NHRA approved driveshaft loop ?

I have the same one in Dave's picture as well. I think they were from Siska originally no?

Anyway, mine bolted right in. No muss no fuss and I have a pretty big exhaust as well.

Ira
 
We made this one up for my XR7.

safetyloop2.jpg

safetyloop1.jpg

safetyloop4.jpg


The top loop goes up as two halves, to allow you to install it without removing the exhaust or driveshaft. The top plate bolts those two halves together. Access to those two top bolts is provided by removing the shifter and working through the factory shifter opening. The bottom of the loop is kicked up to clear the exhaust. The exhaust pipes are 3" at that location, and are tucked up into the tunnel pretty tightly.
 
I made one from a 1" long piece of 6" pipe and some 1"x1/8" stock. Couple hours and about 10 bucks.

that is NOT NHRA legal. here is what it says.......

In place of a crossmember, in the vicinity of the front universal joint, all cars in competition using open driveshafts, must have a retainer loop 360-degrees of enclosure, 1/4-inch (6.35 mm) minimum thickness and 2-inches (5.1 cm) wide, or 7/8-inch (22.2 mm) x .065-inch (1.65 mm) welded steel tubing, securely mounted and located within 6-inches (15.2 cm) of the front universal joint for support of the driveshaft in event of U-joint failure



notice the red piece of driveshaft in the lower left side of the picture...

Nesbitt1.jpg


http://www.competitionplus.com/inde...to-nesbitt-car-i-had-no-idea-what-htranspired

this right here is why i believe NHRA should make EVERYONE have 2 loops, one front one in the rear, and anything faster then 8.99's should have the tunnel. I was at the start line when Barb made this pass. this car is a brand new 120k chassis, was just finished in time for the nmra/nmca joliet race last month. there was nothing that showed that she was in trouble, even through everything, she kept that car right down the middle of the track.
 
Here is a couple pics of mine. I have also left the stock ones in place as well. Should the driveshaft fall it should have something to hold it all the way back. I may put another Summit loop at the back once I get the 3" exhaust back up in place and see how everything fits.
 

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So I take it by looking at the pics that you have to drill through your floor board to attach the loop. Is that all there is to the installation?

Dave, if you have another left I'll take it.
 
I can't believe this one..

Maybe it is because I have broken a few drive shafts in my day but to go cheap on this is just crazy.
I have twisted off a shaft and it has cost me a transmission once, another time the rear end and some of the floor pan. This is something that is a must on any car that is pushed hard.
The best thing is to put two of them on the car, one in front of the rear end the other just behind the transmission. I think the rules want them within one foot of the end. Some of you guys should have three of them to be safe. The thrid one placed in the middle of the shaft, just in case you twist it off like I did once.
You can get them for as little as $20 on sale and you can spend a lot more if you go for the complete drive shaft safty harness that are out there. Expect to spend somewhere around $450 for that setup.
Read the story that Keith posted and you will look at this in another light. Think safty please on this one... That's all I got to say on this.....Rich
 
Keith: Thanks for the info and the sanity check....I definitely be making an upgrade.


that is NOT NHRA legal. here is what it says.......

In place of a crossmember, in the vicinity of the front universal joint, all cars in competition using open driveshafts, must have a retainer loop 360-degrees of enclosure, 1/4-inch (6.35 mm) minimum thickness and 2-inches (5.1 cm) wide, or 7/8-inch (22.2 mm) x .065-inch (1.65 mm) welded steel tubing, securely mounted and located within 6-inches (15.2 cm) of the front universal joint for support of the driveshaft in event of U-joint failure



notice the red piece of driveshaft in the lower left side of the picture...

Nesbitt1.jpg


http://www.competitionplus.com/inde...to-nesbitt-car-i-had-no-idea-what-htranspired

this right here is why i believe NHRA should make EVERYONE have 2 loops, one front one in the rear, and anything faster then 8.99's should have the tunnel. I was at the start line when Barb made this pass. this car is a brand new 120k chassis, was just finished in time for the nmra/nmca joliet race last month. there was nothing that showed that she was in trouble, even through everything, she kept that car right down the middle of the track.
 
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I just finished putting one in today. It took a little bit of smoothing out with a flap disc on an angle grinder and I had to put a little more bend in a few spots, but for how cheap it was, it worked out well.

$20 from Jegs.

bba97275.jpg

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278d1402.jpg
 
that's a lot of nuts and bolts. I don't see any nyloc nuts either. Did you throw some loctite on those threads? Otherwise you may want to check them after the season to make sure none of them loosen up.
 
The kit came with nuts, bolts, and lock washers. It has four pairs of holes, on each L-bracket to select which loop height you need.
 
They're not as effective as nylon lock nuts are, but they certainly aren't zero. The spring like activity will serve as an added restraint as opposed to having nothing there. If it was only a washer with a crack in it, then that assumes there isn't any elastic memory in the washer itself. In the very least, it slows the rate at which the mechanical vibrations loosens the nut.

Anyways, I'll just keep an eye on it, regardless.
 
Check out this video showing a standard nut turning off a bolt when under vibration. then the next one showing a standard nut with a spring (split) washer.
http://www.boltscience.com/pages/junkertestplainnut.htm
http://www.boltscience.com/pages/junkertesthelicalspringwasher.htm

I'm not sure I would be confident in saying a lock washer is better than nothing. In fact, information at the site above states:

http://www.boltscience.com/pages/vibloose.htm
As a result, a rationalisation of the variety of locking devices used by such major companies has occurred. For example, conventional spring lock washers are no longer specified, because it has been shown that they actually aid self loosening rather than prevent it.

I'm not arguing that you shouldn't use them. Just trying to share some information I've dug up over the last couple years that I've found makes use of lock washers questionable. I've still used them in various applications, often times just from the idea of peace of mind, even though info I've seen says that is the opposite of what they give you.
 
It's cool, Mike. I looked at it as a conversation.

That's interesting stuff. Are the vibrations of the same magnitude in each test? I'm also a skeptic towards the split washers, but I have never assumed their effectiveness to be null. Thinking about it actually makes me agree with accelerating loosening of the nut or bolt. I give thought to many petty things, but not locking fasteners. Obviously nylocs aren't skeptical, once they're away from heat, at least.

They're annoying to tighten, though.:)
 
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yes, vibrations the same for each test. The company has something they call a junker which is a machine that is able to create shearing forces to duplicate vibrations over time but within a much shorter period. they've tested a number of fasteners and locking devices.

Their double nut test was pretty interesting as well.
http://www.boltscience.com/pages/twonuts.htm
 
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