pinion angle or driveline?
03-13-2009, 10:41 PM
#141
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Thread Starter
Join Date: Dec 2005
Location: Hills of California
Posts: 5,208
Im pretty persistent...but this little adventure is reaching the termination point.
When I told the guy at the shop the 6 deg shims caused a vibration he thought maybe the total angle on the DS was now too high. He suggested raising the trans to near -1 deg. I cant do that because the trans would hit the support in the tunnel just behind the shift housing.
Im not able to effectively rotate the pinion adding the shims does a better job of lowering the rear of the car than it does actually moving the pinion up...4 deg gets me .75 deg of angle change.
at this point im not sure what to do next
do you have any suggestion on how I might install the shim to make them more effectivly change the angle?
Thanks
-Gun
When I told the guy at the shop the 6 deg shims caused a vibration he thought maybe the total angle on the DS was now too high. He suggested raising the trans to near -1 deg. I cant do that because the trans would hit the support in the tunnel just behind the shift housing.
Im not able to effectively rotate the pinion adding the shims does a better job of lowering the rear of the car than it does actually moving the pinion up...4 deg gets me .75 deg of angle change.
at this point im not sure what to do next
do you have any suggestion on how I might install the shim to make them more effectivly change the angle?
Thanks
-Gun
03-13-2009, 11:58 PM
#143
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Thread Starter
Join Date: Dec 2005
Location: Hills of California
Posts: 5,208
Okay that's interesting that you get 1:1 results on your shims and I get very little change.
heres how I measured it:
1) put 4 foot level on roof of car with car on level pavement and took pic of level bubble and made sure I could place the level back on the roof of the car with repeatable results.
2) drove front of car on ramps
3) jacked car up by diff housing so it was still under the same load as when on the ground.
4) watched bubble level until it was at the same position as it was on the ground.
5) When to trans side of DS and turned DS until the U joint on the yoke (one with the nice flat surface) was straight up and down and then set top of Robart angle meter on that surface and took reading....Same process for Diff.
6) removed 6 deg shim repeated measuring process.
I know this isn't a 100% accurate but it is very repeatable so the error should always be nearly the same (I would say +- .25 deg) and that's what is important
I have a pretty new leaf spring setup in the back that sit 1" lower than stock and a 1" swaybar. What could be eating up the angle change so its not showing up on the pinion?
Ill get some pics here in the next week or so and show you guys what im working with.
-Gun
heres how I measured it:
1) put 4 foot level on roof of car with car on level pavement and took pic of level bubble and made sure I could place the level back on the roof of the car with repeatable results.
2) drove front of car on ramps
3) jacked car up by diff housing so it was still under the same load as when on the ground.
4) watched bubble level until it was at the same position as it was on the ground.
5) When to trans side of DS and turned DS until the U joint on the yoke (one with the nice flat surface) was straight up and down and then set top of Robart angle meter on that surface and took reading....Same process for Diff.
6) removed 6 deg shim repeated measuring process.
I know this isn't a 100% accurate but it is very repeatable so the error should always be nearly the same (I would say +- .25 deg) and that's what is important
I have a pretty new leaf spring setup in the back that sit 1" lower than stock and a 1" swaybar. What could be eating up the angle change so its not showing up on the pinion?
Ill get some pics here in the next week or so and show you guys what im working with.
-Gun
03-14-2009, 01:33 AM
#144
4th Gear Member
Join Date: Aug 2008
Location: Goodyear, AZ
Posts: 1,674
Gun, Kalli and Scott, you guys are killing me. I have been following this thread hoping to find the answer to my vibration problem. I have a vibration that starts at 50mph and gets progressivly worse. It is still there when i push in the clutch.
I have a question, which yolks are you using? I am using the yolk from my 66. not the one that came with the t5.
What cross members are you using. Did you purchase it or fab it yourselves. ( i made mine)
Now i am thinking that I have several issues. One is that there are worn parts inside my t5.
I also think that my t5 is sitting too low in the rear. i have not checked tha angle, but at the time did not know it was important. i just heald it up with a jack and measured for the cross member parts.
I did not shorten my shaft and it is tight. i think it may be contributing to the vibe
Shatty motor mounts. when i even accelerate a little there is a rotating of my trans, a lot. i hear a clunk and the shifter really mooves to the right.
I am going to start tackling this problem and i will solve it. Watch for my post. I will not be defeated.
I have a question, which yolks are you using? I am using the yolk from my 66. not the one that came with the t5.
What cross members are you using. Did you purchase it or fab it yourselves. ( i made mine)
Now i am thinking that I have several issues. One is that there are worn parts inside my t5.
I also think that my t5 is sitting too low in the rear. i have not checked tha angle, but at the time did not know it was important. i just heald it up with a jack and measured for the cross member parts.
I did not shorten my shaft and it is tight. i think it may be contributing to the vibe
Shatty motor mounts. when i even accelerate a little there is a rotating of my trans, a lot. i hear a clunk and the shifter really mooves to the right.
I am going to start tackling this problem and i will solve it. Watch for my post. I will not be defeated.
03-14-2009, 08:35 AM
#145
4th Gear Member
Join Date: Sep 2008
Location: Connecticut
Posts: 1,839
If you know the problem is that you tranny tailshaft is too low, and you don't want to cut the tunnel, you could use these Ron Morris adjustable motor mounts that lower the engine 1/2".
http://www.ronmorrisperformance.com/...y_Code=Hot_New
Only problem is I don't think you should throw money at it until you really know what the issue is. I will say that I am skeptical of bolt in T5/TKO solutions in a 65/66. Most do it by lowering the tranny mount introducing excessive angle that is then compounded by rear lowering springs. Kind of the opposite issue 4x4 truck owners have when they install lift kits without addressing the driveshaft angle. I lowered the engine in my 66 a 1/2" and then raised the tranny mount by about 3/4" from stock. I am running reverse eye 4 1/2 leaf springs and the rear should sit lower by about 1 1/2" over stock.
I'm hoping to start my engine for the first time this weekend and perhaps a quick trip around the block (it's not registered yet). I'll get a better idea of my driveline angles once I get it off the lift.
While I still think your driveshaft is too short, it does seem you have angle issues. I look forward to seeing your pictures as they may be more valuable than 1000 words.
Good luck man, I know this must be a big pain in the ***.
http://www.ronmorrisperformance.com/...y_Code=Hot_New
Only problem is I don't think you should throw money at it until you really know what the issue is. I will say that I am skeptical of bolt in T5/TKO solutions in a 65/66. Most do it by lowering the tranny mount introducing excessive angle that is then compounded by rear lowering springs. Kind of the opposite issue 4x4 truck owners have when they install lift kits without addressing the driveshaft angle. I lowered the engine in my 66 a 1/2" and then raised the tranny mount by about 3/4" from stock. I am running reverse eye 4 1/2 leaf springs and the rear should sit lower by about 1 1/2" over stock.
I'm hoping to start my engine for the first time this weekend and perhaps a quick trip around the block (it's not registered yet). I'll get a better idea of my driveline angles once I get it off the lift.
While I still think your driveshaft is too short, it does seem you have angle issues. I look forward to seeing your pictures as they may be more valuable than 1000 words.
Good luck man, I know this must be a big pain in the ***.
03-14-2009, 10:46 AM
#146
6th Gear Member
Join Date: Oct 2006
Location: Cork, Ireland
Posts: 6,417
that's good to know with the mounts. i haven't got around shimming yet as i'm busy with other projects allthough I have the partws already.
my setup:
vibrates from 50 on but gets less at 60. sweet spot is around 55
9" rear axle 1310 yoke
new T5 yoke
driveshaft not cut, got it off a 1966 automatic
original 66 bellhousing with adapter plate (not t5 bellhousing).
but for the moment my angles are off anyway, so I'll have to check shimming first. but my trans is pointing down as well. a good bit
my setup:
vibrates from 50 on but gets less at 60. sweet spot is around 55
9" rear axle 1310 yoke
new T5 yoke
driveshaft not cut, got it off a 1966 automatic
original 66 bellhousing with adapter plate (not t5 bellhousing).
but for the moment my angles are off anyway, so I'll have to check shimming first. but my trans is pointing down as well. a good bit
03-14-2009, 06:49 PM
#150
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Thread Starter
Join Date: Dec 2005
Location: Hills of California
Posts: 5,208
shifter looks centered!
the next step is to observe pinion angle and shim placement and try to figure out why the pinion appears to not be changing angle when shims are added....It could be lots of things....At least i have a problem to chase now
-Gun
P.S going back to the 2 deg shims made a really big improvement but didn't fix the problem.
the next step is to observe pinion angle and shim placement and try to figure out why the pinion appears to not be changing angle when shims are added....It could be lots of things....At least i have a problem to chase now
-Gun
P.S going back to the 2 deg shims made a really big improvement but didn't fix the problem.