- Thread starter
- #141
Pulled the body off (again) to look into this torque tube situation. Need to relocate the muffler or possibly get a smaller louder one.
72 FJ40 Chevota Build
- Thread starter Tokamak
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- Thread starter
- #143
I'm sizing up a muffler that will fit sideways in front of the rear shocks and above the rear diff.
Tokamak, I have no engineering data to back me on this, but I'm wondering if your future frame flex will merely twist your straight tube until it cracks, where the original tube with it's multiple elbow bends had the ability to withstand the constant twisting ????
- Thread starter
- #145
Jim,
The tack I'm taking on this is that the stress is between the two tubes. That torsional stress is maintaining the stiffness. I see the original bent tube as a compromise since it was most likely bent to clear the e-Brake drum. Being bent the torque will be concentrated at the weakest points. A full straight tube will spread the torque along its full length. From the two pictures you can see that the straight tube transfers its stress to the other rail. The bent tube starts accumulating stress at the bends. The bent tube will fail before the straight tube. This is an apples to apples comparison between the two tubes not the actual stress seen in the field.
Disclaimer: I don't know anything about this s**t, I just have software that can figure it out for me.
The tack I'm taking on this is that the stress is between the two tubes. That torsional stress is maintaining the stiffness. I see the original bent tube as a compromise since it was most likely bent to clear the e-Brake drum. Being bent the torque will be concentrated at the weakest points. A full straight tube will spread the torque along its full length. From the two pictures you can see that the straight tube transfers its stress to the other rail. The bent tube starts accumulating stress at the bends. The bent tube will fail before the straight tube. This is an apples to apples comparison between the two tubes not the actual stress seen in the field.
Disclaimer: I don't know anything about this s**t, I just have software that can figure it out for me.
The original torque tube passes through both sides of the frame amd is welded at the inside and outside of the frame rail.
With 0 engineering and welding experience, it looks like the weakspot would be in the corner of the cut out. The birdsmouth in the picture and in the software is different. Will it perform the same?
With 0 engineering and welding experience, it looks like the weakspot would be in the corner of the cut out. The birdsmouth in the picture and in the software is different. Will it perform the same?
- Thread starter
- #147
The weakest point will be at a sharp transition but the yield strength at that point may be well above the stress placed on it in operation. My analysis is a comparison of the two configurations not the yield strength. I do not know what levels of stress are placed on the components in operation to determine the strength margin.
I plan on welding slightly above the original tube feed thru. I'll gain the connection of the frame pieces there and on the top of the frame rail. Should be good nuff.
I plan on welding slightly above the original tube feed thru. I'll gain the connection of the frame pieces there and on the top of the frame rail. Should be good nuff.
Boy, this torque tubs question is getting deep, could be we're all over-thinking. You also have to consider every other crossmember in the frame (and to some degree even the motor mounting) also add to the effectiveness of the torque tube relative to frame flex.
- Thread starter
- #149
What we really need is a discussion on tilted differential oil level. What have people done in the past? Is it an issue?
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- #150
I called Just Differentials (where I bought my gears and lockers). The guy there said that the stock oil volume will be fine. The differential is designed to have the ring gear throw oil up on the pinion bearing. My differential is at 6 degrees his is at 8 degrees and has no problems.
I satisfied with this answer.
On another subject of mufflers. I ordered a Walker 21548 Quiet Flow muffler with a Vibrant 1141 Ultra Quiet Resonator to put in front of the muffler
I satisfied with this answer.
On another subject of mufflers. I ordered a Walker 21548 Quiet Flow muffler with a Vibrant 1141 Ultra Quiet Resonator to put in front of the muffler
pinion bearing + lack of oil = early death of the bearing 
it will not be immediate ... but ... it will fail much earlier than expected... fine yes... great no ... IMHO
If it were me or a friends truck i would still use more oil than stock to bring the level up higher
did you remove the TRTT aka torque tube for clearance or was it actually interfering? why not put the stock tube in .... just moved further back to clear all ?
it will not be immediate ... but ... it will fail much earlier than expected... fine yes... great no ... IMHO
If it were me or a friends truck i would still use more oil than stock to bring the level up higher
did you remove the TRTT aka torque tube for clearance or was it actually interfering? why not put the stock tube in .... just moved further back to clear all ?
Back in the 1980's-90's when Harry High Rider Mini Trucks was the fad, these guys were lifted so high that their diffs were pointed darn near 50 to 60 degrees upward, and you bet they had pinion oiling problems.
- Thread starter
- #153
did you remove the TRTT aka torque tube for clearance or was it actually interfering? why not put the stock tube in .... just moved further back to clear all ?[/QUOTE]
JohnnyC,
Started out removing it to clear what was going to be the Disk E Brake. Changed to Cadillac calipers with e-brakes when the drive shaft disk got too expensive. Then I made some cuts on the tube to try and use it up side down as a transmission cross member. I didn't cut it flush so its an inch short. Moving it back makes it another inch shorter (frame taper). Hind sight, I could have left it where it was. Hate when that happens.
JohnnyC,
Started out removing it to clear what was going to be the Disk E Brake. Changed to Cadillac calipers with e-brakes when the drive shaft disk got too expensive. Then I made some cuts on the tube to try and use it up side down as a transmission cross member. I didn't cut it flush so its an inch short. Moving it back makes it another inch shorter (frame taper). Hind sight, I could have left it where it was. Hate when that happens.
- Thread starter
- #154
Got most of the exhaust figured out. This is the same muffler and resonator a friend installed on a '67 Mustang V8 and he said it was quiet.
Still waiting on a 180 bend for the input to the muffler. Welded in the body lift cross members. Will weld the torque tube after the exhaust routing is done.
Local muffler shop will bend a piece at the input to the resonator.
Exhaust will exit behind the tire on the drivers side.
Still waiting on a 180 bend for the input to the muffler. Welded in the body lift cross members. Will weld the torque tube after the exhaust routing is done.
Local muffler shop will bend a piece at the input to the resonator.
Exhaust will exit behind the tire on the drivers side.
Nice job on the exhaust! I really need to rethink mine, especially once I add back the torque tube.
Here's a dumb question. What does the resonator do?
Also, are you leaving in those square tube cross members?
I used you idea on my seat mounts. Still need to weld in the front legs and some angled gussets.
Keep up the good work! You're an inspiration for my build!
Here's a dumb question. What does the resonator do?
Also, are you leaving in those square tube cross members?
I used you idea on my seat mounts. Still need to weld in the front legs and some angled gussets.
Keep up the good work! You're an inspiration for my build!
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- Thread starter
- #156
Nice job on the seat brackets SMG. The square tube supports the body lift. I welded them in to help add more stiffness. Belt and Suspenders for the torque tube.
My buddy with the Mustang said he hated the muffler by itself cause it would drone when cruising down the road. He added the resonator and it absorbed some of the frequencies and/or noise that caused the drone and quieted the whole system down. Looking inside it, it just looks like a short glass pack muffler.
Is that a store bought console?
My buddy with the Mustang said he hated the muffler by itself cause it would drone when cruising down the road. He added the resonator and it absorbed some of the frequencies and/or noise that caused the drone and quieted the whole system down. Looking inside it, it just looks like a short glass pack muffler.
Is that a store bought console?
Relocating the filler plugs. Cut, turn then reweld.
- Thread starter
- #159
Tom,
Do you remember the angle of your diff is pointing up and the number of quarts of fluid now?
Do you remember the angle of your diff is pointing up and the number of quarts of fluid now?
I did this when I did my soa and the pinion angles were different front and rear but I kept the same height of the original lower thread to axle tube on each. No more than a quart each.