need help: roller rockers

[Paul619]

I am installing my heads tomorrow and I dont know how to go about adjusting the rockers. They are trickflow roller rockers. can I adjust them without having the lifters pump up or do I have to hot run it? if anyone can help me out before noon tomorrow that is when I am picking up my heads from the machine shop and i wont have acess to a computer, that would be killer.

also do you think the roller rockers will fit under my stock 289 valve covers?

tia

Paul

 

[Ronstang]

Make sure the engine is on TDC. Start with the nunber one cylinder and install the pushrods and rockers loose. On each valve hold the pushrod in between two fingers and move it up and down while slowly tightening the poly lock on the rocker with your fingers until there is no lash. Back off and tighten again if you are unsure. Once both rockers on that cylinder have zero lash use a wrench and go 1/2-3/4 turn more on each poly lock and then tighten the allen set screw to lock them. Turn the crank 1/4 of a turn and do the next cylinder in your firing order. Keep turning the crank 1/4 turn and doing the next cylinder in the firing order until you are done. Finish assembly and start the thing up and enjoy. I only do the 1/4 turn of the crank procedure to guarrantee I am on the heal of the lobes. Some will say there are two positions the crank needs to be in and each one you can do half the valves...but with aftermarket and roller cams I just take the time and go a 1/4 turn at a time.

 

[Clark]

I just installed my cam and lifters last weekend and I agree with Ronstang except for one item. If you are using new lifters that are not pumped up, only adjust the rods so there is no backlash, NO 1/2 to 3/4 turn more. If you have to add some tightening do not go more than a 1/4 turn. I know a few guys that race that can back up that a little loose is better than too tight.

Almost forgot, the stock covers will probably not clear the rockers, you can try and remove the oil baffles but that still might not be enough.

 

[slapper]

It helps if when you are tightening the polylock nut to also let the allen set screw turn slightly as well. Sometimes it's difficult to get enough torque on the set screw with just the allen wrench alone, and we have seen roller rockers back off

 

[67coupe351w]

The lifter needs that turn past zero lash, it applies the preload to the lifter.

If you read this: http://www.cranecams.com/pdf/151g.pdf you will find along with the proper method of installing your rocker arms for both stud (as Ronstang outlined) and pedestal mount. It also shows that a lifter needs .020" to .060" of preload on it. This is applied through the 1/2 to 3/4 (or 1 turn as the pdf file claims...Im partial to 1/2 turn).

Without the preload it is possible for the lifter to blow its snap ring retainer and the lifter would come apart.