That's very true. I used the Comp Cams Magnums on my 400 only because they were actually cheaper than buying a whole new set of stock type rockers. Now using roller rockers as part of a complete roller valvetrain makes more sense for maximum performance but all by themselves it's not going to net much more power. They look cool tho'!

 

Piston and ring to cylinder wall friction is still the biggest power robbing point in the engine. They don't seem to be able to do a lot about it tho. My Ertel pistons have a special machined in surface finish that is supposed to help but I still wonder about long term performance gains. There are ceramic and teflon coatings also but how long do those last??? Racers use low tension oil rings but pay for it with increased oil consumption.

I have a complete roller valve train for my engine but I was patient and picked up the parts cheap. Buying the parts outright is big $$$.

 

If you read literature from many Roller Rocker Arm manufacturers, they state minimum average gains of 15-40 hp, and I can honestly say these are very much true. They also lighten the valve train allowing increased rpm potential, and a more stable power curve, along with decreased oil temperature.

 

Comp Cams states that using their Magnum rockers can net a 15-30 HP gain despite the fact that they're not even a true roller system (they only have a roller tip not a roller fulcrum). They claim it's from reduced friction at the valve tip as well as a more precise valve lift.

Comp Cams catalog

I'm not sure I actually believe them however. Like I said before I bought them because they were cheaper than buying a new set of stock type rockers.

 

That's fine, but Harland Sharp full roller rocker arms are worth upwards of 40 hp, and it is a difference you can truly feel. Factory rocker arms are not worth the money or time to locate and buy.

 

I have a set of FMS on my 400 I picked up at a car show(saved about 80 bucks)
I see lots of stuff here I agree with. yeah, I noticed a broader range of power, tighter tolerances and it was an easy bolt on.

but when you first start the engine after the swap you can really hear the engine running. its like you took off all the accessories and belts. anyone who spends the time fine tunning their engine can relate to that. they just make the engine run better. next engine I build for myself will be an All Roller Motor.

 

I bought a new set of stock-type rockers on the 'bay for 9.97 plus postage. Bill, want to trade for your rollers???
R.

 

All of those competing claims, charts, graphs, etc, etc, is why I use the 20 lb-ft of torque figure. It might be a little conservative but I like to error on the conservative side.

 

Roller Rockers are easier on your valve guides. Over a period of time they will pay for themselves by not needing to replace valve guides.