I am looking for some guidelines. What determines that stud girdles should be used on a valve train? Is RPM a factor or is it lift related?

Thanks,
John Winkeler

 

We normally go by spring pressure and lobe profile. Lift is going to effect both of those, but in and of itself I wouldn't worry about it directly.

Generally though with the more agressive solid setups we like to run a stud girdle - we generally end up using them when we go with pacalloy springs.

 

I just as my engine builder what he thought. His answer was, "If the rocker studs are tapped correctly you should be able to lay a straight edge and everyone will be touching. After you install the rockers and adjust the valves, if the pressure deflects any tops of the studs more than .030 your in need of a stud girdle, bigger studs,........"

So the above poster was right.

 

So I guess you really don't know until you assemble the head.

I am looking at running 7/16 rocker studs and running the comp cams 977 springs (spring rate of 441 lb/in, which seems to be lighter than the Pacalloys which seem to start around 500 lb/in and go up to 700+ lb/in). These facts seem to indicate that I will be ok without a stud girdle.

Thanks for the pointers,
John

 

I use the crane gold stud girdle. Don't even mess with the cheapos. If you have springs like that and a roller cam with over .550 lift your going to need one or a least it's added insurance.

 

I would recommend everyone who has any kind of valve train 'work' done or planned for the future...include stud girdles with their modifications. (Don't go buying yourself some pretty valve covers in the 'stock' configuration, until you've figured what kind of 'height' you're going to require to clear any and all additions). It could be a waste of money. Read on.

I'm convinced, the stud girdles I'm using (JoMar) although they require some machining in order to get them to work, they are an awesome piece of engineering marvel. I have Trick Flow Center-Bolt Heads. I'm telling you, my engine feels (seat of pants) so much 'tighter', and my valve adjustments, which used to be required every 1500 miles or so...I've now gone over 3,000 miles, and it's still as strong as I hoped it would be after doing this modification. No additional adjustments thus far...which is great news for those of us who have this requirement.

Keep in mind...depending on what type of head you're running (stock vs aftermarket)...you may have to go to TALLER valve covers when using a stud girdle.

If you are running Center-Bolt Heads, and plan on using Stud Girdles now or in the future...remember this name when you find yourself requiring TALLER valve covers (Melrose).

They have quality covers, that are thick, and 4" TALL from the inside down. In addition, because of the quality of their covers, the valve train 'noise' is nearly impossible to hear.

Just my two cents. Good Luck!!