Thread: to many angles!

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finally to the point of mocking up engine and trans in the frame that i built for my front fenderless model a,i am trying to set up carb pad angle and trans output angle, the intake i have has the carb pad angled so i assumed that you would set the pad level and that will put the trans at a good angle to work with the diff. i am trying to find out what angle ford designed the 460 to be mounted at and if it is ok to mount the engine at a slight angle for visual purposes, concerned about fuel floats and oiling and drive shaft angles, any input very much appreciated

First, set the body up at the angle it will be when the car is finished and on the road, level, down in front, down in rear, whatever. Once you have the body attitude like you want it, install the motor with the carb pad level. This will normally equate to about a 3 degree down-bubble on your angle finder when faced off a crank pulley or transmission output shaft (less yoke). Install the rearend with the pinion at a 1-2 degree up-bubble. This will leave 1 or 2 degrees for the pinion to climb the ring gear under cruising power and result in a 0 differential of angle between the crankshaft centerline and the pinion centerline as viewed from the side of the vehicle. When measuring for driveshaft length, have the car sitting on its tires with the suspension weighted. Easiest way is to put it on a drive-on lift, even though you will have to push it on by hand. That way, you can get underneath to measure the length of shaft you need. You should have the transmission yoke available and the pinion yoke installed on the pinion. Push the trans yoke into the trans as far as it will go, then pull it back out 5/8" to 3/4". Now, measure from the centerline of the trans yoke to the centerline of the pinion yoke. That is the measurement you will give the shop in order to make your shaft from scratch.

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Since the pinion is a set distance from the ground, set the body up at the attitude that you like, and then mount the engine /trans crank/output shaft at the angle necessary for the drive train and correct the carb angle as needed (if needed) as a final step-------

As Tech said...... He covered it all, in spades.

Nope-its backwards-------------

Originally Posted by jerry clayton

Nope-its backwards-------------

Jerry, I disagree. Tech says get the vehicle at ride height and attitude, whatever it's going to be, and then set the carb pad level, which is likely going to be in the neighborhood of three degrees down at the back, relative to the ground. Then set the pinion about two degrees tilted up. That's exactly what every driveline reference says to do to eliminate u-joint vibration and premature failures. Here's one from Inland Empire, one of the best places for custom drive shaft work - https://www.iedls.com/asp/admin/getF...&TID=28&FN=PDF

You don't build drivelines to the carb angles--------------you build drive line angles and then set the carb angle----


Can you imagine back in the day-------fender plaques not only showing cubic inches but also carb angles??????


427 with 6 * carb angle!!!!!!!!!!!!!!

Originally Posted by jerry clayton

You don't build drivelines to the carb angles--------------you build drive line angles and then set the carb angle----

Jerry, I absolutely respect your knowledge and experience, as I do techinspector1. However, I'm a little confused, won't the carb angle effect the driveline angle and wisa/versa? Can you please explain further.

So, how does one angle the carb; assuming the required transmission angle doesn't accommodate the carb: my first thought was to just angle - grind a pheonelic spacer, but then the bolts would need to be angled somehow.

Demano, sorry that your thread is evolving into such a discussion. The point is that we're not the OEM designers, so we have to live with what they put together for the line of vehicles that they were building, and don't have the luxury of setting the engine at whatever angle we want, and then "adjusting" the carb angle to bring it to level. Most OEM designs had the driveline at around a three degree downward tilt, tailshaft down, and then the carb angle tilted nominal three degrees pitched forward so that it was very near level on level ground. What makes sense to most of us is to set your motor mounts and transmission mounts such that the carb surface is level, making certain that the chassis is set up as you intend it to be in the final status - decide your tires, decide your suspension "attitude", and like Tech said at the get go,

Originally Posted by techinspector1

Once you have the body attitude like you want it, install the motor with the carb pad level. This will normally equate to about a 3 degree down-bubble on your angle finder when faced off a crank pulley or transmission output shaft (less yoke). Install the rearend with the pinion at a 1-2 degree up-bubble. This will leave 1 or 2 degrees for the pinion to climb the ring gear under cruising power and result in a 0 differential of angle between the crankshaft centerline and the pinion centerline as viewed from the side of the vehicle.

Now you can set it up to some other criteria, and try to figure out how to level your carb for best operation, but if you simply set it up like Tech advised you're going to find that your driveline angles are going to be at or very near what they were in the OEM design that your engine came out of, and that's pretty good in my book.

Two things----------carb angle is to the ground (mother earth?) Driveline angle is to the crankshaft, tranny out put shaft, rear end pinion centerlines and is to accomadate the necessary movement of the needles in the U joints to insure long life versa a short notching session--
The timing of the joints and workable angle range is necessary for a smooth vibration free operation.
The general rule of thumb about the pinion being a degree or so more down than the trans output is to accomadate the torque rotation moment on acceleration to an equal angle with the front shaft joint.


The issue of carb base angles----------manufacturers use some of the same base engine packages in cars to heavy duty trucks-the taller (and sometimes shorter wheelbase) of 4 x4 s will require a steeper down angle toward the rear pinion than say a Camaro or mustang--------in order to get the carbed engines to run smooth and effienctly they needed to be tipped to maintain float bowl fuel levels thru out a varing range of acceleration, cruise and deceleration /and/or heavy braking---------


So, if you take a 460 from a Lincoln you will probably have a different manifold carb base angle than on a 429 sourced from a heavy duty truck------


If your carb base is at an extreme angle and you end up with back firing on acceleration, blubbering /stalling on decal, you might need to put an angled base plate under the carb or take off the intake and machine the carbsurface a few degrees---------or yu could remove the seats, cut the floor boards out and remount the engine /tranny till the carb is level and then put up with vibration on acceleration, rapid U joint wear, occasional tossed drive shaft, etc, etc


Build the drive line angles/timing and level the carb if necessary last

Originally Posted by jerry clayton

.....Build the drive line angles/timing and level the carb if necessary last

Or another way, mock up your engine & tranny with the carb level, and then if you got your engine out of a big honking truck and you find that your driveline angle is more than about three degrees buy a new performance intake, because the one you've got is likely not going to be what you want anyway. Why make things difficult just because you can??

Roger-I couldn't find one word about carb base angle in that Inland Empire link--will you copy it for me ??

Originally Posted by jerry clayton

Roger-I couldn't find one word about carb base angle in that Inland Empire link--will you copy it for me ??

Nope, and I won't further hijack Demano's thread, either. He's got everything he needs to move his project down the line.

Demano, I hope you'll stick around and post again, and again, and again. Glad you're here, and hoping you'll hang in in light of the rocky start that you had nothing to do with.

Roger this is simply over carb base angle words which I don't believe Richard even pushed-
I believe he referenced that phrase as an initial get close starting point as he then wrote about using the bubble angle finder against the crank pulley---and about the same as Inland Empire did with putting it on the starter mounting area( only works gm ) You and I are the ones who have continued this and it seems to me that you are more inclined to push carb angle being a huge factor in a build than the proper establishment of driveline angles----------


Using the issue of carb base angle as the go to prime issue is about like going with windshield wiper mounting as the second item on the build list--------