340 Noise

[Moparty]

I just put a Purple hydraulic cam with new rocker heads and push rods in my 340 Duster. But I'm hearing a little noise and losing oil pressure as the engine heats. Could this be the enging bearing? If I have to tear down the engine, I'm thinking of boring the block & putting forged pistons. Will this be worthwhile?

 

[1968FormulaS340]

Need more info....

Its normal for oil pressure to go down as the engine heats up...

What is your oil pressure?

What kind of noise?

What kind of oil did you use when you broke in the cam? (its easy to kill a new cam with the crap oil out there)


Just switching from cast to forged pistons will give you little to nothing.....


Why do you think you need forged pistons?

 

[Moparty]

about 25psi. it is as slight rattle or vibrating noise deep in the engine. slight but not normal. i used heavy duty truck oil for the break in. i thought forged pistons dispersed heat better and had more strength at high performance levels. the rings will be thinner too for less abrasion?

 

[Moparty]

Losing more than 25 psi. A slight rattle---slight but noticible.
I used heavy duty truck oil for break in.
Aren't forged stronger and disperse heat better?
I also put in roller rocker heads.

Thanks

 

[340sFastback]

You might want to pull the intake and check for a worn cam lobe. That happens sometimes with flat tappet cams they don't break in correctly and wipe a cam lobe out.

 

[340sFastback]

I also put in roller rocker heads.

I never hear of "roller rocker heads" before? Do you mean roller rocker arms?