one piece drive shaft balancing

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kiwimanz
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one piece drive shaft balancing

Post by kiwimanz » Tue Jan 01, 2019 11:05 am

Hi all,
I have installed a baby T5 in my build and have gone with a one piece drive shaft. The drive shaft was built by Drive line Services here in Portland, very reputable shop so I know its good to go. I think my issue is insuring each end of the dive shaft is parallel to one another.
It looks the diff actually points uphill to accommodate the stock two piece, so to offset this I have shimmed down the cross brace to drop the end of the gear box. See video.
https://www.youtube.com/watch?v=gmV4qwLfOMY

I have been running the car up the road and doing mapping but getting heavy vibration from the drive shaft as the speed rises. Anyone have an idea how to sort this out?
Cheers
Linz

twin turbo
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Re: one piece drive shaft balancing

Post by twin turbo » Wed Jan 02, 2019 8:26 pm

IT need to be "straight" line from out of gearbox to difflange.

Lift the box back up? The diff is fairly straight since the 2 piece is also "straight" original.

But if allot of vibrstion, IT might be the prop itself...

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whitelx
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Re: one piece drive shaft balancing

Post by whitelx » Thu Jan 03, 2019 7:36 pm

Are you using one of the driveshaft adapters on the diff? You want the angles between the diff and trans to be within 3 degrees of each other. I have about 1.5 degrees. The diff isn't really adjustable, so it's a matter of shimming the trans mount or the engine mounts. I ended up pulling my shims out of the trans mount and shimming the engine mounts to get the angles better. I have very little vibration now and the mount I do have I attribute to a work tailshaft bushing. It's an old junkyard trans that makes a ton of noise and there's a lot of movement at the yoke, it's worn out.

I bought one of the magnetic digital angle finders off amazon. I had tried using an analog gauge and wasn't having much luck.Same with my phone, it just wasn't repeatable. The digital angle finder made it quick and easy.
Last edited by whitelx on Thu Jan 03, 2019 7:38 pm, edited 1 time in total.
1986 XR4Ti - 294rwhp/315ft-lbs
1992 Mustang 5.0 notch - 434rwhp/445ft-lbs
http://www.youtube.com/user/whitelx

my8950
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Re: one piece drive shaft balancing

Post by my8950 » Thu Jan 03, 2019 7:38 pm

What's a baby T5?

kiwimanz
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Re: one piece drive shaft balancing

Post by kiwimanz » Sun Jan 06, 2019 2:02 am

Thanks guys,
I put a 3' straight edge across the diff flange and measured from the ends to the center of the output shaft on the gear box. It was about a 1mm out of square over the distance to me was pretty darn good. I measures the vertical angle of the diff flange and the gear box output shaft and it was too far out so I have shimmed up the back of the gearbox and I'm about .2 deg out of parallel so I think that should be fine. Just need to run it now
Will report back
Cheers
Linz

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DPDISXR4Ti
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Re: one piece drive shaft balancing

Post by DPDISXR4Ti » Sun Jan 06, 2019 10:14 pm

First, as a general statement, getting a vibration-free car with a one-piece driveshaft and the Lima 2.3 is always a challenge with this car. I've had better luck with the 8.8 rear-end, but that could be attributable to several things. As mentioned above, I also had best results by shimming the engine up. Also, make sure your spacers on the transmission x-member are unequal (one side spaced down more than the other).

At the end of the day, I stopped measuring angles and just played around until I came up with a combo that was relatively vibration free.
Brad

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whitelx
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Re: one piece drive shaft balancing

Post by whitelx » Mon Jan 07, 2019 12:38 pm

I had asked about the driveshaft adapter earlier and didn't see a response about it. It may seem trivial, but it's an important question.

I purchased an adapter and had bad vibrations when I installed the 1-piece mustang driveshaft. This was after I had made sure the angles were good. i took the driveshaft out and had the balance checked on it. I made sure they checked before doing any work. The driveshaft was perfect. Then I took the adapter to them. Turns out with everything bolted together as an assembly, the driveshaft was now out of balance. The adapter was not balanced after production. I had the driveshaft and adapter balanced as an assembly (and marked for orientation) and now no more vibrations.
1986 XR4Ti - 294rwhp/315ft-lbs
1992 Mustang 5.0 notch - 434rwhp/445ft-lbs
http://www.youtube.com/user/whitelx

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