so heres my newest problem. because im trying to compete in 2 different clubs, one does not allow roller or roller tipped rockers, im pushing past the limit on the stock rocker arms. they wont stand up to 670# open pressure and 7000rpm. I order one crane nitro-carb rocker that are supposed to be stronger than stock but im not sure if they will clear my big retainers or not.
http://www.cranecams.com/?show=browseParts&lvl=3&prt=105&action=partSpec&partNumber=13801C-16

Ive only made 3 real hooks with these. one was on a real tight track and turned 6200. the next was on a really loose track and i would say turned 7000 and backed out of it some, tach went haywire, i broke one rocker on this hook. then I pulled at the pa power pull in an street open class with some reall heavy hitters. finished 9th out of 21 trucks but the truck didnt come to life like it should have so i shut it down at the end of the track and got a tow. the next morning i pulled the valve covers to find 3 more rockers broke. both on number 8, but they hadnt shoved the 3/8 part thru yet so they were holding the lifters in, and one on number 2. so 9th wasnt bad on 6 cyl as i watched the video afterwards it barely spun out at the end but the truck hooked well so atleast something went right.




btw theres lots of clearance everywhere with this style of rocker. and i made a set of fulcrums out of 1 1/16 O-1 so they are no longer the weak link

Summit # CRN-13801-16 Stamped steel rockers. I put these into my dads truck Cuz we where having troubles with the Ford stamped rockers busting the fulcrum. So far we had one push the push rod thru the cup But I'll try them for a while longer before I switch to something else.

Daddies cam numbers
Dur. @ .050 248 254
Lift .654 .661
Lobe Sep. 112


Dan

i ordered a single one of those yesterday to try and see if i have enough clearance with them. im running the cam i got from you with comp 26099 springs. 245# seat 670# open. if they fit im going to order a set of those nitro-carb ones there another $50 but are suposed to be 3-5 times stronger but who knows. i love how they are trying to make the class afordable with these no roller rocker rules but i can get rollers cheaper than stamped steal. its such a wash.

Cory

Ya there always trying to keep the cost down ...they just don't know how much it $$$$ cost to keep it cheap.



Dan

Those spring numbers are what you run on a roller.

Is it a roller cam?

If it isnt I would love to know how you are not wipin out the cam n lifters with that kinda spring pressures?

yeah ken its a roller cam 270 280 @.05 .740 lift. its helping feed a 466 thru a set of unported iron cjs, rules requirement, so far ive taken 2 first with it and 9th in an open street class with 3 broken rockers. i thru a set of rollers on it for now since my next 2 pulls i can run them at. then ill have to switch them back to something else.

Cory

allow the roller tip type rockers?

They are a soid body steel with the regular fulcrum, and a roller tip?

They work well if so.

i wish they did
but heres the rule

Rocker Arms: No roller or roller-tipped rockers.

heres a link to the rules
http://www.nwpapullers.com/page3.html

an old set of cast rockers from pre 72 will stand up, they appear to be rather beefy around the fullcrum and use a ball socket.

You would need to clearance the stud slot though so you didnt get bind

i though about them but the fact that they are cast makes me wonder. if the break it will just shatter into a 100 pieces and go all over the place

Any chance you could weld in some additional steel on the top side of the rocker to beef it up? Just a thought.

Alan

that was my firts plan but after i did some investigating and found that it wasnt the rockers splitying apart that broke first. the cup pushes thru and then when it comes to the point on the pushrod where it tapers to 3/8 it splits them. I havent tried it yet but i think it will also ruin the heat treat and make them way to soft.

Cory

you could use a BBC rocker as they are the same ratio and stud, and quite heavy

Cory, I know Dan was having trouble with Rockers on his Dad's truck with the same rocker you are running. I sent him a set of cast ones but I don't know if he used them yet.
Maybe he has more ideas if he got them to live in his Dad's truck.
Then like Ken said the other brand rockers will work. Man I hate to admitt it But years ago when I was young and dumb I ran a set that were the long slot style. But of course they were not subject to your spring rates either.

thats what the crane ones are for and i think theyll work as lonk as i have retainer clearance

What class rules do you go buy ? street or high performance the street rules say any hydraulic cam.

I run the street class. I should have specified. and the cam uses crane hydraulic roller lifters.

Cory