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I fiqure if I could get the crankshaft centerline at 0* and leave the pinion at 3* down that should be good. But getting the crankshaft center line at 0* is appearing to be easier said than done.

How many degrees should I strive to keep my crankshaft around? Or are you just saying that in referance to finding my true driveline operating angle? I understand using the ground is not the best way, but I am using it as my common referance point, as you stated for mocking-up.

PS. I might have to go back and change somethings once the cage is in and the car is at final weight.
 

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jones said:
Or are you just saying that in referance to finding my true driveline operating angle?
Yes, exactly.

While all the individual component driveline angle measurements might be referenced off the ground, that's all they are.......reference points. You factor these individual reference points (angles) against each other to find the actual operating angles (or interference angles) of the front & back U-joints to keep the U-joints "happy" under loading.

In my opinion over the years most of the confusion people have had with this is probably from it being called "pinion angle" or "setting pinion angle" which makes it sound like your ONLY concerned with the pinion it's self.

I have known people in the past that have claimed that pinion angle is ONLY to be in reference to the ground at some magical "one-size-fits-all" number. But when you question their theory on this and ask what happens if their magical "off the ground" number is used on many different cars that have many different driveshaft angles, their theory goes to **** and you can end up with some dangerous binding depending on the car type.
 
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Jones..

My engine is 2 degrees down as measured off the balancer. I used a Ford Truck tranny mount in the rear.. It's quite tall. If you need pic's of the mount PM me and I'll send them to you..

Trying to help.. by the way I was off on pinion angle. I fixed it and help pick up the 60 foot some.

Laters!

Les

 

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D.I.L.L.I.G.A.S. said:
jones said:
Or are you just saying that in referance to finding my true driveline operating angle?
Yes, exactly.

While all the individual component driveline angle measurements might be referenced off the ground, that's all they are.......reference points. You factor these individual reference points (angles) against each other to find the actual operating angles (or interference angles) of the front & back U-joints to keep the U-joints "happy" under loading.

In my opinion over the years most of the confusion people have had with this is probably from it being called "pinion angle" or "setting pinion angle" which makes it sound like your ONLY concerned with the pinion it's self.

I have known people in the past that have claimed that pinion angle is ONLY to be in reference to the ground at some magical "one-size-fits-all" number. But when you question their theory on this and ask what happens if their magical "off the ground" number is used on many different cars that have many different driveshaft angles, their theory goes to **** and you can end up with some dangerous binding depending on the car type.
See, I was trying to explain what we have been talking about to another person. He was telling me that one of the major Mustang suspension dealers told him to just base his pinion angle 3* down from level. Now that's not to say that the guy wasn't sharing a whole lot of other information, but that is all that he told his customer.

I agree with you though and totaly makes sence. I'm just trying to stuff a 10lb cat in a 5lb bag. If I was using a c4 instead of a c6 it would be a beeze.
 

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s_stang said:
Jones..

My engine is 2 degrees down as measured off the balancer. I used a Ford Truck tranny mount in the rear.. It's quite tall. If you need pic's of the mount PM me and I'll send them to you..

Trying to help.. by the way I was off on pinion angle. I fixed it and help pick up the 60 foot some.

Laters!

Les

Are you saying that the 2* is a problem? Is your 2* down in the rear? Are you running a C6?
 

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jones said:
I was trying to explain what we have been talking about to another person. He was telling me that one of the major Mustang suspension dealers told him to just base his pinion angle 3* down from level.
In the guy's defense (that your talking to) who's to say that his number referenced off the ground might just happen to work perfect for the type car/combo he is working with.

As an example, lets say his car is sitting there ready to race, (sitting on the ground at ride height, at full race weight, & driver sitting in the car) and using "his" pinion angle/number of -3.0* that is only referenced off the ground. There are indeed some engine centerline angles that would probably work to give a usable 4-link/ladder bar operating angle at the rear U-joint in the -1.0*, -1.5*, or -2.0* range.

In this example if you use his "off the ground" pinion number of -3.0* , while at the same time pointing all the engine/trans/driveshaft centerlines in a straight line (the "drag use only" method) at the pinion with the crank nose pointed "nose-down" at 1.0* The end result would be a pinion-to-driveshaft operating angle of -2.0*. Then changing the crank nose from 1.0* to 1.5* "nose down" would change the rear operating angle from -2.0* to -1.5* operating angle (and so on, and so on, etc, etc).

Obviously his "off the ground number" of -3.0* wouldn't be the best choice in a 4-link/ladder bar car that had the engine/trans/driveshaft centerlines pointing at the pinion at a "crank nose-up" angle of say 2.0*. That would result in an excessive (for drag racing) rear U-joint operating angle of -5.0*

It's all in how you look at the problem in three dimensional space. Crazy as it may sound, if for some strange reason you wanted to mock up all the driveline angles while the car was sitting "up-side-down" on jack stands it could be done as long as you set all the axle-to-frame ride hight measurements correctly. Sure all the up-side-down driveline angles would look damn strange when referenced off the ground, but the resulting U-joint operating angles would still be correct in relation to each other.
 

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I agree, but it sure doesn't help when you are trying to explain it to the guy! :lol:



I hope to get something accomplished this weekend!
 

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I know the engine and transmission setup will clear everything with the carb pad level. So I think I will just go that route.
I believe the carb pad is -4* to the crankshaft centerline
 

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I ended up going with 3*. Everything just seemed to clear and workout smoother for me. The engine sits level from right to left and is dead centered with the pinion center line.

I'll have more pictures in my turbo mustang build thread.

 

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Now isnt this also true? If you did lower the nose of the engine to 0.0 (level) you also would have to lower the trans mount because in a fox body car doesnt the trans output shaft sit higher than the pinion. If not you would end up with 2 angles on the driveshaft (U-joint) but opposite from each other. So a nose up and a straight line to the pinion with your 2 angles only at that point seem to me would work better.
 

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nitro717 said:
Now isnt this also true? If you did lower the nose of the engine to 0.0 (level) you also would have to lower the trans mount because in a fox body car doesnt the trans output shaft sit higher than the pinion. If not you would end up with 2 angles on the driveshaft (U-joint) but opposite from each other. So a nose up and a straight line to the pinion with your 2 angles only at that point seem to me would work better.
That would be true if there wasn't a steering rack in the way. You have to raise the tail shaft in order to get it to 0*. That's where I hit the transmission tunnel. I could have installed offset rack bushings but they are only good for 3/8 to 1/2" and screw with your bumpsteer even further.

Yes you would seem to have less driveline angle the more nose high you can get. Also, the further back the engine sits the more driveline angle you have.
 
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