flatbird

iTrader: (11)

So I completely rebuilt the entire bottom end. New custom grind cam, trick flow push rods, 1.6 CC NSA RR and single piece racing valves. I have a knock, once it's warmed up, ps it's running w/ open exaust right now. Also, I have an exhaust leak. It definately sounds like a rod knock but it has less than 100 miles on it. Any ideas? It's my LT1, all other mods are below.

RamAir95TA

iTrader: (2)

Did you build it or did a machine shop do it?
What are your other mods (none listed "below")?
Post a video of the noise.

We didn't build the motor so unfortunately we'll only be able to tell you what the noise is, not what is causing it.

96capricemgr

iTrader: (1)

If it sounds like a rod knock start looking for glitter in the oil and filter before risking running it anymore.

Tell us more about the engine. I don't like the sound of

flatbird

iTrader: (11)

A reputable shop hot tanked the block, honed the cylinders, cam bearings, Rebuilt and decked the heads with the racing valves and installed new freeze plugs in the block. What about replacing valves that are two pieces forged together wiith single piece stainless steal valves worrys you. To be honest with you the knock is so faint that you would even be able to hear it in a video. I've already tried. It runs like a bat outta hell. I'll change the oil and get back with you. But why would the knock be nonexistent when cold and noticeable when warm?

96capricemgr

iTrader: (1)

The ONLY instance I know of a stock valve failing was a nitrous system problem. If the shop sold you on "single piece racing valves" particularly without port work to compliment either they knowingly took advantage of you or are clueless themselves, neither is a good indicator for your build.

a HUGE number of "rebuilt" LT1s are a step backwards and the owners never realize it because they never have anything good to compare too. At the track I have spanked big block Vette, a couple nitrous LS cars, stroker LT1s in f-bodies. They all thought they had something great till a stock shortblock NA Caprice embarrasses them.

If you are not worried about the engine holding together take it to the track and measure the performance, the butt dyno is useless, unless it has EXPERIENCE.

flatbird

iTrader: (11)

I'll go ahead and stick with my lightweight valves that flow better and provide me with piece of mind. It was worth and extra $100 IMO. And a 100 shot is definitely in my future.

96capricemgr

iTrader: (1)

Do you have documentation they they are lighter and flow better? $100 isn't enough to buy quality parts.

Far as stainless I have found stock exhaust valves to be non-magnetic FWIW.....

LigHtEmUp01

bearings may be wrong size or you could have a bent rod. did the rotating assembly move freely before you put the pan on and called it a day?

96TransAmboosted

iTrader: (8)

What's your oil pressure. Im sure if you are having bearing issues your oil pressure is now lower than before.

raroz28

iTrader: (1)

What did you have done to the rods and what bolts did you have installed into them?

What was the bearing clearance when you assembled it?