What is your cut off for rpm? are you running it to 6k? More? just wondering if it gets valve float up high. I am building my engine similar to yours with a little bigger hyd. cam and wonder if I am making a mistake. Probably should have used your cam. My cam is spect. at a couple hundred rpm higher than yours.
There is absolutely
no way to determine what any particular Hydraulic Roller Camshaft will rpm to in an RB Mopar Engine, mainly because these Blocks were
never BUILT or intended to run a Hydraulic Roller Lifter.... the Lifter Bores are far too short.... and the Oil gallery far too LARGE where it intersects the Lifter Bore.... with far too SHORT a wear area in the Lifter Bore below that Oil gallery.
In a nutshell what I'm saying is this....
on a Block with very little Lifter Bore "wear"..... a particular Hydraulic Roller Cam may be capable of maintaining good power right to 6,000 rpm ?
then,
Same Cam installed in a Block with worn Lifter Bores.... may be all done making power at 5,200 rpm ! and no amount of tuning will increase the Lifter Pump up that can be maintained in the "Hydraulic" Lifter in the worn Bore !
That's what happens when you are trying to "balance" a Roller Cams more aggressive Lobes.... faster/harder opening & closing.... against... the ever also increasing V/Spring pressures required to keep things in contact with the more aggressive events......
with a "Hydraulic" plunger as the weak link ?There is a point where the Oil
pressure takes the path of LEAST RESISTANCE ..... and if that is OUT "around" the Lifter Body in the WORN Lifter Bore as opposed to
INTO the Lifter to keep it pumped up ? = FAIL to maintain the intended Lobe profile or rpm.
