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Discussion Starter #1
This doesn't affect very many here but I thought I would post it anyway.
I have been running a stud girdle on my motors for the last 20 years. I thought it was a good idea at the time but now I wonder.
I run 200 pound springs on the seat and 550 pounds open.
I spent the weekend setting the valve, I am running out of work, the 540 is just about ready to fire. The car other then plugs and timing is done.
I set the valves very carefully, recheck 2 more times and then install the stud girdle. I then recheck very valve 2 more times and found a number of clearances very carefully set before are suddenly way off. It can tighten , and I found they tightened rather then loosened. They tightened up to .010.
I spent an entire day reworking the stud support one hole at a time. Using feeler gages and eyeballing I would modify one support, reinstall, check clearance with the girdle tightened down and move on to the next.
Is a girdle really necessary? If not custom fit do they do more harm then good? I don't know but it is done now and with everything snugged up the clearances set before remain the same after installing the girdle.
This is an old old shot. Not my new 540
 

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My opinion is somewhere in the worthless range, but I can't see using a stud girdle unless you're breaking parts. I'm running the ZL-1 factory cam, 7/16 studs and 7/16 pushrods, factory long slot rockers and my valve lash rarely changes. I think if you're running a real big time roller cam with quick ramps then maybe. But then I'm not trying to wind it over 7500 either. It will go, but pucker factor takes over.

I suspect what you're seeing is setting the lash, then when you install the girdle it's pulling the rocker studs. If you can get past that you should be good.

:thumbsup:
 

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Discussion Starter #3
All opinions are welcome. I can take it or leave it. I have corrected the problem. The stud girdle was bending some of the studs over and changing the valve lash when tightening the girdle clamps.
You are probably right, I don't need a girdle.
My cam for the size of the engine is not that big but agian in a 454 it would be very large. It is 265/270 @.050 with a low lift of .630 I didn't want high lift on a street machine. The springs again for a normal street machine are fairly high at about #200 seat and #550 open.
I had the stud girdle in the shop, not something I went out a bought, well not in the last 20 years and once modified it should hold the studs securely at the top and no longer moves the studs when tightening it down.
Anything free standing up in the air has got to be helped
by putting a bunch of braces from the top down. It just makes the post more rigid and that transmits into a steadier valve train.
 

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Good post. Can you install the stud girdle before setting the valves and just
loosen it enough to adjust each nut one at a time?

Some people swear by these if you are going to run high RPM's.
 
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