Crankshaft centerline

[altered 09]

I am getting close to installing the motor and transmission. I understand pinion angle and that is not the question. What I am asking is, do I set the motor (crankshaft center line) level or a few degrees drop?
Ideas? Opinions? Bad experiences?

 

[kookie2007]

The whole idea behind pinion angle is to line up the centerline of the engine, transmission, and rear end as much as possible at ride height. The reason for this is U-joints tend to perform poorly with large angles of deflection. Most production cars have the engine/transmission tilted back about 3 degrees to accomplish this. With the engine in the frame, the centerline of the crankshaft is usually higher in the frame than the transmission output shaft and most of the time the rear end pinion is lower than the frame rail. I would shoot for as straight a line as possible between the three components as you can get at ride height. Just my thoughts and I'm sure someone here will have some pointers as well.
Larry

 

[fluidfloyd]

Here are a few links to several experts in the driveline world. Pretty much all say the same thing so look through it and make your choice.
Good Luck.

George

Mark Williams Enterprises - Driveshaft Technical Information

Tom Wood's Custom Drive Shafts - Driveline 101

How To Use Tremec's Driveline Angle Finder App - Get Your Angle On

Driveline Operating Angle Calculator

 

[2old2fast]

This topic has been beat to death here & elsewhere . My $02 , you want the engine level w/the ground , that way your sidepipes look the best , pinion angle should be equal & opposite , the driveshaft should be set so there is 1-3 degrees "working angles' , if you don't have working angles , the needle bearings in the u-joints never rotate which leads to premature failure
dave

 

[fluidfloyd]

This topic has been beat to death here & elsewhere . My $02 , you want the engine level w/the ground , that way your sidepipes look the best , pinion angle should be equal & opposite , the driveshaft should be set so there is 1-3 degrees "working angles' , if you don't have working angles , the needle bearings in the u-joints never rotate which leads to premature failure
dave

Dave...
You are right about beating an issue to death. And for most all street applications you are dead on the money. Lots of folks set the carburetor base level but I don't think it matters to much. If that was a problem you would need to live on the Salt Flats. I live in the mountains and still have a carburetor on my 1 ton truck. Never had any problems. The FI system will run inverted I believe. Pretty basis stuff.

 

[railroad]

If you are running a carb and intake, you can use the carb pad for horizontal surface.

 

[Bowtie T]

Isn't that why most intakes have some pitch too them so when the engine is sitting back 2-3* the carb will be somewhat level?

 

[choppedtop]

I realize that you have to start somewhere to set your engine at some kind of angle, preferably level at the carb surface on intake. Like Floyd said, I drive up and down some very steep places, even through ditches at times to get into a good parking place, and never experienced any odd running issue. How about all the older Jeeps, and VW buggies that do all the cool stuff?

 

[2old2fast]

To put a visual aid up for this 3* thing , the max slope[grade] on US interstates is 7% , that's roughly a 4* incline , running up & down hills on interstates does not affect a carbed vehicles operation . The 3* factory thing is more about packaging , keeping the engine above the crossmember while not taking too much interior floor space ..
dave