Here's the deal, you know when you mock everything up to make sure it is spot on...... then you weld it and go to sleep and somewhere during your slumber gremlins come and re-weld everything in the wrong place? OK, I have a transverse leaf in a model a. Somehow I ended up with 7 degrees down on the pinion and 2 up on the tailshaft. I stuck a rod in the ****** and centered it up and the total worked out to be approx 5 degrees overall. Will I get a vibration with this setup? Please tell me no, because there's no turning back it was all welded solid last night. I swear it was right when it was all tacked together. 18 hours in the shop will do bad things to your judgement.
No, not a specific topic covering your exact problem, but threads covering just about every thing about pinion angles and driveshafts. You should be able to find an answer to your question. I think that even 5* is to much, unless you are using parallel leaf springs and plan on only running it at the drag strip and want to compensate for spring wrap up under hard acceleration. For daily driving I set up all the cars that I build at less than 3*. If you are using a ladderbar/ fourlink/fourbar set up or something like that than 1* to 2* is good. But that is just the way it works for me, maybe you'll be happy with some thing else.
I too goofed one time installing spring pads on a new rear in a '56 Chevy PU. I welded the pads on the rearend with the pinion up 3 degrees...I made the poor ***umption that when I sat the leafs down on top, the pad would be level...but once it was all bolted in I had the pinion up about 8*'s...never checked the ****** (4speed granny) as it was left in the original position. Anyway, I ran that rear for a good 4 years...maybe 20-25K miles without issues/vibrations/etc. But-insert disclaimer here-if I were mounting evrything up from scratch..i/e with the body off/etc., I'd start over and set things up right...but at the time being young and in a hurry worked out okay for me.
Actually, I have poured over the search feature. I was just hoping that someone had a similar situation and could offer some hope. I guess I am gonna hafta cut it off and start over. It has a total driveline angle of 5 degrees. I am running 36 Ford shortened boned with a tranverse leaf and the rear of the 36 hangers. Can I lessen the effects if I lower the tailshaft of the ****** or will this just amplify everything? I figured with all the 4wd pickups that are jacked way up, this wouldn't be an issue.
Here's a link to a good post: http://www.jalopyjournal.com/forum/showthread.php?t=268643&highlight=driveline+angle
http://www.streetrodderweb.com/tech/0203sr_drive_shaft_angles/index.html you should be able to figure it out using the same mathematical formulas as this article, or get it within reason
Well, I have cut of the brackets and started over. There's just no way around it. Thanks to those who had positive responses.
Looks like pinion angle is locked in at 7*. How much shimming to bring the tail shaft up from the 2*.
You mean theres anything but on the Hamb? Hmm, havent ever noticed. **Which reminds me, i need to post some updates of the truck
Root, The recent HAMB threads have had some good references and guides. If you can, try setting up w/3 degrees "offset", using the pinion vs the tailshaft, when viewed from above. (then you can align/parallel the two shafts when viewed horizontally) If there isn't enough offset in the pinion, viewed from above; then when viewed from the side, the pinion and tailshaft want to be parallel, but shifted, so that the driveshaft has a slight (perhaps 3) degree angle in relation to each coupling. This way the needle rollers occillate and lube as they roll.
Thanks guys. I'm having a heck of a time trying to keep all the pieces aligned for this project. I'll take a picture to explain. It's a bunch of monkey motion.
Set your frame at ride height, then set up the ******/engine angles and the pinion angles. What I just got done doing is installing an IFS (gasp) for my '36 and a triangulated 4-bar. Ofcourse the IFS will sit high in front without a load, so pulled the front coilovers and set the lower arms parallel...then put about 350/400 pounds on the rear of the ch***is to check/adjust ride height...set everything on jack stands to mimic my frame rake, then set the engine and ****** in for it's angle....and adjusted (before final welding) the tri-4bar as close as I could for 3*'s up on the pinion. It'll be so close, plus my tri4bar is adjustable, that it'll outlast me. Main thing is getting the rake at a known height/rake that you're going to have, even if your off a bit, you'll still be okay...you'd be suprised (with my angle gauge anyways) how much you can move things before degrees change.
Actually, I disagree with 3Mike6: I don't think you should set it at ride height, because when you are checking the angles with the car sitting on the ground, you're setting angles to a point in space, while the car is sitting on one particular spot. What I mean is, what angle is your garage floor at? What angle is your driveway at? What happens if you've got too little air in the front tires and they're low? When you put your angle finder on one of the parts, it is going to read that angle against a PLANE IN SPACE, not as it relates to the slope of the ground the tires are sitting on. Imagine your car is a bubble level,and you're setting all other angles against it. If the bubbles are off because the front of the car is sitting lower than the rear, all the other angles are going to be off by that much. Fine, if the slope of your ground is always constant, but if your garage floor slopes 2 degrees... Instead, set the car on jack stands and shim the jack stands until the frame rail is set at zero degrees. Then set your engine/transmission angle, and your pinion angle off of that. The Mopar Performance Ch***is Manual is a GREAT reference for setting dif angle, but I'm not sure it'll help with your buggy spring. (For other people reading this) They give the angles for leaf springs, 4-bar, leaf link and ladder bar suspensions, IIRC. Surely this info has been covered by a Tex Smith or "How to build hot rods" book? -Brad
There's a ton of misunderstanding on how angles R measured. If you measure like I do, there's usually vibration at or just past 4 degrees. That's the difference between the d'shaft tube, and either pinion or tailshaft(AT RIDE HEIGHT)
Brad54 is right...as are number of other responders who suggested there is myriad information on this subject on the HAMB. The salient point that Brad54 made is this: FORGET the "rake" or "angle" of the ch***is...driveline phasing has nothing to do with that. It is, always, the angular relationship between the imaginary line that extends out from the centerline tailshaft of the transmission and the imaginary line that extends forward from the centerline of the pinion. That being said, this angular relationship exists, both in practice and in theory, without respect to the overall at***ude of the vehicle. Your suggestion that "total" angle is 5 degrees is inaccurate...your "sum" angle is 5 degrees, based on 7 degrees down less 2 degrees up. In fact, the inclination of the tailshaft and the pinion should be equal but opposite, for a "sum" angle of zero. The OFFSET of these two imaginary lines should be a minimum of 1/2 degree and no more than 3 degrees,although that is sometimes hard to accomplish. Visually, think of your driveline as a parallelogram, NOT a t****zoid.
So let me make sure I understand as I am setting up a drive line for the first time. If i set my frame level side to side and front to back and then level my engine off of the intake and then set my pinion on parallel plane same degree as the tail shaft I should be right where I need to be? If that's the case it all makes sense now. Thanks!!
Close, but not exactly. By setting the frame total level, from that point on all of your dimensions will be true. When you put your angle finder or digital protractor on the pinion and the back of the transmission, you will have an true, accurate dimension. Otherwise, if your car is sitting on the ground, the whole car will be sitting on an angle (pick a number). Then, when you put the protractor on the pinion yoke, your reading will be off by whatever angle the car is sitting at, because the protractor doesn't measure angles against a fixed base, it measures them against a level line is space. As for the proper angles, DollaBill has an excellent explanation, and what he wrote is worth reading a couple times. I don't have the proper numbers, but I do know the Mopar book does, and I have a few people I can call who I KNOW know the proper angles. When I get to that point, I'll pick up the phone. For mock-up, I don't know if any of it is taken off the carb base on the intake--I believe it is taken off the centerline of the camshaft and/or the centerline of the tailshaft of the trans. -Brad
Man this is one thing I have read so much on and it always seems difficult to setup. It is so confusing, but i will level the frame and see how it goes. Thanks for the info.
But....a ladder bar suspension with a transverse leaf will be a little different...yes? The springs don't "wrap up" like on conventional setups.
Let's try to keep it simple. As your bars go through travel the pinion angle will change...it has to since the bars are solid welded to the axle. How much change depends on the length of the bars. Standard ladder bar/coilover setups like about 4deg pinion angle measures as the volumes on the suject say to measure it. Figure about 1-3deg change under load and about the total change of 4deg under full load or WFO. To get where you want to be, run the rear through it's designed travel and set it there. Don't be too concerned with "drop" of the axle in travel as you're not building a rock crawler. Consider that it will still have some "flex" designed into the system for something close at cruising speeds. And yes, I did get that your doing a buggy spring gig but the rules should still apply. I hope this makes sense. You may find you had it right after all. I've built enough drag cars to do this as a matter of course. My best setups were: Leaf spring/******* bars_ 7deg Ladderbar/coilover _ 2-4deg (depending on length and distance between the bars) 4 link _1-2 (again depending on length and distance) They always hooked hard and went dead straight. Always easy on parts too. Good luck and let's see the pics.
So, what you're saying is "make the frame level" (sorry I forgot to mention...and have just gotten used to...my shop floor is level//) So, you set your frame level, then set your pinion up/down 3*'s, and then sit the engine down 3*'s... So, I can see how things (relationshipp between engine/****** and pinon won't change)...but, now take your level frame, add say 5-8's rake to it...forget about the pinion for a minute...what happens to your engine rake? Well, you're now nose down 2 *'s (fine for a dragster as I undersatnd it)., but not right for a street drivven auto. I'll stand by setting the frame at proper ride hieght and rake (yes-discalaimer here, I don't have a flat tire, my shop floor is level...etc...in fact I do it without tires on the ch***is ) before you consider putting the engie in and setting the rearend up. Personally I want my engine/****** angle syitting back a few degrees, and I want this engine/****** sitting back those same degrees when I'm driving down the road (which for the most part is flat-ish)...so, that's why i set my engines/******'s in with the rame at ride height with the rake I'm going to run...don't see how you can accomplish the same thing, basing of "earth level". Maybe I'm wrong, but it's been working good so far
Why does it always seem that a guy asks a constructive question and instantly there are members who tell them to use the search? Maybe they have and had no luck. Instead of being a smart *** either help them or move on. For the time it takes to say " use the search funtion" you could've given him the awnser he was looking for or just save the guy some grief and just move on. I am fairly new to this stuff myself, im just a young guy trying to learn the craft the right way and to be honest i havent asked questions numerous times because its only a matter of time before someone has to pipe up and be a smart ***.
Pretty easy stuff, small block chev for example. Carb base is level front to back, tailshaft on transmission points down toward the floor three degrees, thats stock factory stuff, regardless of what you put it in, 32 ford or 54 chevy, At ride height the pinion on the diff points up three degrees, making the imaginary lines between the two exactly paralell. That means that through the u joints rotation, each joint turns the exact same amount and speed, meaning no vibration, if they are set differently, one will have to turn further and faster thru its rotation setting up vibration that can be felt as a hum in the car. Don't matter how you set up the ch***is, what kind of suspension you use, none of those things, all that matters is, tailshaft level, 0 degrees, pinion level, 0 degrees, tailshaft down three degrees, pinion up three degrees, tailshaft up three degrees, pinion down three degrees, no matter, as long as there is a paralell line thru the driveline. Both u joints have to turn the same amount and the same speed thru their rotation.
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