Mark, the way it is usually done is to place the engine at the same angle as
the pitch of the rear
end. Do not use the drive shaft as a guide, as the rear end and engine may be
at the same angle,
but in different planes. Usually GM products are about 1-3 degrees pitch
backwards from horizontal.
I set up my rear end this way, and then when I put in my motor mounts, I set
them so that I had a
2-1/2 degree pitch, measured by placing an electronic protractor on the carb
intake mounting face.
If you don't have a convenient way of measuring the angle, it can be calculated
by the formula:
angle in degrees (SIN) x 12 = height of the slope per foot
That will give you the slope per foot. Just punch in the angle on any
calculator that has trig
functions, then hit the SIN key and multiply the result by however many inches
you want to measure
the slope. For example, 2.4 degrees comes out to approximately 1/2" slope
every 12". So you could
shim a 12" level with 1/2" and that would be the pitch of the engine. Keeping
the motor and the
rear end at the same "pinion angle" will help extend the life of the u-joints.
For those that watch shows like Horsepower TV, I believe they used this method
on one of their
Wally / Templeton, MA
> How are you supposaed to position the engine to get the carb setting the way
> it should? I always thought you wanted the carb throat surface to be
> horizontal. But, if the TH-30's pan surface isn't paralell to the ground,
> won't this cause problems?
> Any feedback will be appreciated.
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959