Truck going on dyno, should I fear for my driveshaft?
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Originally Posted by Stoichiometric
After seeing 1slowhoe's mishap on the dyno, I am a little nervous about running 6000+RPM in 3rd gear. I am going to build loops for my truck, but I don't want to rush them and I want to get on the dyno Friday. I have a 2500HD so the driveshaft is steel and U-joints are bigger. Should I worry?
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Originally Posted by Stoichiometric
I put in 4" @ 72"
The 2 piece will suck up alot of any issues (along with some HP, unless you are like grippy and are making so much it won't be missed )
1slowhoe, that critical speed you spec is nice, but again, enter your specs into the calculator and make sure the length says 72". Watch how fast the critical speed drops. Pass 60" and it's another ball game.
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Originally Posted by dewmanshu
1slowhoe, that critical speed you spec is nice, but again, enter your specs into the calculator and make sure the length says 72". Watch how fast the critical speed drops. Pass 60" and it's another ball game.
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Originally Posted by dewmanshu
1slowhoe, that critical speed you spec is nice, but again, enter your specs into the calculator and make sure the length says 72". Watch how fast the critical speed drops. Pass 60" and it's another ball game.
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Originally Posted by agreif
I think his post above said ~54" right. So you had a "short" AL go? I had only seen (and experienced) the 72" AL's making a nice sin wave.
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My shaft is one piece (4x4 truck). It is 66" from u-joint to u-joint and about 61 1/2" from weld to weld. 3 1/2" dia. For the critical speed calc, does it consider the yoke length or tube length only?
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yoke center to yoke center.
I think that calculator only does takes aluminum into consideration. One of the driveshaft companies and tell them your contemplating a new shaft but would like to know how to figure out your current driveshaft's critical speed. If they can help you, GREAT, you have a good answer and you'll know they know what they are doing.
I think that calculator only does takes aluminum into consideration. One of the driveshaft companies and tell them your contemplating a new shaft but would like to know how to figure out your current driveshaft's critical speed. If they can help you, GREAT, you have a good answer and you'll know they know what they are doing.
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I'll call around tomorrow. I would feel much better to have the loops on before I dyno. I may wait or dyno in 2nd if I have a chance. How much difference is there between 2nd and third for comparison? If I dyno in 2nd now, then mod some more and dyno in third am I comparing apples to oranges? My critical speed is 5303 rpm, I can get the HP and TQ to meet then guess at the rest.
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Originally Posted by 1SlowHoe
It was my 54" (give or take) steel shaft that gave out. The aluminum better not give out. I paid $600 for that damn thing.