Dialog away my buddy! My personal opinion is that the girdle is not needed for 95% of the nailhead builds out there. That being said I was asked if anyone made one so I asked. Sounds like Rad Rides by Troy has developed one.
Agreed! By the time one is needed, I'd be sure to be in good graces with your machinist as they'd have already made other custom parts for this engine.
Not every engine design benefits from a girdle, too....something to consider. On the BBF site, guys make well over 1000 hp without one, and it's pretty well known that they look really cool hanging on the wall. I've got a wall hanger one in the garage myself, as once I ground off enough to clear the crank in my 4.5" stroke big engine, the supports were the thickness of a toothpick, and the really big hp guys were making fun of me......
I agree not all engines benefit from a girdle... not all hurdles are thin and useless though either... here is my 350 girdle which would not be much different from a nailhead version:
Mine WAS about that beefy haha.....I wasn't saying it's not necessary on a nailhead (that is something I don't know about....what HP and FT.-LBS. is it deemed a good idea on one for my own reference?). Just that not all engine designs benefit from them, no matter what HP or torque you're pushing. Other things will fail before cap walk/block flex comes into play on lots of engines.
I agree, well said... I think a ton of block failures are caused by flexy stock cranks whipping around causing stress on the block... and lack of internal balancing does not help.
The 'girdle' on a BBF doesn't conveniently tie into the pan rails like on sbb or Nailhead. If referring to the halo types out there...there's plenty questioning the design's validity in the first place. The general consensus is that the only benefit is that it keeps your rotator together as one unit 'when' the block lets go. The Olds guys laugh at those too. The FE and BBM (incl. hemi) girdles tie right into the Y block.
Hi all, One for the discussion topic, if you're wanting to stiffen up the main caps, why not make custom ones and cross drill the 3 center caps, similar to the old FE Fords or even the newer LS engines. Like was said it seems most engines that the block doesn't extended below the crank centerline are the ones that benifit most Regards,
Lots of guys do just that, usually in higher power applications. It's a lot more involved than just basically bolting on a main girdle though. If a girdle works, its cheap and easy.
The BBM cap conversion is interesting, too. I've thought about that for the Nail and haven't put much beyond the angled reinforcement needing a skim or counterbore.
Bottom end isn't a problem with a Nail. With it's small valves, you will never make enough horsepower to break the bottom end on a properly set up Nailhead. With it's deep Y block and forged crank, bottom end strength isn't an issue.
The problem isn't the valve size, it's the MCSA in the heads long before that. If I carved up a head from solid stock or cast a new one, you would find some weak links. Definitely a stronger bottom end than many engines larger than it's original displacement range.
I think the turbo or supercharged applications are where the idea of re enforcing the block comes in... yes naturally aspirated the HP levels will not be there.
Maybe Gary the guy who made the sbb girdle can do a run of them? Did you ask him? Anyway, a one off piece(the girdle) won't be cheap whoever makes it for him unless he makes one himself. Maybe a water jet cutting machine company would be the most economical to do a one off girdle but they would have to have a print or drawing to work off of. As long as they have the capability to cut the thickness you wanted they should be able to knock one out pretty quick. With a skirted block, around a 1/2" material should be thick enough if that is the max capability of the water jet shop can cut but some of those machines can cut up to 1" so call around for a shop.
