Do main cap straps help?

 

I think the biggest benefit is adding rigidity and some stability to maintain concentricity. From what I have been told the caps are fairly soft.

 

The only problem with them is milling 1/2 inch off mains to fit them. Stud the mains and make sure your machine work is good. Otherwise a 5 cap or better girdle. Better yet a Rocket Block.

 

With Rocket Racing still selling the cap straps, I assume they do some good to help pull a more even pressure load across the main cap's surface, vs. just studs into the raw main cap.

Our current build engine runs cap straps.... do they help?

I dunno, haven't tried building one without main caps, ever.... every 455 build we have done has had these cap straps, at all power levels.

I truly wish I could reach up and start a new Rocket Block Build myself.... just don't have the money to do it for a loooooong time, if ever.

 

From a structural standpoint, the straps that go across the main caps are less than worthless. First, the cap itself is stiffer than the strap, so the strap adds nothing. The load will always go through the stiffest path. Second, any clearance in the bolt holes results in compliance that further makes them worthless. These straps have zero actual engineering behind them.

 

Joe, I won’t argue the engineering side of this, you’re far more educated on that than I am.
However I would argue the material strength difference. There’s no way a cast or even Nodular cap is stronger than the steel these straps are made of. They’re quite hard.

 

Mark,

It isn't a strength issue, it's a stiffness issue. If the cast iron can deflect before the strap picks up appreciable load, the strap does nothing. And is the concern really breaking the caps, or is it keeping the bearings round? I'm guessing it's the latter, in which case the straps are like TSA - they provide the APPEARANCE of security.

 

Best upgrade for a stock 455 bottom end would be the ARP studs instead of the bolts.

Ideally the Rocket Racing block is an engineering improvement with its 4 bolt splayed mains and stronger billet metal caps.They claim 2,000 HP levels on that block.

 

If I'm not mistaken, Pro Gram made steel caps. Those, and studs, should be good. But, I got one of those halo things, too.