Adjustable roller rocker problems
 

I seem to have a problem keeping my RRs adjusted correctly on my '89 GT. All of these parts have been on the car since October of last year: E-303 cam which was installed along with new FRPP lifters, old style Twisted Wedge heads updated with bronze valve guides, Crane Energizer 1.6 rocker arms mounted on 7/16" studs, 0.600" lift springs but I don't know what the spring pressures are, and hardened 6.4" pushrods. I questioned the length of the pushrods since TFS recommends a 6.75" length, but the shop that installed these parts for me said that they checked for proper valvetrain geometry with the 6.4" pushrods. These same pushrods were used in a previous car with the same RRs and heads too, so I guess they are right.

A few months after the parts were installed, I started hearing a ticking sound coming from under the valve covers. I tore into it and readjusted them according to the directions on Crane Cam's website, and they were quiet again. About a week later, I went to the track and ran three times with no over-revving or missed gears or anything, and they started ticking again. I went back in and readjusted everything again, but I really made sure to tighten down the lock-nut tight this time. They were quiet for about a week until last night, where I raced a guy two times and now they are making a rattling noise!

I can't keep adjusting these things every week... http://www.mustangworks.com/msgboard/frown.gif I read an article in the latest MM&FF about aluminum heads having a different thermal expansion rate, and how it can cause problems with losing the valve lash settings. MM&FF supposedly cured it with a rocker stud girdle. Am I going to need one for my car too? Does anyone have any other explanations for what could be causing this to happen, or ways to prevent it? If I need to buy the girdle, can someone recommend a quality one? Should I just scrap it and go with shaft-mounted rockers?

Thanks in advance!

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1989 Mustang GT, Charcoal Gray w/Titanium, 80k miles -- Stage III TW heads, E-cam, ported Cobra intake, Compucar N2O, 65mm TB, Kirban FPR @ 42psi, C&L 76mm MAF w/30#'ers, BBK 1 5/8" Jet-Hot long tubes, Dr. Gas X-pipe, Dynomax CVX cat-back, 3.55 gears, Tremec 3550 w/Hurst Comp. Plus, Steeda quadrant, Zoom HD clutch, 16"x8.5" OZ Monte Carlos w/Nitto DRs, Factory Five control arms, SVO pulleys, Accel 300+, K&N, '93 Cobra valance, Auto Meter, 130G<A HREF="http://race.aplus.net/" TARGE