My newly build engine (dyno time only) has been set up with ST heavy double springs and SUB lifters.

At idle, it is substantially noisier than my stock NB. Valve train noise settles once off idle.

It was set up with factory clearances (which I have not checked myself).

Is increased noise to be expected with the heavy double springs?

 

It took me a ridiculous amount of time to set lash in-spec when I installed OS valves and SUBs. Improper lash can be really noisy.

 

Agreed. Checking and changing lash can be done reasonably efficiently, especially if you are lucky enough to have the Mazda SST, but once you venture into SUB land, that goes out the window as any change requires removal of the cams, and then refitting, retorquing the cam caps each time to get the correct measurement. Very painful.

 

My top end was only slightly noisier with tomei poncams, Maruha subs and the heavy doubles. I can take a video when it's back together, just started putting it back together after doing a rear main seal job.

 

I have the exact same setup. It is noisier than stock. Took a while to get used to it.