Due to the EU’s Global Data Protection Regulation, our website is currently unavailable to visitors from most European countries. We apologize for this inconvenience and encourage you to visit www.motortrend.com for the latest on new cars, car reviews and news, concept cars and auto show coverage, awards and much more.MOTORTREND.COM
Subscribe to the Free
Newsletter

How to Upgrade LS Rockers Using Summit Racing’s Tool and Conversion Kit

The Quick Fix

Jeff Smith Apr 22, 2015
View Full Gallery

The horsepower game is all about escalation. Everyone knows that the LS engines are the easiest path to big horsepower. But that also means bigger cams and higher engine speeds, and all that puts a strain on valvetrain parts. The stock LS rocker arm is a wonderful piece of engineering. It’s light, small, and very rigid with a 1.7:1 rocker ratio. It’s even blessed with a needle bearing fulcrum. But it’s that stock fulcrum that is the weakest link in the chain. One budget way to improve these rockers is a conversion kit that will replace the stock fulcrum with a more much robust steel piece along with new roller bearings. Until now, the hassle has been making the homemade tools to remove the old parts and install the new ones.

Summit Racing has come up with an elegant tool that solves that pressing problem. Summit’s domestic-built Rocker Arm Trunnion tool is a nicely engineered piece that makes the conversion really simple. Combine that with a Summit LS Rocker Arm Bearing upgrade kit and you can upgrade your valvetrain. Consider that a set of aftermarket aluminum rocker arms for an LS will easily double that investment. This saves enough coin that you can easily justify upgrading the pushrods and valvesprings as well.

Summit Racing Ls Rocker Rebuild Kit Rocker Arm 2/10

01. A great budget valvetrain upgrade for any LS engine is to improve the trunnion strength on a stock LS rocker arm with Summit Racing’s upgrade kit that’s easy to install.

Summit Racing Ls Rocker Rebuild Kit 3/10

02. The upgrade kit includes high-tensile-strength steel trunnions that are mated to a pair of needle roller bearing assemblies and retained by large snap rings. The replacement trunnion is much stronger than the factory piece and greatly increases rocker arm stability.

Summit Racing Ls Rocker Rebuild Kit Removal And Installation Kit 4/10

03. What makes this installation easy is the Summit Racing Trunnion and Bearing Installation/Removal kit. The large black vise fixture is held in place with a pair of very small magnets (foreground). The hollow end cap and mandrel work together to align the needle bearings with the rocker body.

Summit Racing Ls Rocker Rebuild Kit Rocker Arm 5/10

04. With the rockers removed from the engine, place the two small magnets in the holes on the backside of the fixture and position it on the vise. Place the hollow portion of the black end cap over one side of the stock rocker arm and slowly close the vise. This will remove the stock bearings and trunnion.

Summit Racing Ls Rocker Rebuild Kit Roller Bearing 6/10

05. Place a new roller bearing over one end of the mandrel and the hollow end of the black cap on the other. Then place the spacer next to the bearing.

Summit Racing Ls Rocker Rebuild Kit Bare Rocker 7/10

06. Place the mandrel assembly into a bare rocker and press the new bearing into place.

Summit Racing Ls Rocker Rebuild Kit Assembly 8/10

07. Coat both bearings with assembly lube and then slide a new trunnion inside the bearing in the rocker. Slide the trunnion out enough to engage the new bearing and position the end of the trunnion with the large washer. Make sure the trunnion moves easily as you press the assembly into the rocker.

Summit Racing Ls Rocker Rebuild Kit Rocker Snap Ring 9/10

08. Use a pair of expanding snap ring pliers to install the large snap rings over each end of the trunnion and there you have it: an assembled rocker. Summit’s spec is total endplay of 0.005-0.010-inch. Total assembly time is less than 45 minutes.

Summit Ls Rocker Rebuild Kit Rockers 10/10

09. Replacing the rockers is just as easy although this would be a great time to add new springs or at least stronger pushrods. Make sure the flat, spot-faced portion of the trunnion faces up to match the washer on the factory bolt. Torque the factory bolt to 22 ft-lb and the job is complete. With the net lash system, you don’t have to set lifter preload, making the reinstallation a breeze.

Parts List
Description PN Source
Summit LS Rocker Arm Bearing Kit SME-143002 Summit Racing
Summit Rocker Trunnion Install Tool SME-906011 Summit Racing
Summit LS Rocker bearing (2) SME-143002-2B Summit Racing
COMP valvespring kit, beehive CCA-26915-16 Summit Racing
COMP valvespring retainers, steel CCA-774-16 Summit Racing
COMP Hi-Tech pushrods, 7.400” CCA-7955-16 Summit Racing

Sources

Comp Cams
Memphis, TN 38118
800-999-0853
http://www.compcams.com
Summit Racing
Akron, OH
800-230-3030
http://www.summitracing.com

MORE PHOTOS

VIEW FULL GALLERY
X

Connect With Us

Get Latest News and Articles. Newsletter Sign Up

sponsored links

subscribe to the magazine

get digital get print
CLOSE X
BUYER'S GUIDE
SEE THE ALL NEW
NEWS, REVIEWS & SPECS
TO TOP