360 Magnum with 42rh install angle question.

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Truckie

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I’ve got the engine and transmission in, but haven’t built a crossmember yet because I’m unsure on what to do about intake and transmission angles. I’m using the stock efi on the 360. I have the chassis level based on the inside the door on the rocker panel. I took angle readings at several different spots for the heck of it. I’ll attach pics of the readings and list them below. All degrees are downward front to back (lower on driveshaft end than crank pulley end)

Top of intake: 2.1
Thermostat area of intake: 2.1
Crank pulley: 3.2
Top of timing cover: 0
On output shaft on trans(on the splines): 1.8
Along top of stock valve covers: 2.1

I’ve read several threads saying the top of the carved intake should be level when chassis is level and that would put the transmission output shaft at about 3 degrees down. I can’t find anyone talking about angles for the stock efi. Any help would be appreciated.

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Those readings are not necessarily accurate, at least some of them. Pulleys can be bent, and you show the angle reader on the output shaft which "wiggles" with no support with no yoke in place Also on such items if the angle finder is not exactly at the top of the pulley or shaft, it will not read correctly, either. In other words the angle finder axis 90 to the angle you are reading must be "plumb"

There are a few things that are either parallel or perpendicular to the true crank centerline Some may not be accessable easily. Water pump/ timing cover face (machined surface after gasket is cleaned off), crank snout before you put the balancer/ pulleys on, and the pan rails, either engine or automatic if properly mounted. Some U joint caps are flat, so if you have a yoke with a U joint in, you can check off one of the caps. Again, make sure it is rotated "plumb" either top or bottom

Without checking such as the pan rail against the TB mount, I have no idea if they the TB mount is on crank centerline

Any cast (not machined) surface such as the top of the timing cover ---is suspect
 
Those readings are not necessarily accurate, at least some of them. Pulleys can be bent, and you show the angle reader on the output shaft which "wiggles" with no support with no yoke in place Also on such items if the angle finder is not exactly at the top of the pulley or shaft, it will not read correctly, either. In other words the angle finder axis 90 to the angle you are reading must be "plumb"

There are a few things that are either parallel or perpendicular to the true crank centerline Some may not be accessable easily. Water pump/ timing cover face (machined surface after gasket is cleaned off), crank snout before you put the balancer/ pulleys on, and the pan rails, either engine or automatic if properly mounted. Some U joint caps are flat, so if you have a yoke with a U joint in, you can check off one of the caps. Again, make sure it is rotated "plumb" either top or bottom

Without checking such as the pan rail against the TB mount, I have no idea if they the TB mount is on crank centerline

Any cast (not machined) surface such as the top of the timing cover ---is suspect
Front of the timing cover with gasket cleaned off is 87.9 degrees so that would mean the top of the intake where the throttle body mounts is perpendicular to the machined front of the timing cover. I put a yoke in the transmission no it has a nearly identical reading to the top of the intake
 
Those are of the angles of concern but more so at the nose of the axle housing and the trans tail shaft where the angles should be corrected to prevent drive line vibration.
 
Back before the days of fuel injection when they used floats inside the carburetor they wanted the carburetor to sit parallel to the ground standing still.
You will notice on the old intakes some of the new ones also, that the front end is lower than at the rear of the carb mounting pad. This really shows the angle of the engine and transmission as mounted in the car.
I have not noticed with the kegger intakes there being that angle that the old manifolds had that mounted carburetors.
 
Those are of the angles of concern but more so at the nose of the axle housing and the trans tail shaft where the angles should be corrected to prevent drive line vibration.
Ok. What are your recommendations for tail shaft and pinion angle? In case it matters I am using the 8.8 Ford rearend.
 
Back before the days of fuel injection when they used floats inside the carburetor they wanted the carburetor to sit parallel to the ground standing still.
You will notice on the old intakes some of the new ones also, that the front end is lower than at the rear of the carb mounting pad. This really shows the angle of the engine and transmission as mounted in the car.
I have not noticed with the kegger intakes there being that angle that the old manifolds had that mounted carburetors.
I was kinda thinking the angle might not matter so much with efi since there are no floats to deal with.
 
I was kinda thinking the angle might not matter so much with efi since there are no floats to deal with.
.
I agree. My thinking was to use the carb mounting pad of the old intakes to determine what the angle of the engine and trans should be sitting at, at it's final mounting place.
 
Those are of the angles of concern but more so at the nose of the axle housing and the trans tail shaft where the angles should be corrected to prevent drive line vibration.

To be clear, the machined face of the timing cover (perpendicular) and the actual pan rails ARE the shaft angle. The problem with the "shaft angle" is as I started to say........you can't measure it absolutely accurately when it's slopping around loose at the rear of the trans.

OP what you want, in the end, is for the axle pinion shaft and the crank centerline (which again IS the transmission shaft) to be PARALLEL when the car is under power. You have to use a bit of "cheating" to allow for spring wrapup and suspension movement. Most people set the axle a couple degrees below the crank centerline to start, and it should "wrap up" under hard pull

Measure this with weight on all 4 wheels, level surface, and proper weight in the car, engine trans, spare, gas, etc. Even a driver if you can muster that
 
To be clear, the machined face of the timing cover (perpendicular) and the actual pan rails ARE the shaft angle. The problem with the "shaft angle" is as I started to say........you can't measure it absolutely accurately when it's slopping around loose at the rear of the trans.

OP what you want, in the end, is for the axle pinion shaft and the crank centerline (which again IS the transmission shaft) to be PARALLEL when the car is under power. You have to use a bit of "cheating" to allow for spring wrapup and suspension movement. Most people set the axle a couple degrees below the crank centerline to start, and it should "wrap up" under hard pull

Measure this with weight on all 4 wheels, level surface, and proper weight in the car, engine trans, spare, gas, etc. Even a driver if you can muster that
I believe I have read that the factory recommends 2-4 degrees down at the tail shaft. So if I set the tail shaft at 3 degrees down, does it make sense for the pinion angle to be 0 degrees? That way when it’s under power the rearend can wrap up to about 3 degrees pinion angle?
 
I believe I have read that the factory recommends 2-4 degrees down at the tail shaft. So if I set the tail shaft at 3 degrees down, does it make sense for the pinion angle to be 0 degrees? That way when it’s under power the rearend can wrap up to about 3 degrees pinion angle?

In theory ^^^^

3° down at trans tail shaft
3° up at rear pinion angle

When under power is good, allow a degree or 2 for rear end wrap up when under power.

So the more power and the harder you drive figures into your wrap up degree guess.

Want the angles equal when under power.

Good info outlined in this screen shot below.

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IMO, in an A-body
you will need to get the front of the engine as low as is possible, and the back of the trans up as high as is possible, going towards but not past, parallel to the rockers;
then deal with the rear driveline angles; which are; driveshaft to trans and driveshaft to pinion, and have nothing to do with the horizontal.
IMO having the engine at ~2* front high with the rockers leveled in side view, is gonna be close enough to work with. I would mock it up from there and see where the back comes in.
 
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