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As I'm waiting for my heads to come back from the machine shop who are doing a proper 7/16 stud conversion, I'm shopping for rockers and would like to get recommendations. I was ready to get the Comp Cams Ultra Pro Magnum XD https://www.summitracing.com/parts/cca-1830-16
Then found out they're made "offshore" (China?) now.
Same with the Comp Cams Ultra Gold.

For US made rockers (without spending $800 on Crowers) it seems the choices are Scorpion or Harland Sharp. I've read of a number of Scorpion snap rings ending up in oil pans so Harland Sharp seem to be the way to go.
I know Yella Terra are also highly regarded but I'd like to stay under $500.
Any input would be appreciated.

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Don't know how their quality is nowadays, but I've had Harland Sharp aluminum rockers on our 351-C for nigh-onto 30 years with no complaints. Don't expect a horsepower advantage with any roller rockers. The advantage is in less friction so lower oil temps on long runs, and prolonging valve job life. They are also rebuildable if necessary.

Aluminum works fine with lower valve spring strengths & 6000 redline and cast steel for stiff racing springs & 7000-up redlines. I also run stud girdles and recommend them. Good insurance against broken studs and  the girdles hold the adjustment nuts against slipping. The Ridgeways on our car is out of business but Jo-Mar is very similar.

The girdles are a $200 insurance policy. Things like rocker studs do break (often from over-revving). One guy with stud girdles broke a stud at an open track event in 'Vegas, and drove back home 200 miles to L.A. with what he said was a 'tired engine'. Another without a girdle did exactly the same another year, but after working on his motor all weekend with borrowed tools (while others were partying), finally called a tow truck for the same 200+ mile trip. We didn't see him again....

Because they are bulky and interfere with valve adjustment, they are especially  recommended for hydraulic (roller) cams that do not need much adjustment. Several shops sell Jo-Mar #1135 for the obsolete  Cleveland. They fit under cast aluminum rocker covers if you discard the removable baffles.

Sharps are good. So are "Ford Motorsport/Racing". Compcams are on that list too.

I personally think that with 7/16" studs, girdles are overkill. I have never broken any although I have bent push rods.

Hydraulic roller cams, because of the increased spring pressures might be a good application for a girdle though.

I'm old school. I like solid lifter cams because of the lighter weight of the valve train and the ease of adjustment.

I'm running Compcams stainless rockers in my Pantera and shaft rockers in my 347.

Those make the engine sound like an electric motor at speed but are certainly over kill.

With solid rollers, I worry about shedding those little needles in the engine like my friends used to do, unless you run bushing lifters like Isky. Plus I've gotten lazy these days about painful lifter adjustments (I always did mine hot) and just stay away from the redline. That, the usual adjusting, and shaft rockers all make the girdles less desirable unless you go for locomotive valve springs. SS rockers are bullet proof as are bushing lifters, and T&D are just a few miles from my house.

@jmardy posted:

Thanks Boss.
I've ordered the heavy duty versions:
https://www.summitracing.com/parts/csp-sh4005

Will put the stud girdle on the list after I've recovered from other expenses.

I've got a slightly used (~200 miles) set of Crower Stainless Steel Enduro's if you're interested. I was talked into T&D shaft rockers by my engine builder, so I don't need the Crower's. $375 for the set + shipping from Northern California.
*** SOLD ***

Last edited by davidnunn

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