My 427 SOHC Build..... Finally the time has come!

[rcodecj]

As I do not have access to a 4 post lift at this time, I will certainly try and locate someone (or try something) to get the rear wheels resting on a solid surface and remeasure.  Hopefully it will still measure the same and I can take it out for a spin.

I'm almost hesitant to recommend this as perhaps you've thought of these ideas but....buy or steal some rough wood, the bigger the better, nail same togehter and place same under all 4 wheels. Better, get 4 steel milk crates and use them instead. Get two of those steel drive-up ramps but with removable ramps. I'm usually hesitant to drive a car up them but they can be used after jacking the car up with your floor jack and just use the horizontal part under the tires.

Heck, even these work well and cheap too: https://www.homedepot.com/p/8-in-x-8-in-x-16-in-Concrete-Block-100825/202323962

I've had to do the same or even build wood ramps to get under really low cars that even a std. floor jack was hard to get under the car. That and getting the car level but up in the air to more easily set toe, caster and check Ackermann angles.

No way on the concrete blocks. I've seen them explode after putting a cars weight on them.

Edit to say concrete blocks hold up houses but they are mounted flat side to the side not like a car with flat side to the top. Maybe that's the difference? I'd like to hear other peoples thoughts on this.

[cjshaker]

Concrete blocks wouldn't be a problem IF you use them flat sides out, like they're intended to be used, AND you use a section of 2x8 or 2x10 on the tops and bottoms. The wood keeps from forming hard pressure points that can fracture the blocks. It might not be OSHA approved, but it'll work fine. They can hold a lot of weight when used with some common sense. Getting the car jacked up high enough to get the blocks and 2 2x boards under each wheel might be a tougher matter.

DO NOT use them with the flat sides to the top/bottom!

[cobracammer]

May try that....  but of course a few 12 ton jack stands under the car (not in contact).  If the blocks give way, I would rather it fall an inch or 2 onto jack stands rather than a foot or 2 me   

[cobracammer]

Ok, got it up and on cement blocks.  Wood under the block and on top.  Jack stands for safety.

Best I could do was 0.5 for the rear end pinion.

Trans is still 2.8

Driveshaft ended up being 3.4?

With 2 degrees under power, that will put the rear end at 2.5 pointing at trans
And trans pointing at rear at 2.8

Couldnt get any closer.  Will this be ok?

Thanks again

[jayb]

Sounds close enough to me - Jay

[cobracammer]

Thanks! Took it out this weekend and I just wanted to give any update (closure of sorts) to the whole rear end pinion angle vs noise at highway speed.

Yes, much quieter.  However, I am still getting a little noise which I can confirm from other "Product review videos" is from the McLeod twin disc clutch. 

Other than that, good to go!  Thanks everyone for your input :0)

[cobracammer]

"Ix-Nah" on the whole closure thing from my previous post!  So this is how the story goes......

After install of the BMR adjustable upper control arm for the rear end, I would get a horrible knocking/ clunking sound going over bumps while coasting or slowing down (akin to possibly a loose strut noise).  Not only that, nut the howling/ squealing noise was still very much there.

Since the only change was the adjustable control arm, I swapped it back out for the stock unit and noise was gone!  In doing a little more light reading, it came to light that the BMR upper adjustable control arm is known for making that knock/ clunk if you don't use their custom frame bracket (and just use the Stock one).

A few weeks later, while out shopping, I decided I needed a few more tools which included a proper "angle finder".  When I got home, I jacket the car back up and placed it up on blocks so it was sitting at ride height with weight on the wheels.  Using my new angle finder, I wanted to find out exactly where my Pinion angle was and this time for sure!  The first place I measured was the Crank pulley.  I used a flat metal bar to span across the pulley from top to bottom and the angle finder showed 2.8 Degrees.  Then I wanted to get a solid reading off of the rear differential....  to do this, even though there are like 10 different methods online people use, I decided that removing the driveshaft and taking the reading off of the machines U-joint cap surface was the best bet.  With the driveshaft out of the way, I got 3.0 Degrees!  The pinion is pointing up past the transmission angle already by .02 just sitting still.  This would mean under power, I was probably at 5.0 Degrees while the transmission was still fixed at 2.8 Degrees.....  Yikes!  Stock upper control arm will not cut it.  I have to go back to the BMR adjustable, but this time had to order their $150.00 aftermarket bracket to avoid getting that clunking noise when going over bumps.  I just got the bracket in yesterday, and plan to do the install (again) this week.  Want to get the rear differential pointing down below the trans angle to either 0 Degrees to 0.2 degrees (that way under acceleration, with 2 degrees of upward movement, the trans and rear diff point directly at one another.   This seems like such a simple thing, but its had me going for a few months now.  LOL  What better way to learn!

Now to address the noise which started this whole journey.....  its not the twin disc at all. Its the ring and pinion howling at speed!  While I had the driveshaft out to take the angle measurement, I noticed quite a bit of play in the pinion yolk!  Not only do I knot believe there is supposed to be no play at all, but I think you need to show about 15 in lbs of preload to be able to turn it.  I could just take the yolk in my hand and turn it left to right about 1/2 to 3/4 of an inch in both directions!  It had no play in and out or up and down, but rotationally, I was getting quite a bit.

Not really sure how this happened as the car probably only has a total of 200 miles on it in total (?) between my drives and the Carfix episode.  But either way, it appeared a rebuild was necessary.  Yesterday I ordered a set of US Gear lightning series (the ones that are pre-broken in and you do not have to go through the break in procedure), a rebuild kit, all the pinion depth tools, analog in/lb torque wrench, extra crush collars, etc.... and I will be taking this on as well!  I maintained my 3.89:1 gear ratio with the new gears (forgot to mention).  Let you all know how it goes.

[machoneman]

"Now to address the noise which started this whole journey.....  its not the twin disc at all. Its the ring and pinion howling at speed!  While I had the driveshaft out to take the angle measurement, I noticed quite a bit of play in the pinion yolk!  Not only do I knot believe there is supposed to be no play at all, but I think you need to show about 15 in lbs of preload to be able to turn it.  I could just take the yolk in my hand and turn it left to right about 1/2 to 3/4 of an inch in both directions!  It had no play in and out or up and down, but rotationally, I was getting quite a bit."

Yikes, indeed. I'd venture that the pinion nut backed off (unlikely unless it was re-used and even then...) or the nut wasn't sufficiently tightened ( crush sleeve? or solid spacer?) in the first place. Once the carrier comes out, check the side bearings as well before it's torn down.

[cobracammer]

Thanks Bob.  Will do.  Confused as I purchased this 3rd member as a completed unit NEW!  lol  Let you know what I find.

[My427stang]

Always good to disassemble, but the side bearings will have positive stops on the adjusters.

I would just pull the pinion housing out, MUCH quicker, get the bearing preload right, and if the backlash looks normal after fixing that, run it, I bet it's fixed

Likely the lock nut was bad, or taken on and off, and just loosened up

[cobracammer]

Thanks Ross.  I may try that first, and then if its doesnt work, I will just pull the 3rd member and rebuild with all the new parts coming in.

Also, I just got done swapping out the BMR adjustable upper control arm and its corresponding bracket.  Its definately a pain in the  butt as it requires the saddle style fuel tank to be lowered to get the bracket out.

Anyway, all back together and this is what I have......  Trans angle is 2.8 degrees (pointing down from front to back).....  and now Rear differential is 0.8 degrees (pointing down from front to back).  I believe this will put me at a -2 degrees pinion angle.... thus putting the rear differential at 2.8 (front to back) with the 2 degrees of rotation under acceleration.

Getting there boys!  With all of these.... ahem.. experiences, the next project car should be a breeze!  HAHAHA

[machoneman]

Always good to disassemble, but the side bearings will have positive stops on the adjusters.

I would just pull the pinion housing out, MUCH quicker, get the bearing preload right, and if the backlash looks normal after fixing that, run it, I bet it's fixed

Likely the lock nut was bad, or taken on and off, and just loosened up

Unless the seller didn't tighten down the adjuster bolts!

[cobracammer]

Yea just from the noise when I turn the pinion yolk back and forth (1/2 to 3/4 inch play) , I get the feeling that the ring gear has moved away from the pinion..... and should be moved closer to get rid of excess ring gear backlash (I suspect) 

[machoneman]

Yea just from the noise when I turn the pinion yolk back and forth (1/2 to 3/4 inch play) , I get the feeling that the ring gear has moved away from the pinion..... and should be moved closer to get rid of excess ring gear backlash (I suspect) 

Yeah, until its out, hard to speculate. Would be cool to find that that the gears are o.k. save an tightening of the side bearings!

[Nightmist66]

Yea just from the noise when I turn the pinion yolk back and forth (1/2 to 3/4 inch play) , I get the feeling that the ring gear has moved away from the pinion..... and should be moved closer to get rid of excess ring gear backlash (I suspect) 

Only my opinion, but I suspect it would have to be side bearing related. The 9" has a rear support bearing and even if the pinion nut was loose, the rear support bearing should keep the pinion from cocking at an angle and increasing backlash. So, it should either have the same backlash it started with(bearings tight or pushed forward) or get tighter moving the pinion back into the ring gear if the nut is loose. I wonder if the locking tabs were installed on the side adjusters? I would plan on removing the whole 3rd member.....Can you wiggle the pinion yoke at all?