good bearing will last as long as a new bearing.
You just need to look at the bearing 1/2 that is in/on the cap, it will tell the story for the whole bearing.

Google: worn engine bearing images

Have a look at the differences, it will help you ID any issues

 

when I got it back together it was fine for about a day of driving then starts having problems again.. but when the rod went I had to clean up the crankshaft.. Guess its time to pull it again.. Thanks,

 

that is bad news right there

the knock problem is worse than you think , that engine has been starved for oil lubrication

time for a complete rebuild it is