Got to thinking about it...

my valve train seems a bit noisy. and considering it's stock lifters, aftermarket pushrods and springs and stock rockers, I wouldn't expect any more noise then stock really.

Also, when I swapped out the Yank converter for the Vigilante a few weeks ago, we turned the motor over by hand a few times to get to all the bolts. When all was said and done, we fired it up and there was a lifter or two tapping. Apparently it had bled down. But the thing was, it took nearly 3 minutes to pump back up. What would cause this?

Is there a possibility I have some bad lifters? Also, how do I go about doing a pushrod length check to see if I need longer or shorter pushrods?

 

the LS1 in general is a bit more vocal than your average hydraulic roller motor...

i don't think i've ever heard an LS1 that didn't make one or another valvetrain noise from time to time.

unless you hear something glaringly obvious or extremely abnormal, i woudln't worry too much.

 

when i swapped my valve springs a few weeks ago, the lifters bleed down apparently, and it took a good 2-3 min for them to quiet down again.

it suprised me

but then again, i think i have a few bad lifters as well...so who knows if my experience was any different than yours

 

Yeah most people report alot more valvetrain noise after a cam and/or header install. I wouldn't worry about it.

 

The valve train is a little more noticeable on the LS1 because aluminum doesn't dampen the noises like cast iron.
I really can't say on the stock lifters with heavier valve springs because I went with Comp "r"s which are really touchy about preload so they don't play well with non-adjustable rockers.