Edelbrock RPM/Mopar 452 cyl. head and Roller Rocker install. Q's....

[mopar_440_Challenger]

Hey all

     Last weekend I started tearing down the top end of my Challenger to install an MP .557 solid cam, Mancini Aluminum Water pump, Edelbrock RPM/Mopar 452 (straight plug) heads, and Hughes 1.5 roller rockers...
     Upon setting up to determine pushrod length, I noticed that at 0.00 lift, the rocker and spring retainer barely have .002" clearance...so I was looking into getting some rocker shaft pedestal shims to help raise the shaft...also, at max valve lift, my Crane 3/8" pushrods that I have for solid cams w/ adj. rockers look dangerously close to rubbing the wall of the pushrod tunnel...is it common to have to get the pushrod holes on these heads enlarged to accomodate a 3/8" pushrod?? My Comp Cams tool is of the 5/16" type and it seems to have a bit more clearance...I am just scratching my head trying to figure out where to go next...and as for "side clearance" between the rockers, does anyone one if they're referring to the pair of rockers that are closest to eachother just in between them, or if it's necessaryto attain the same clearance on both sides??
     The car is as follows - '70 Challnger w/ 440 & 4 spd., 3.91 gears, M-1 Intake, full MSD ignition...I have been debating mailing the heads off to get the pushrod holes opened up since no shop here seems to be Mopar friendly...Has anyone run these heads ootb while still being able to clear a 3/8" pushrod?? Oh, and the springs that come on these heads...I have read the max valve lift they'll support, but my question is if anyone knows, will they work well with that MP .557 solid cam?? Any help / advice is greatly appreciated! Thanks soooo much for the help ! Take care!!

[nivvy]

http://www.cuda-challenger.com/cc/index.php?topic=46346.0


 

 

[Chryco Psycho]

With every set of Iron heads I port I always port the walls by the pushrods to get adequate clearance for the 3/8" pushrods , you need to do this , I use a carbide burr & a die grinder to remove the metal . the side clearance need to be the total for the pair not beween & on the outside of each rocker . From the info provided I have no idea what springs are on your heads

[mopar_440_Challenger]

Thanks Stroker and CP, I def. appreciate the info....oh, CP, as for the springs they are the springs that come with the heads from MP/Edelbrock as they carry that "good to .600" lift" but the paper that came with the .557 cam didn't give any type of spring requirments

[nivvy]

my eddy rpms were fully worked and had the push rod holes opened up..... ti retainers roller springs the works... what i dont like he most about box stock heads like that is the 7* locks....