proform roller rockers

[oldsnofear]

Hey I just put on my new proform roller rockers. the 3/8 pushrod rub on the heads. Im having smith bros build me some 5/16 ball/cup pushrods. this is pretty much a stock build but the machine shop recomended i go with adjustable do to the valve heights.I plan on putting on 12000 miles a year and want no problems any tips? this is a stock  383 and it is detailed perfect (thats why i dont want to pull the heads off to grind them) also it seems the roller tip is not perfectly centered on the valve stem WTF any help would be greatly appreitied thanks Shawn

[firefighter3931]

Hey I just put on my new proform roller rockers. the 3/8 pushrod rub on the heads. Im having smith bros build me some 5/16 ball/cup pushrods. this is pretty much a stock build but the machine shop recomended i go with adjustable do to the valve heights.I plan on putting on 12000 miles a year and want no problems any tips? this is a stock  383 and it is detailed perfect (thats why i dont want to pull the heads off to grind them) also it seems the roller tip is not perfectly centered on the valve stem WTF any help would be greatly appreitied thanks Shawn

I would return those rocker arms. From what you are describing the valvetrain geometry is all wrong. The crane ductile iron rockers allways fit well and are indestructable. 

Unless the valve lift exceeds .520 you can get away with the factory non adjustable rockers. With stock heads, anything over .510 lift requires mods to the valve guides...hopefully your shop fixed this for you and specced the correct valve springs for the application. 



Ron

[chargerbr549]

We just installed a set on a guys stock iron headed 400 and I wasn't impressed with where the roller tip sat on the valve stem, it was way to the inside but that is what the customer wanted to use.

Kevin

[oldsnofear]

MY ROLLER TIPS ALSO SAT ON THE INNER HALF OF THE VALVE STEM. DO THE CRANE IRON DUCTLIE USE A STOCK 5/16 PUSHROD? MY 3/8 FROM CRANE RUB THE HEADS PRETTY GOOD AND  I DO NOT WANT TO REMOVE THE HEADS. THANKS FOR THE HELP

[firefighter3931]

MY ROLLER TIPS ALSO SAT ON THE INNER HALF OF THE VALVE STEM. DO THE CRANE IRON DUCTLIE USE A STOCK 5/16 PUSHROD? MY 3/8 FROM CRANE RUB THE HEADS PRETTY GOOD AND  I DO NOT WANT TO REMOVE THE HEADS. THANKS FOR THE HELP

The Crane ductile iron rockers use a ball/cup pushrod just like the Profroms....not a stock ball/ball pushrod.

I would try using the 3/8 pushrods you have first before ordering the 5/16...they will probably work. The problem with the PF rockers is that they are too short from the fulcrum to the valve tip roller which will cause a less than desirable sweep pattern across the valve tip. A bad sweep will accelerate valve guide wear amongst other things....it's not the right way to go. 


Also, when sizing the pushrods you want 1-2 threads on the adjuster screw showing on the bottom of the rocker arm. This is for proper geometry, strength and oiling. Set the lash or preload and look at this closely. 



Ron