I gather the ITR valvetrain has different lost motion assemblies right? Just what is a lost motion assembly? I am running spec b with toda valvesprings, toda timing belt, stock retainers, and spoon cam gears. My valvetrain is hella loud when the engine is cold. It sounds like pebbles in a tin can. I have been running spec bs for about 20k miles. How many miles have you guys put on you gsr head with spec bs? Should I switch to ITR rocker arms and lost motion assemblies? (whatever those are)

 

You are running Toda spec B's on ITR valvetrain?

Ok... you need an upgrade. Possible that the valvetrain you are using is damaging the cams. Toda recommends the Toda valvesprings with use of their cams. Otherwise you might damage them.

Not to mention the Spec B's are not supposed to be ran with a weak valvetrain like the GSR/ITR. You need something more beefier.

 

read again dude, I said I'm running toda valvesprings. I know the only valvesprings to use with toda cams are toda valvesprings. I am worried just how compatible everything else in the cylinder head is with these cams.

 

oh ok ok, my bad man.

I think the GSR LMAs are just fine. I know lots of guys running the Skunk2 stage2s which have more lift on the cam than the Spec B's, and they take their car to 9500 consitantly. No problems yet.

 

umm... have you considered upgrading your retainers? And when is the last time you did a valve adjustment? Give that a try and maybe it will become quieter.