Always wondered.....

[bigcam406]

Good day folks. I was going through some old photos of my 69 Camaro I picked up back in 1995. The previous owner was a young man who was desperate to get rid of it. When I went to see it, he didn't know much about the 355 small block that the previous owner before him had installed in it. When I purchased it, I had to basically play detective and remove the front of the engine to get to the cam. I got the grind number off of the cam and it was a large Crane Saturday Night Special hydraulic with over 250 degrees @ .050 on a 106 LSA. What puzzled me was there was a Jomar stud girdle with Harland Sharp roller rockers on a set of ported Dart 2 Sportsman heads. My question back then was why would you need a stud girdle for a hydraulic cam that is RPM limited? No one back then could give me an honest answer as to why. When I was checking out the pictures, the question popped back in my head after 27 years. I know...weird thing to wonder about after all this time...

[RW TECH]

I wouldn't just automatically assume that it was RPM limited because it was hydraulic.

I have worked with hydraulic roller systems that would spin clean to about 8,800 RPM on a spin test rig with lift loss that was comparable to what would normally be seen with some.solid rollers.

[Ken_Parkman]

Many things are done because they look cool or someone told them it's a good idea. Often not related to good functionality.

[FC-Pilot]

Stud girdles are cool and look racie. Some see them in a book, magazine or the performance parts shop and need to have them. I have put girdles on hydraulic cams before when I just wanted to make sure I did not have studs flexing while running decent rpm with a hydraulic lifter cam. Overkill, but gave me some piece of mind. I also have a brother that wanted them on his hydraulic cam as that way he knew he would not have a rocker back off on him (those were his words). Anyway, that is three reasons right there, and I am sure there is even more than that.

Paul

[1980RS]

The only time I ever run a stud girdle is with a large solid lift cam and mostly on Roller cams. I have found with using them my valve lash stays better in check. On a street car with a hyd cam not needed IMO.

[bigcam406]

The only time I ever run a stud girdle is with a large solid lift cam and mostly on Roller cams. I have found with using them my valve lash stays better in check. On a street car with a hyd cam not needed IMO.

That's the idea I was having at the time. When I first initially removed the valve covers I thought it must be a solid flat tappet. Then I checked the grind number and thought what the heck.
I appreciate all of your responses, like I stated earlier, its weird what pops into your head sometimes. Unfortunately I had to sell the car a number of years ago, but its nice to reminisce about the good times I had with that vehicle. Many thanks.

[PackardV8]

Very few projects are clean-sheet well-thought-out builds.
Entirely possible the heads were left over from some race car project and were used with the soupy cam just because he had them.

[jeff swisher]

I have built many flat tappet hydraulic SBC engines that would spin past 7500 rpm and I used 7/16" studs in most of them.
Take some 3/8" studs and I would like something to make them a bit stiffer.

And like mentioned maybe that stuff was already on hand.

[lefty o]

even tiny little factory cams flex 3/8 rocker studs.

[steve cowan]

even tiny little factory cams flex 3/8 rocker studs.

Yes,
And possibly the OP- SP2 heads had 3/8" studs??hence the girdle.
I think spring control dictates if lash moves.

[Walter R. Malik]

The only time I ever run a stud girdle is with a large solid lift cam and mostly on Roller cams. I have found with using them my valve lash stays better in check. On a street car with a hyd cam not needed IMO.

Using a stud girdle may not be of any help but, it certainly won't be a detriment at any time to anything with a stud valve train.

I have witnessed some very, VERY aggressive hydraulic lifter camshafts; especially some high lift hydraulic rollers.

[jsgarage]

There are two reasons to run a stud girdle on a hydraulic lifter engine. One is to reinforce flexing studs and allow one to drive home if a stud breaks- for any reason. I do not like riding in tow trucks. The second is to positively clamp the valve lash adjusting nuts so your set clearance doesn't change. Call it insurance and/or an alternative to shaft rockers.

[bigcam406]

There are two reasons to run a stud girdle on a hydraulic lifter engine. One is to reinforce flexing studs and allow one to drive home if a stud breaks- for any reason. I do not like riding in tow trucks. The second is to positively clamp the valve lash adjusting nuts so your set clearance doesn't change. Call it insurance and/or an alternative to shaft rockers.

Thanks for the replies. In guessing it was installed for reliability sake. Makes sense to me now.

Thanks again.