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Discussion Starter #1
How many degrees of engine tilt is the max for a sbc? I know 3 is what is ideal but I need to get more engine tilt in order to reduce the drive shaft angle. Also, what is the max for an angle on a typical driveshaft setup? I know that 3 again is ideal but whats the max? 10 degrees? Thanks for any and all input!
 

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boatbob2
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engine tilt

hi,put a level on the carb flange,should be level side to side and front to rear.if you need some adjustment,either lower the engine in the chassis,or find an angle plate to correct the level. im boatbob2
 

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Why driveshaft angle concern ?

For the ujoints to work correctly the engine tilt (trans shaft angle) should be the same as the pinion angle of the rear. If trans is 7' down the pinion should be 7' up. The engine/trans doesn't know that it's tilted except for the fluids. The driveshaft angle is not a big issue unless you are tring to get clearance or something.
What type of vehicle are you working on? With a little more info maybe we can help you out some more.
 

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Save a horse, Ride a Cowboy.
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Ideal is zero, but that is not feesible with suspension travel and axle twist. There seems to be a consensus that anything more than 4* beats the u-joints out.
 

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Discussion Starter #6
Thanks for the replys everyone!
The frame is a 47 ford pickup and the motor is sbc/th350 and the rearend is a bronco 9" with ladder bars and coils. With the frame level, I have 6 degrees on the motor and Im setting the rearend to match, then at the height of the motor in relation to the rearend- the drive shaft sits at 11 or 12 dergrees. So Im figuring that makes for about a 6 degrees of driveshaft angle or U joint angle. With the wheels on, the frame sits higher in the back at about an increase of 2 or 3 degrees so if I subtract that from the motor angle, the motor should sit at about 3 or 4 degrees(not including the manifold tilt which should now be level or 1 degree tilt back). The driveshaft/ujoint angle decreases when the rear suspension compresses so Im really hoping I got this all in an "OK" range. What do you fellas think? Thanks very much again for all replies! :evil:
 

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Hey Jimmy,
It all sounds OK to me. It sounds like you have it figured out. Also the longer the ladder bar is the less the angle changes during travel.
4x4 trucks have alot of driveshaft angle and they don't beatup U joints real bad. They may wear quicker than a car but, it's not a major difference.
Are the back of the ladder bars solid or adjustable?
While you're fabricating put yourself a couple driveshaft saftey loops on the truck.
 

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Member - AMC/Rambler "guru"
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If you're having trouble with the driveshaft angle, you can set the rear u-joint at 0 degrees and put all the angle at the front -- provided the angle isn't to much (6-7 degreeshould be okay). If you need more angle, say 10 degrees or so, you'll need a double cardan CV joint in the front (looks like two U-joints back to back). That's the "tricks" a lot of lifted trucks use. My brother used to be into 4x4s, set his Mustang V-8 up with 0 in back, and whatever it sits at in front. He's had no vibration problems with a built 302 (65 Mustang notchback).
 

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Here is a link to a thread with the chart showing maximum u joint operating angle for a given rpm. Go to post 2.
http://www.hotrodders.com/forum/tro...tion-18566.html?highlight=max+operating+angle

If you want to run the rear end to driveshaft oprating angle at 0, then you would do well to have a double cardan at the trans. That would make the angles found there be split between the 2 joints in the double cardan, and they would cancel out any vibration. IMO 6* is too much for a single, and if you ran a double, it would put each u joint in an acceptable operating range.

There were several good links to driveshaft diagrams in the KB, but the websites that held them seem to have been rearranged. I try to keep from citing other posts as a source of info, but I know that the info on that one originally came from a reliable source.

Later, mikey
 

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engine tilt

I have a similar question. I am converting from a Muncie 4 speed to a th400. So I need too make a new cross member. Should the carb be 0 degrees or should I have some downward take on carb. Any input would be great thanks.
 

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XNTRIK nailed it in post #5. In the early years of automobile production, bodies were higher up off the ground and engine/transmission packages were laid in at zero degrees. As cars became longer and lower, the engine/transmission package had to be angled down to provide footroom/legroom for the front seat passengers and driver.
 
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