I was digging through old posts last night, and someone had mentioned using 3.1L rocker arms on an SBC? I can't find the post now (go figure), but I just wanted to clarify:

my factory '82 LG4 would have "normal rockers" as opposed to rollers right? and upgrading to roller rockers requires no special items right (aside from just the rockers, i'd be swapping the cam at the same time anyway...) but could I use roller rockers? I understand i'd gain power due to less friction correct?

My main question is, since roller rockers are fairly expensive (and I don't even want to start on aluminum vs steel), is it true that some factory blocks (ie. the 3.1L ?) used roller rockers that are interchangeable with mine? And would they be worthwhile? (assuming they are dirt cheap from the wreckers)

Thanks -J

 

The 3.1L thing is using the lifters, not the rockers. Its supposed to be one method of making a roller motor.

 

a roller motor would be
roller cam (which is pricey, and requires roller lifters right?)
roller lifters
roller rockers ( doesn't require the previous two right?)

So lifters from a 3.1L are usable? (worthwhile to go with a roller cam?) but only if I obtained a roller cam to go with it right? Are roller rockers available/usable from a junkyard motor, or should I spend the coin on aftermarket ones?

 

When the name "roller motor" is used, the rockers are not part of that "roller" in reference. The roller being talked about is the mating surface between the cam and the lifter, that's it. But yes, you are correct in saying that the fact that rocker arms have nothing to do with the fact that the tappets are roller or flat tappet. You are also correct in saying a roller cam requires roller lifters. Both the materials used (Steel versus cast iron) and the way the lobes are profiled differ. (flat tappet cams are ground with the lobes on a slight angle to spin the tappets in their bore, whereas rollers are not).

No factory Gen. I SBC got roller rockers, either roller tip of full trunion. GM blessed us with those stamped rubberized POS's. But yes, roller lifters will fit in the bore as both are the .842" diameter. I know it's been acomplished before, maybe try a search and see what you can't rustle up.

Have you tried looking on eBay or something for used retro-fit roller lifters? Might want to try that before you go drilling and tapping your block.

 

yea, that's another thing I was wondering, a roller block is one already set up for roller lifters (and roller cam), and mine, ('82 LG4) would not be. What is involved in swapping to a roller cam? A retrofitted cam and lifters, some block machine work?
Is it worth the investment? what would be the gain in going to a roller rather than flat tappet cam?

In my case, this is assuming the motor will be getting other bolt ons, headers, home-ported stock heads, intake etc.... and will be used on the street, probably never above 6000RPM.

 

A retro-fit roller setup requires absolutly no work to the block. Just slide the cam it, drop the lifters in, attach the link bars and button the rest of.

Roller cams always out perform flat tappets of smilar stats. The roller design allows for more aggressive ramp rates. Also, there really isn't much chance of screwing up a cam break in as roller lifters/cams don't require break in's.

In my opinion, for a warmed over street engine, either will do fine. If you can find some retro-fit hardware on eBay, go for it. Otherwise, it may not be worth the chunk of change to convert to a roller.