ih8chevy

no

Chitown racer

Well your right at the borderline of where I usually recommend using these, but yes that do work. Nothing can make your block bullet proof but they sure help hold it together longer. First of all let me put to rest this festering piece of misinformation about the intake manifold working just as good as "valley girdles", the fact is they dont. When you consider that CastAluminum and Cast Iron expand and contract at different rates when heated and cooled. Then you add the fact that the heads are bolted to the block, then the intake is bolted to the heads, and that in between them thierare gaskets. Gaskets that are designed to allowa very small amountmovementbetween those "veryparts" under load, thiers no way the intakewould be able tosupport the block.Now how can this obviously, very small amount of movement cause harm you ask? Well when you stress the block to its structural limits this very small amount of movement becomes enough to allow stress cracks to form in the weak areas of the block. Then with repeated abuse those stress cracks quickly lead to block failure. The reason these "valley girdles" work is theyare "directly attached" to the block and directly effect the amount that the block is allowed to flex under stress. Furthermore, if they werent necessary then why would aftermarket blocks come with the lifter valley supports cast into them? The fact is they wouldnt, they werent needed I'm sure the aftermarket companies would jump at any chance to make thier block lighter. Also, if the intake manifold was such a support piece then why wouldn't companies like Edelbrock and Trick Flow make manifolds with supports cast into them and taken advantage of what would be an obviously huge selling point, why? Cuz they know that any "real" engine builder, not "internet" engine builder, knows it wont work. That they would be laughed out of business for trying to sell them. I'm glad we got that cleared up and I hope that answeredmost ofyour questions about "valley girdles" vs Intake Manifolds.

Now back to the originalquestion, yes I would recommend them in your case. They would be excellent insurance and if you decide to make more power later then your block is as strong as you can make it.

ruger311

NO!

fordstroker

If they worked I along with many others would have used them 15 years ago.[:@]

r.barn

stud girdles are good for high rpm engines to help stabilize the crank shaft.
if you're only running 6,500rpm they're a waste

Valley girdles are a waste too. If your lower intake cant hold the block together
a couple small strips of metal running across the lifter valley are not going to do anything either.

d_och23

are u talking about the main girdle or the girdle for the lifters??? id rather invest in the main girdles.

nick_thames

they are kind of like a roll cage for your motor. They add stability. Im buying them for my 347 project that im working on. Also im buying the main girdle for the bottom end. They were talking about 600+ hp on a stock block. I say anything you can do to help your block last a little longer is worth the $400 to put them both on. Besides, you can then bolt the windage tray right on the main girdle and that will help with lost power.