Well, chalk this up as a learning experience. Side exit exhaust dont do it!

No doubt about it, a 1-piece shaft will be more likely to vibrate. IMO, replacing your stock 2-piece drive shaft with an aftermarket 1-piece unit is a dubious move at best. I could understand if the stock shaft was a known weak link in the driveline or if you were raising your engine’s power output to a level that exceeded the stock shaft’s capability but even then, I’d personally be looking for a heavier duty 2-piece solution. A good rule of thumb is that the longer the shaft, the weaker the shaft, and the more likely it is to vibrate.
I’d suggest that if you’re dying to upgrade your drive shaft, switch to the Demon shaft.

 

I have a DSS 9 inch conversion on my car. A 1 pc is the only option. I started driving cars when one piece drive shafts were 6 ft long and they didn't vibrate then. This one shouldn't vibrate now, that is the reason for the CV joint at the tranny end. The vibration has gotten worse since I picked the car up two years ago. 2 years ago it was barely noticeable in fact most people wouldn't even notice it. After doing the work to the car last summer to repair the rear inner cv joints, the car didn't vibrate much more than normal and then this spring I took it out of the garage and for some reason now it's vibrating and I did nothing to it. I am suspicious that the drive shaft is bent. I talked to my dad about the drive shaft being 0.005 out of round (he was a mechanic his whole career). He said that that is enough to cause a vibration.

 

I put Loc-Tite on them first thing when I got the car home last year.

 

How would the shaft get bent while sitting in the garage?

 

That's what has me

 

A long shaft can bend from it's own weight.....that's why the shafts on navy ships (especially aircraft carriers) are rotated slowly each night for a given amount of time to ensure the shaft does no sit in the same position for long periods of time. And by slowly, I mean it takes 7 min to rotate 1 1/4 turns.......

Now, having said that, I would not expect it to be a real issue on a car or truck driveshaft, as the length & weight aren't significant.

 

I have put the driveshaft and exhaust back on the car and taken it out for a drive. That vibration is gone. It was the difference in weight of the six bolts attaching the CV joint at the front of the driveshaft to the output flange of the tranny. Four out of the six weighed very close to each other but then there were these two oddballs that were five grams each underweight. I replaced all six bolts with brand new bolts and before I install them I match weighted them to each other.

 

The vibe is fixed but now on to other issues. The tune mainly. UGH!!! My 8 yo i1000 DCX has always been glitchy and after an update last week will not log AFR now through the analog input. So I bought the i3 Platinum InTune to replace the pile of junk. Should be here Monday. Also having troubles with belt slip on the ProCharger. I only have the 6 rib setup and about 55% wrap on the SC pulley. I am going to make an additional idler pulley to force the wrap to about 70-80%. Will post pics when done.

 

The car has been running fantastic. Still have some fine tuning to do and the roll cage, new seats, back seat elimination kit, new subs with relocated amps, new fuel rails, the new tires, custom made lift pump in fuel tank, and gauge pod all need installed. Garage Bar has to be built first. Will finish the car after Aug 21st.