half shaft guard

[keywestjack]

Has anyone designed or used a device to limit the damage if a u joint breaks either on a drive shaft of half shaft. Seems to me someone had one or was thinking about installing one after his broke and did some damage.

 

[MYBAD79]

Yes, it's called a safety loop. Dragvette is one of the companies that offers a "kit" - I have no first hand experience about fitment and quality.

I would think you could just bolt the loops to the strut rods and maybe add a brace that you weld or bolt to the crossmember - I think this is relatively simple and these are on my 'to do' list as well....

 

[Red]

If you maintain strong u-joints and apply moderate HP, the half shaft safety loops are not necessary IMO. They are cheap insurance if you worry about it. That said, this is a picture of the Drag Vette half shaft safety loops

This is a safety loop made by a racer for his C-3

[/IMG]

 

[MYBAD79]

This is a safety loop made by a racer for his C-3

thanks for the photo, I never thought about simply welding it to the crossmember.... $50 for a universal set from Summit, very cheap insurance indeed :thumbs:

It's not just the U-joints, these old half shafts can twist and snap at the tube....

 

[Red]

This is a safety loop made by a racer for his C-3

thanks for the photo, I never thought about simply welding it to the crossmember.... $50 for a universal set from Summit, very cheap insurance indeed :thumbs:

It's not just the U-joints, these old half shafts can twist and snap at the tube....

Of course you are correct, but with moderate HP and street tires, twisting good half shafts is unlikely. Throw 450+HP and slicks into the equation and failure to add loops becomes foolish. As far as I know, back in 68 all the BB engine options used the standard 2.5 inch diameter half shafts. Drag racers with built motors must have used reinforced shafts to hold the torque, but I have not read about this as a common practice. An L-88 with 2.5 inch shafts 500+ HP and street tires of the day would not have been a problem. Add sticky slicks and now it is a matter of when the shafts twist.

The welded loops is a good option, especially if they are bolted to tabs welded to the frame. It then becomes much easier to remove them when necessary and work on the car. The Drag Vette loops are a nice design and idea, but more difficult to remove, because of the shock mount, if frequent dis-assembly becomes necessary. I suppose it is a personal choice and judgment call.

 

[SmokinBBC]

I put the dragvette loops on mine. I guess my HP range on the BB is somewhere around 480HP. Torque is upwards 530. The loops were easy to do.

I also have the dragvette driveshaft loop which I haven't installed yet. I was more concerned about the driveshaft since the ujoint straps are just straps whereas the halfshafts on the BB have ujoint caps. Although, I haven't heard of the straps going, they just look too flimsy. I haven't figured out what to do with the parking brake cable since it would be in the way of the halfshaft loop which goes into the crossmember(loop is just rearward of the the ujoint after the trans output shaft).

 

[Red]

I put the dragvette loops on mine. I guess my HP range on the BB is somewhere around 480HP. Torque is upwards 530. The loops were easy to do.

I also have the dragvette driveshaft loop which I haven't installed yet. I was more concerned about the driveshaft since the ujoint straps are just straps whereas the halfshafts on the BB have ujoint caps. Although, I haven't heard of the straps going, they just look too flimsy. I haven't figured out what to do with the parking brake cable since it would be in the way of the halfshaft loop which goes into the crossmember(loop is just rearward of the the ujoint after the trans output shaft).

I spoke with Steve at Drag Vette about this same concern. He said the DS U-joint, U-bolt straps were never found to be a problem with failure. There is way more stress on the half shaft u-joint, u-bolt straps, so the BB caps are recommended for HP applications. It is important to not overtighten the u-bolts in DS,or HS, as they can deform the cap and result in premature failure. Tighter is not always better. Factory torque specs should be followed, I believe it is 18 lb/ft.(refer to your manual)

Generally, unless your differential yokes were drilled and tapped for the screw in u-joint BB caps, u-bolt straps are used to hold the u-joint caps. I believe there are BB type caps available with studs, so you can get the same support as the BB caps with no threads in the yoke. I do not have any experience with them, just mentioning them as an item I remember seeing in a non Corvette specific catalog.

 

[SmokinBBC]

I put the dragvette loops on mine. I guess my HP range on the BB is somewhere around 480HP. Torque is upwards 530. The loops were easy to do.

I also have the dragvette driveshaft loop which I haven't installed yet. I was more concerned about the driveshaft since the ujoint straps are just straps whereas the halfshafts on the BB have ujoint caps. Although, I haven't heard of the straps going, they just look too flimsy. I haven't figured out what to do with the parking brake cable since it would be in the way of the halfshaft loop which goes into the crossmember(loop is just rearward of the the ujoint after the trans output shaft).

I spoke with Steve at Drag Vette about this same concern. He said the DS U-joint, U-bolt straps were never found to be a problem with failure. There is way more stress on the half shaft u-joint, u-bolt straps, so the BB caps are recommended for HP applications. It is important to not overtighten the u-bolts in DS,or HS, as they can deform the cap and result in premature failure. Tighter is not always better. Factory torque specs should be followed, I believe it is 18 lb/ft.(refer to your manual)

Generally, unless your differential yokes were drilled and tapped for the screw in u-joint BB caps, u-bolt straps are used to hold the u-joint caps. I believe there are BB type caps available with studs, so you can get the same support as the BB caps with no threads in the yoke. I do not have any experience with them, just mentioning them as an item I remember seeing in a non Corvette specific catalog.

I believe he said the same thing to me, but I don't recall. I was ready to upgrade the driveshaft straps to girdles that Moroso sells. Change my mind after some said it wasn't neccessary. Here they are and they appear to be stronger than the stock straps.

http://www.jegs.com/i/Moroso/710/85820/10002/-1


http://www.jegs.com/i/JEGS+Performance+Products/555/60604/10002/-1

 

[Red]

Yup...they are what I was talking about. It was the Moroso girdles that I had seen in the same catalog and was talking about. I would favor the Jegs caps for the ARP fasteners with nyloc nuts, but the gold anodize favors my eye. If anyone is using these girdles, how about a report?

 

[Fuelie74]

I looked earlier this year, but couldn't find any cap girdles that would fit the smaller 1310 caps. Does anyone make them?