stroker motor problem

[mudslinger]

I have a bit of an issue! I have just completed my first 4.6 stroker build with 90 renix block, and was in the process of trying to break motor in when I began to hear a bit of a bottom end knock at idle, Seems to decrease a bit upon acceleration. And the power isnt as anticipated. I am probably guessing that it is a rod bearing or piston. If anyone has any helpful hints or tips that can help to determine what the issue might be. I would highly appreciate it. I can give more info if needed to help with the process of elimination.

[dwg86]

What is your oil pressure?

[Cheromaniac]

I began to hear a bit of a bottom end knock at idle, Seems to decrease a bit upon acceleration.

It's more likely to be a main bearing. A worn rod bearing usually causes a louder knock when you load the engine. Either way it looks like you're gonna have to pull the oil pan and check all of the rod/main bearings.

[SilverXJ]

Before you do anything check the flex plate to torque converter bolts.

[mudslinger]

My oil pressure shot up to 25 psi when it first started then then began to drop to no pressure. I installed new main and rod bearings and torqued everything down to spec. I am a bit confused on how this can happen. Do you think I installed a bad bearing somewhere? Would there be plenty of scarring to indicate what bearing or bearings are crap? Guessing that the motor has only 30 miles

[Cheromaniac]

You could just have simply installed the wrong undersize bearings and have too much clearance.

[SilverXJ]

Did you plastigauge the bearings to see the clearance?

[mudslinger]

No unfortunately I did not plastigauge before install. I guess I just trusted machine shop to have ordered the right bearings.I just pulled rod bearings out today and it looks like there is definate scarring so I will proceed to pulling crank