Conventional wisdom says roller rockers increase horsepower by reducing valvetrain friction—with the biggest benefits showing up at high RPM. But Engine Masters’ David Freiburger and Steve Dulcich are always willing to question conventional wisdom and will leave no horsepower sacred cow untouched. They’ve tested parts to see what really works, built engines to find the best power-building combination, and explored modifications like cylinder head porting to see if they’re really worth the effort. They do the hard work so you don’t have to.
In Episode 29, David and Steve rounded up a 372 cubic-inch small block Chevy that makes power through 7,000 RPM and put roller rocker conventional wisdom to the test. They tested a set of stock-style stamped steel rockers, stamped steel roller-tip rockers and full roller rockers, and secured them with Lunati polylocks instead of stock-style jam nuts. They even used a set of neato clear valve covers to show the rockers in action.
As is often the case, conventional wisdom is not so clear-cut.
To make things even more interesting, David and Steve tested a set of 1.5:1 and 1.6:1 ratio roller rockers to see if the extra lift was worth any power. You can see what they found by watching the test at:
Engine Masters on the Motor Trend YouTube channel
Rockers Tested
Test 1: Howard’s Cams Stamped Steel Rockers, 1.5:1 Ratio, 7/16″ Stud
Test 2: Proform Stamped Steel Roller Tip Rocker Arms, 1.5:1 Ratio, 3/8″ Stud
Test 3: Scorpion Aluminum Full Roller Rocker Arms 1.5:1 Ratio, 7/16″ Stud
Test 4: Scorpion Aluminum Full Roller Rocker Arms, 1.6:1 Ratio, 7/16″ Stud
Parts List
HRS-90007 Howards Cams Stamped Steel Long Slot Rocker Arms
PRO-66906B Proform Stamped Steel Roller Tip Rocker Arms
SCC-SCP1000 Scorpion Race Series Aluminum Roller Rockers, 1.5 Ratio
SCC-SCP1002 Scorpion Race Series Aluminum Roller Rockers, 1.6 Ratio
ARP-134-7104 ARP High Performance Rocker Arm Studs, 3/8″
ARP-200-7202 ARP Pro Series Rocker Arm Studs, 7/16″
LUN-84380-16 Lunati Polylock Rocker Arm Nuts, 3/8″
LUN-84716-16 Lunati Polylock Rocker Arm Nuts, 7/16″
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Wonderful! I was getting all excited, then……..video not available.
What an anticlimax!
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Read all this and no video ?#!/÷×&
I will admit its a disapointment to say the least but its an other problem got to do reserch to find my self and this is a wake up call to you all its do for your self when it cones to tricks check out route 66 .its how the game is played Personaly it challenges me i like that make the best of it boys and girls they are offering compitition .old school .You all have a great day .
What a piece of crap. Video not available. Video is private. I guess you have to pay some sort of subscription to watch it. What a bunch of Thieving Losers engine masters has become.
Well, from personal experience I can tell you this: I have completely gotten away from any kind of roller rockers! I learned the hard way that a stamped conventional rocker arm will out last ANY roller or roller tip…….PERIOD! “If” there is any horse power loss it’s either negligible or non existent. While I’m at it, I’ve also stopped using any type of electronic ignition systems, as that too, turned out to be both expensive and totally unreliable and unnecessary. I use points exclusively! In fairness, I need to mention that I always set up my own distributors prior to use (curve, slot work, shims, and adjustable vac. adv. etc.). Common sense…..you don’t need 50,000 volts to fire a spark plug. 🙂
Let me guess, The video showed that roller rockers are over rated and Motor Trend took a pay off from the rocker arm manufactures to take down the video?