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DeepSea117
10-06-2005, 03:49 PM
Hey all,

I was doing some field testing of my Marauder at above-average speeds, and I notice when clicking off the overdrive and flooring it caused a slight increase in vibration, which I assume is why everyone is swapping out the stock driveshafts. Any reason why the vibration would go away with overdrive on?
Smokie
10-06-2005, 04:25 PM
Hey all,

I was doing some field testing of my Marauder at above-average speeds, and I notice when clicking off the overdrive and flooring it caused a slight increase in vibration, which I assume is why everyone is swapping out the stock driveshafts. Any reason why the vibration would go away with overdrive on?
Lower Rpm's, do you have stock gears?
ctrcbob
10-06-2005, 04:40 PM
Don't matter if you are in 3rd or 4th. Driveshaft spins the same RPM.
Smokie
10-06-2005, 04:44 PM
Don't matter if you are in 3rd or 4th. Driveshaft spins the same RPM.You believe that at 100 miles an hour in 3rd gear your driveshaft is turning the same rpms as 100 miles an hour in 4th gear?
bugsys03
10-06-2005, 05:19 PM
You believe that at 100 miles an hour in 3rd gear your driveshaft is turning the same rpms as 100 miles an hour in 4th gear?
I believe that
Bradley G
10-06-2005, 05:26 PM
Me too! .............Too Short:mad: :D
thePunisher
10-06-2005, 05:39 PM
yessir your wheels are moving at the same speed whetner youre in 3rd or 4th....driveshaft speed doenst change unless vehicle speed changes.....
ctrcbob
10-06-2005, 05:40 PM
Yep. Driveshaft is connected from the output of the transmission to the rear end. At 100mph, the rear end, and the driveshaft don't care what gear you are in. At any given speed, it spins the same speed no matter what gear the transmission is in. The faster the car goes, the faster the driveshaft spins.
Everyone should know that.
ctrcbob
10-06-2005, 05:41 PM
Punisher,

Thank you. Like I said, everyone should know that.
Smokie
10-06-2005, 05:54 PM
..... Like I said, everyone should know that.That's what I get for thinking.:lol: Is time for me to go to the corner....:corner: ......would you believe???? driveshaft goes faster at any given speed with......taller gears?????
cyclone03
10-06-2005, 06:10 PM
That's what I get for thinking.:lol: Is time for me to go to the corner....:corner: ......would you believe???? driveshaft goes faster at any given speed with......taller gears?????



Ok here goes.....

Drive shaft spins SLOWER with Taller gears and faster with lower gears.


ie: 3.55:1's are TALLER than 4.10:1's.
3.55=tall 4.10 = low 5.14 = way low 2.23= way tall.
Bradley G
10-06-2005, 06:13 PM
You and Smokie studied together:P
Ok here goes.....

Drive shaft spins SLOWER with Taller gears and faster with lower gears.


ie: 3.55:1's are TALLER than 4.10:1's.
3.55=tall 4.10 = low 5.14 = way low 2.23= way tall.
Hotrauder
10-06-2005, 06:15 PM
Huh??? No wonder this corner is getting crowded..I must have been and still am confused. That Dam Imported Beer, again.:beer:
Smokie
10-06-2005, 06:22 PM
Have we got everybody totally confused yet.....:confused: :rofl:
Bradley G
10-06-2005, 06:22 PM
Tall as in Higher # 4.10 >3.55The drive shaft turns further: 4.1 times per one axle revolution VS. 3.55 revolutions to rotate the axle one revolution.
Smokie
10-06-2005, 06:27 PM
Tall as in Higher # 4.10 >3.55The drive shaft turns further: 4.1 times per one axle revolution VS. 3.55 revolutions to rotate the axle one revolution.Thank God somebody knows how to add...I must have skipped school that day......:grad:
GreekGod
10-06-2005, 07:57 PM
One possible exception comes to mind....as in slicks on a AA Fueler... they grow in diameter as speed increases, so...if a MM had tires that 'grew' in diameter, the over-all drive ratio would change and the driveshaft speed would vary with speed. This is similar to the action of a CVT (constant variable transmission). I only mention this because technically tire growth is a factor to be considered and an important calculation for land speed record attempts at Bonneville. It would be interesting to see Lidios car run at Bonneville!
DeepSea117
10-07-2005, 01:01 AM
Running stock 3.55...and it's under acceleration. Just seems to me I hear more vibration with O/D off, but during WOT in the higher RPM's. Lower RPM's are fine, but get high enough and I turn the O/D back on just to lower the RPM's
ctrcbob
10-07-2005, 04:20 PM
Hey Guys, DEEPSEA is talking about OD. That is Transmission, and in talking about transmission, the driveshaft and rearend don't care what gear the transmission is in, 3rd or 4th (OD). The rotation is the same as long as the car speed stays the same.

Some of you have turned it around and started to talk about Rear End Gears. True with the different gears in the rear end, the driveshaft will turn faster with 4.11's than with 3.55's with car going at same speed. (However how many of you have a two speed rear end as that would cause the drive shaft to spin at different speeds).
Smokie
10-07-2005, 04:33 PM
Running stock 3.55...and it's under acceleration. Just seems to me I hear more vibration with O/D off, but during WOT in the higher RPM's. Lower RPM's are fine, but get high enough and I turn the O/D back on just to lower the RPM'sYou hear or feel ??? Acceleration in the mid-range or near redline??? Having some idea what area you hear or feel the vibration would help. It could be a vibration coming from a catalytic converter.
DeepSea117
10-07-2005, 07:00 PM
You hear or feel ??? Acceleration in the mid-range or near redline??? Having some idea what area you hear or feel the vibration would help. It could be a vibration coming from a catalytic converter.
I feel and hear the vibration, and it happens during WOT around 4000 or so on up to redline, in 4th gear. It's definitely between the driver and passenger side seats. At that point I turn O/D back on. It may also happen at 4000 up in O/D at WOT, but at that point I figure I'd be hitting the speed limiter :)