mrr23

iTrader: (3)

all in a nicely packed box


one cylinder set up


rocker has a polymatrix bearing. no needle bearings means less friction loss.


Rocker stud towers had to be cut down .170" to fit the shaft mount. the holes had to be drilled and tapped to 3/8-16 thread pitch.


You can see where the valve cover wall had to be notched as well to clear the rocker. Also, on the right, you can see where the bolt boss had to be machined down.


stands on head


rockers installed


some close ups of the rockers. will need the 3/4" spacers to raise the valve covers enough to clear.

AmericanMuscle313

iTrader: (5)

Looks good. Are these adjustable?

mrr23

iTrader: (3)

yes they are.

DONAIMIAN

iTrader: (18)

They look good, but thats way to much hacking of the heads for me.

crazylane

iTrader: (19)

Looks good man, And of by the way, thanks for the great picks, They help out alot.

Lane

Ryan02SS

iTrader: (3)

Very nice. Crane has always made high quality parts as the pics show. That is a good bit of modification to the heads though. More work and over the head of your average LS1 owner. Did you have the heads off when modifying?

speedracer5532

iTrader: (8)

Few things to check/suggestions when installing these. Make sure the stand bolt for the exhaust side isn't too long and bottoms out. I suggest heli coils for every stand hole, aluminum threads get week after bolts have been torqued and removed a few times. These are excellent rocker arms but you have to make sure everything is perfect with the install or you will have problems. I know all of this from experience on my car.

vettenuts

iTrader: (4)

I would also like to know if the heads were off for this, I am assuming they were.

speedracer5532

iTrader: (8)

I really don't see how you could think all that milling could be done with the heads on the car.

mrr23

iTrader: (3)

oh yes, they have to be off the car. all the milling and drilling that has to be done dictates so. these aren't a simple bolt on. i still have to get the 3/4" valve cover spacers to finish up.

mrr23

iTrader: (3)

all of the exhaust ones were fine. about three of the intake holes weren't drill quite deep enough into the runner. so, i had to work that out. it was minor. i hope i never have to remove them again. if so, then i'll look into helicoils.

mr2guru

iTrader: (16)

I am sure they are kick *** rockers... but in all honesty they don't make much sense. Can they be used on trickflows, ETs?, Darts? If not, they are going to have a VERY small market. I would be hesitant to further weaken ported stock castings by taking material off the rocker bosses. They are already close to compromise as the recent issues with TSP has shown in their previous LS6 offering.

If they can be used with the aftermarket castings, whose going to cut their high dollar heads considerably reducing their resale value just to run a set of shaft mounts that aren't significantly cheaper than other proven shaft mounts?

Crane makes good stuff no doubt. But this endeavor just seems misguided when they did (if any) market research for these.

vettenuts

iTrader: (4)

Crane's research was on the rocker geometry, and from what I understand, they could not obtain the correct geometry with the existing boss height. These are definitely a max effort type of rocker, not for the faint of heart. All the reports I have seen indicate a good power boost from them over other aftermarket rockers, including the Crane stud mounted setup.

Mid-lift (Miller) is coming out with LSx rockers soon as well, but they provide a taller rocker boss which is then machined to the head/valve stem dimensions and the cam lift. Again very specific to an application, but their wipe pattern on the valve is extremely narrow and they also maximize lift accelerations in this process.

mrr23

iTrader: (3)

tony mamo cut his high dollar heads to run the shaft mounts. but to answer your question, who ever wants a bullet proof valvetrain and maximize power will do whatever it takes to achieve that goal. i am this person. and there are others. my vhp cnc ported heads weren't cheap to begin with.

mrr23

iTrader: (3)

depends on which market you think they were aiming for. the average person, no. the serious racer, sure.

crazylane

iTrader: (19)

Do all shaft mount rockers require the heads to be worked on???

vettenuts

iTrader: (4)

I looked at Jesels and TD's when I did my heads. All the feedback I had received was that the pushrod holes needed some elongation to eliminate interference and possibly the inner rim of the valve cover surface. I didn't go that route as a result so I don't actually have experience with them and went with Crane stud mounted instead. I really like the stud mounts, but removing them for spring changes is a pain. Full adjustability, especially with the Morel lifters so I can control the lifter preload is a big plus though.