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  #641  
Old 07-20-2016, 02:12 PM
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It was over 3 years ago. The only reason I remember it is because I still had the parts and tools sitting in a drawer to remind me lol.
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  #642  
Old 07-20-2016, 04:47 PM
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Is your O2 Sensor flat and not slightly down hill as it sort of looks in the pixure?
O2's should be pointed down hill: Sensor low & Wires High.

E
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  #643  
Old 07-20-2016, 04:59 PM
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Thanks for catching that E. They should be slightly above horizontal as you said, but I think I rotated the exhaust on the v-band flange while I was bumbling around under there. They are only finger tight at the moment and I need to cinch them down.
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  #644  
Old 07-25-2016, 12:12 AM
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So I spent tonight checking out the existing driveshaft to see if it needs lengthening or what since the transmission is a bit forward of where it used to be. What I found was that at ride height the shaft has 1-3/8 in of travel left into the transmission and about 2" of spline engagement. When I let the suspension go to full droop (shock limited) I found the shaft actually went into the transmission about 1/8" further, increasing the spline engagement. Why I have no idea - all I can guess is the pinion must be rotating up to compensate for how far it moves down. What I gather from this is that my driveshaft does not need to be lengthened or shortened since it has more than the spline diameter of engagement and it's unlikely to move much in the range of suspension travel.

So that made me think perhaps I should measure pinion angle at ride height. Relative to the transmission, the pinion is pointed down 6.2 degrees. The drive shaft itself is 1.6 degrees relative to the transmission, giving a working angle of 1.6 degrees for the transmission u-joint and 7.8 degrees for the pinion u-joint. I have been reading up on pinion angle and it seems there's a lot of debate on how much you should have to compensate for how much the pinion will rotate up under load. In my case I have multi leaf springs with slide-a-links (similar to cal trac bars) and it's hard to say what it will do during normal street driving.

Anybody have some wisdom to share on this topic? I am not sure if this is too much angle or if it's an okay starting point. I'm not even sure what it was before I started this whole swap.

Edit I also measured the u-joints and they are 1310s. Hope they are up to the task.
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Last edited by TheBandit; 07-25-2016 at 12:58 AM.
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  #645  
Old 07-25-2016, 12:46 AM
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Here is a PDF of the ford body builders guide for driveshafts and axles;

http://www.therangerstation.com/foru...9&d=1389987591
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  #646  
Old 07-25-2016, 01:36 AM
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That's helpful except I don't see any info on compensating for pinion rotation under load.

Watch this pinion rotate up after it gets loaded up:
https://youtu.be/OtdgTdSx-nE
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  #647  
Old 07-25-2016, 08:23 AM
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IMO, there's no real magic in pinion angle. Some people attribute big handling changes to it, and I don't see that happening unless the mechanism used to adjust pinion angle is what's causing the difference.

If the bars are truly effective at preventing the axle from wrapping up, I would think you could take some of that pinion angle out. The most efficient torque transfer is going to happen when the pinion and the transmission output shaft are parallel and the U-joint angles are minimized. But, this is the dynamic scenario when everything is under load, the suspension has squatted, and whatever axle wrap that is going to occur has happened.

So that's the big question: how much does the pinion angle change under load? Once you have an idea of what that might be, then you can make a decision on how far to adjust the static pinion angle to compensate for that change.
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  #648  
Old 07-25-2016, 01:38 PM
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It makes sense that the pinion angle would have very little effect on the overall performance of the car while I would expect significant effect on vibration and stresses on the driveline. I want the joints to operate at roughly the same angle under "load", but I have no idea how much pinion movement I will actually have. I'm having a hard time even finding a rule of thumb that's suitably supported. It does seem like, given the ranges I've seen, that the ~6 degrees I'm measuring is probably not going to blow anything up, so I suppose I will start with that and see what happens.
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  #649  
Old 07-25-2016, 03:06 PM
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I think you're right about that, ~6 degrees is well within the operating range of any normal U-joint.

I'm trying to think of a low-tech way to measure how the pinion angle changes in the car, so you can check once it's running and adjust accordingly. GoPro and an inclinometer won't get it because it relies on gravity for zero.
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  #650  
Old 07-25-2016, 03:15 PM
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clamp a bar to the axle going forward along side the drive shaft.
Mount a grease pencil at the front end. Mount a piece of cardboard or metal that the grease pencil can mark on.
Dump the clutch and look at the marks. :)

Under cruise conditions you want the angles of the u joints to be the same on each end, ie the pinion shaft should be parallel to the output shaft on the trans. The don't have to be in line just parallel.
U joints speed up and slow down when working at an angle If the angles don't cancel out that effect you will get vibrations.
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  #651  
Old 07-25-2016, 03:40 PM
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Thanks for the input and ideas. Using a pencil is an interesting idea, but that would also be affected by the up/down movement of the suspension. I might be able to measure angles from camera images, but there may be some error involved.

I gave video analysis a shot on this youtube video, overlaying lines of known angle until they looked like a match using Microsoft Visio. It seems the pinion rotated up about 7degrees under load. I did not see a significant change in the driveshaft angle, perhaps because it also looks like the suspension rebounded (judging by the wheel relative to the body), but it's hard to tell due to the fisheye of the lense.



This is an interesting point of reference, but I have no info on the car other than what I can see in the video.
Attached Images
File Type: jpg pinion angle.jpg (48.2 KB, 449 views)
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  #652  
Old 07-25-2016, 04:45 PM
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Not being a Rocket Sturgen I offer the following with salt.

On this car I would set the pinion centerline 1.5° below parallel with the centerline of the output shaft of the transmission, at ride height.
My reason is based on the fact that the pinion centerline will rotate under torque and that rotation will let the pinion climb up into roughly parallel where you want it to run under torque. My number is empirical.

If you are really curious about what will actually happen you could set the car on blocks under the wheels (only to get access) and set the brake.
Then put a piece of pipe through the U-joint yoke and feed a known amount of force into the known length of pipe.
It would then be a simple matter to record the change in the pinion angle.
No, this will not give you THE number because you will be be working a dynamic system as a static scenario and dynamically there are a million numbers.


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  #653  
Old 07-25-2016, 07:28 PM
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I like that! It would give you a good idea on how much it moves to guide decision making. Probably an 80% answer, anyway.
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  #654  
Old 07-26-2016, 10:02 AM
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E thanks for the input and the testing idea. Tom Woods suggests a similar study in his driveshaft 101, except using the engine to apply torque through the system while the parking brake is engaged.

I'll give that some thought - thanks!
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  #655  
Old 07-26-2016, 10:45 AM
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Quote:
Originally Posted by TheBandit View Post
E thanks for the input and the testing idea. Tom Woods suggests a similar study in his driveshaft 101, except using the engine to apply torque through the system while the parking brake is engaged.

I'll give that some thought - thanks!
I don't recommend that anyone be under a rig while doing this kind of test using the engine...
Ever for any Reason.
Kan't put enough emphasis on that!!!

E
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  #656  
Old 07-26-2016, 11:39 AM
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Ok, maybe I missed something since I haven't read the entire build thread(yet, I get easily distracted sometimes.....squirrel!). But if you want to set the car up to drag race then I would add ladder bars, if you want to autocross it then a linked rear would be the way to go, if both I'd seriously consider linking the rear. This allows you to tune the suspension to fit the flavor of the day. Did this get covered and I missed it? Yes it's more money and time but you are years into this and it seems you are being very thorough on the build. Carry on.
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  #657  
Old 07-26-2016, 03:07 PM
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Quote:
Originally Posted by entropy View Post
I don't recommend that anyone be under a rig while doing this kind of test using the engine...
Ever for any Reason.
Kan't put enough emphasis on that!!!

E
100% agree. I think the method I like the most is video analysis. I think I'm going to leave as is and see what I end up with on video while driving.

Regarding linking the rear, that is a long term possibility. I already have a traction device on my leaf springs (slide a links, similar to cal trac bars) for now.
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  #658  
Old 08-16-2016, 01:23 PM
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I'm happy to report the MSD 3304 terminals work on the MSD 8.5mm wiring. Here's a shot of the crimped coil terminal:



Half the plug wires are assembled and routed now.



I had a really hard time getting the plug wires through the long/straight boots at the plug wire end. I tried dielectric grease, which I've used successfully in the past, and it was almost impossible to get the wires through. I discovered dish soap worked worked a lot better - light coating inside the boot and outside of the wire made it go in like butter.

There is one issue with using the soap though; the boots will slide around so easily, you can't install the wires onto the coils right away or the terminal will slip down into the boot rather than snapping into the coil. I found it was better to assemble the boots and let them sit overnight for the soap to evaporate; after that the boots become impossible to slide around. Here is the coil side terminal at the right depth in the boot - basically flush with the end.



I have a bit of a problem with insufficient clearance for installing the wires onto the coils. There's just not much space behind my intake manifold so it's hard to grip and press in the wires. I ordered a set of 45 degree plug wire pliers that I'm hoping will make things easier.
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Last edited by TheBandit; 08-17-2016 at 11:22 AM.
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  #659  
Old 08-17-2016, 08:23 AM
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I like it! Nice and clean. Thanks for the tip on getting the wires into the boots.

I like the 45 degree boots on the coils. I take it MSD has a few options on boot styles to fit different applications.
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  #660  
Old 08-17-2016, 04:16 PM
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Thanks Graham! Relocating the coils was a lot of work (especially for the wiring), but I love the way these valve covers show!

Forgot to add I also picked up a few bits for the cold air intake and mocked up where the filter will go in the area where the battery used to be.









Parts include:
Spectre 97992 90deg 4" x 7" long and 9729 22deg 4" mendrel bends
Edelbrock 43690 black conical air filter (11.5" long 7" dia x 6.5" dia)
HPS SSTC-108-116 stainless t-bolt clamps
GM MAF pad, can't recall the P/N.

I need to add a couple of couplers. I'm thinking hump connector between the straight section of tube and the 22deg elbow, then fix the elbow and filter into a box and duct to cold air from under or through the radiator support. How and when I will build said box is up in the air.
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