To expand on what causes the vibration when a Shaft and U-Joints are not run Parallel. A video will say more than I'm willing to write.
To expand on what causes the vibration when a Shaft and U-Joints are not run Parallel. A video will say more than I'm willing to write.
Get the harmonic balancer centered in the frame and the transmission tail shaft centered in the frame. A tape measure will work for that, you may have to jockey back and forth a little bit. Remember close is cool, you're not building a church and even if you were the only part anyone is looking at is that hot chick in the 3rd row.
Yea they are not building churches either. I hate to say this and hope that the persons who read this are not so offended that they turn to a different hobby but questions like this are pretty novice and some of the answers that we see are pretty novice as well. With time you learn to not sweat the little shit, and you learn the difference between the little shit and the important real shit.
I'm gonna do this for my project, and got a few question. If I install the rear end (parallel springs), set it up so that my flange is vertical. Make an flange with a thick wall pipe welded to the flange, that lines up with the gearbox plane, with a flange in the front. Like I have seen it done with "the old master" build from an old magazine. Then make sure the Carb flange is level. Secure it so that it's straight along the center line. Double check. Install frame mounts, with out rubber cusion/rubber mount. Remove line up tool, and put rubber cushions in. This is done with the care on the tires, not on the bench/work table. The basic Ideer behind mounting it up without the rubbers, is that I get it razed up one good inch or so vertically, keep my flanges parallel and get the U joints offset a little. I mean to critic of the OP methode, that seems good too. I just wants to know peoples opinion before I go do it. Sorry for the thread jacking.
Volvobrynk, The easiest method is to set you car at ride height/ride angle. Then set your engine in place and make the carb pad level in both directions with the bolted in place. You set your rear end with the pinion angle and the crank angle the same. When you are done with the car the carb pad may not be level front to back any more because of tire changes but close is cool. the "critical" measurement is pinion angle to crank angle and even it can be off a little bit. Ideally on a car that gets driven on the street you want the U joint to have a little kink in it, so that it has to work a little bit. this keeps the needles rolling so that they don't wear little grooves in the races. Sometimes we see articles about building dragsters where they use a bare block with a pipe sticking through the bearing saddles aligning the rear end up exactly with the crank center. These cars have the rear mounted solid and only go 1320 feet at a time. They live in a world that is measured in .001 second and every little bit counts. A street car needs to be a little more versatile and longevity is more important then getting to the end of 1/4 mile quicker then someone else. I think that sometimes we overthink things too much, end of the day it is just a car and all it really has to do is get us from point A to point B and be fun doing it.
Back to the plumb bob: Sorry, but the basic vertical line a plumb bob affords can be hung from any fixed base overhead. I've often wished for a sky hook when I was just a lad, working outside... Some of my less-learned cohorts used a carpenter's square, but on uneven ground.
But even though it was uneven ground everything was still square with the world. A friend of mine once built a motorcycle chassis with a string line a torpedo level and a tape measure. In a dirt floored barn. It was a testament to crooked and I ended up straightening it out (would have been easier to start over trust me). I had the opportunity to redo the spring mounts on a straight axle car one time too because the fella was pretty twisted when he welded them. Note to self, never visit Berkley before you work on your gasser.
So what you are saying is my Ideer will work, but it's yo complicated? I know dragster live a different life then any of my cars ever will. But I think that the Ideer in my head didn't seem that bad. And raising it afterwards would give me the kink in my U joints I need for everyday driving and it will make my setup more, fixed when lining it up for welding. And I can slap a square bar in between when welding, to prevent any warpage when cooling off. I just need to put a gearbox lifter under my drivetrain bolt the mounts to the drivetrain, tack it in and Bobs your uncle. There will go a little work in to making the bar with flanges, but I can used it for my SWV Volvo based slingshot project, if it ever gets of the ground.
They do. Check almost any MACHINED surface on an engine, trans or rear axle and you'll be surprised what you find... Also- if the engine centerline is offset BOTH vertically AND Horizontally from the pinion shaft input centerline- that is NOT 2 angles to deal with- it's still just ONE angle - it just happens to not be parallel to the ground. stand behind the vehicle and tilt your head to the side until the driveshaft "appears" horisontal to your vision and you'll see it's just "offset" by X number of inches. The plane in which it's off set does not matter-rick
There really are two separate angles, that should be measured and calculated, to arrive at a true operating angle, IF that's important to you. Many believe as you, but I gotta think the people who design and build U-joints should know what they're talking about, don't cha think? The link below may shed some light on the subject. Pages 7 through 10 should be of particular interest. http://www2.dana.com/pdf/J3311-1-DSSP.pdf
31'vick is right. Floor baseline, set up your stuff, you're done. Laser? Maybe. Plumb bobs? I have used them once or twice on back half cars but not often. Up until the 60s the driveline was dead center. Some time in the 60s all of them started moving the shit to the right side to gain real estate for other components. I mentioned this in the explorer rear axle topic. And yes, 3-4-5 or 6-8-10, all works to check square and I usually did that to create a perpendicular line on the floor for fore and aft measurements. The chalk line on the floor is best when you can spray some cheap clear over it so you don't brush it off. Every car I tubbed in the past was built at ride hgt, on the floor, baselines created. Never needed more than 1 or 2 flats on a bar to have it launch dead straight on any of them. Keep it simple. Don't sweat the petty, pet the sweaty instead. Yes, you want it right, sometimes it's so easy it seems like something is going wrong. Good luck, and novice question or not, good on you for asking. These things help others too sometimes.
Yes. but no. They are correct at how to calculate it when there's both verticle and horizontal offset. But it's just a mathmatical way of doing what you could also do by hand with an angle finder gauge (assuming the powertrain was mounted at angle in the car. If you unbolted the axle from the rear leaf springs and rotated it along the pinion gear axis while the drive shaft is still attached, you'd eventually line up the rear axle in the same plane as the drive shaft sits (when viewed from behind the car). Let's lock that rear axle at that angle with imaginary leaf springs. Now you unbolt your motor/trans mounts and rotate the engine/trans to the same angle as the rear. Because you rotated everything along the axis of the shafting involved-nothing's changed. Agreed? So put the angle finder on the driveshaft to pinion yoke or the driveshaft to trans yoke and you'll find that measurement matches spicer's compound offset calculation. It's still one plane/angle when viewed from the ujoint's perspective. -rick
Rick, I got a dizzy trying to follow your 'splanation! Seriously, I also used to think the same as you ( sorta ) until I learned more about U-joints and the fact there are two angles when there is a vertical and horizontal pinion offset. I'll stick with what the experts (Dana/Spicer) state and measure accordingly any compound U-joint angles to figure actual working angles.
If you remove the carb. you have a flat plane on the intake manifold. A torpedo level across this area would then give you a place to level your engine placement. This would assure level carb float bowls and oil being level in the oil pan and a level engine,transmission ect.
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