Guest Frank280z Posted September 18, 2000 Share Posted September 18, 2000 I'm using Comp Cams Magnum roller rockers with a 1.5 ratio. I am getting a little too much noise from them. What is the proper way to adjust them? I misplaced the install sheet. Thanks Frank ------------------ Build it. Drive it. Improve it. Quote Link to comment Share on other sites More sharing options...
Guest Fast Frog Posted September 18, 2000 Share Posted September 18, 2000 Frank: Tighten the stud nut until you have zero lash (not easy to turn the push rod with your fingers with oil on the rod). Then turn stud nut one complete turn and lock down. I've done it with a micrometer to get .040-.060 pre load and I've done it with the engine running(real messey). This seems the best way to do it . The noise factor should sound like Mom's old Singer sewing machine. Rick Quote Link to comment Share on other sites More sharing options...
John Scott Posted September 18, 2000 Share Posted September 18, 2000 Good choice on the Magnums! Light and strong. Again I'll add to Frog's technique. Make sure the cam is off the lobe and on the base circle. Loosen the adjusting nut so the push rod has play in it. Spin the pushrod between your fingers as you tighten lock nut. When it just "grabs" and becomes harder to turn you are at 0 lash. Then give your preload, anywhere from 1/4 to 1 full turn. Adjust intake when the exhaust is just starting to open. Adjust the exhaust just when the intake is starting to close. On a real healthy cam some run as little as 1/4 turn, but will be more noisy. I usually run 3/4 and have no problem seeing 7000+ rpm. 3/4- 1 full turn is the standard set. Mine are slightly clicky, anyway more so than a standard rocker. JS Quote Link to comment Share on other sites More sharing options...
Modern Motorsports Ltd Posted September 20, 2000 Share Posted September 20, 2000 After changing rockers/setups a number of times now I've been told and become a believer in 'hot' adjustments on hydraulic cams as the ONLY way to get it dead nuts right. Cold adjustments can get it v. close (w/ odometers even more so, but hot is done a lot faster by myself) but I've still found upon doing my HOT adjustment some are slightly too tight and some too soft. You don't want any too tight (bent pushrod) and if they're all the same it's smooth=>balance=>power. I go 1/2 turn for summer/racing and 5/8-3/4 for winter/street. Below URL will clear it up. Find an old valvecover and cut out the top so you can access your adjustment nuts. warm up the motor, remove one valve cover (have towels handy, things are HOT). Install 'open' valvecover, start up engine. Have your adjustment tool ready (proper tool with both allen and open wrench expedites this) and slack off on one lifter till you hear an audible clicking, may already be clicking and only get louder or take a turn or two to get it 'clicking'. Once clicking tighten slow till noise just ends (fairly audible) and go your 1/2-3/4 etc. I go 3/8's with wrench only and then last 1/8 with wrench and allen (had snugged up allen key after 3/8") to v. positively lock the adjustment. Below will clarify it more. Here's a fine URL for techinfo http://www.centuryperformance.com/valveadjustment.htm Quote Link to comment Share on other sites More sharing options...
John Scott Posted September 21, 2000 Share Posted September 21, 2000 I would agree that a hot running engine is the way to go. Those of us with obnoxious things like superchargers in the way of the valve covers have to rely on the other method. (I adjust after a good warm up)Since we're dealing with hydraulic lifters either way will be acceptable. Solids lifters are another story. JS Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.