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TR2/3/3A Engine/tranny angle with the ground?
- Thread starter mgf
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Tom,
I'm continuing to create dimensionally accurate, 3d-dwgs for a Triumph TR3A. I understand about the variables you mention. If I understand it correctly, the front motor mounts set the front of the engine (in the vertical plane) & the "rear motor mount" (at the rear of the tranny), sets the rear of the engine/tranny. This is the one I'm trying to get verified.
In my mind, I'm extending the center line of the crankshaft through the tranny (at the stated angle), but not sure of this.
The drive shaft's universal joints & sliding coupling can evidently make-up any required vertical dimensional differences to accommodate the final connection to the differential.
Thanks,
mgf
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Although a slight down angle seems intuitively correct, I'm going to guess that the engine/transmission center line is parallel with the horizontal plane of the forward part of the frame, which is straight. I can't prove it but I can't find any evidence to the contrary and that certainly doesn't mean that I'm right. The Original Service Manual does show that the aft flat frame section appears to sit lower aft than forward, .19 inches in 29 from the frame plan. If my math is correct, that's about 1/2 degree, which would tilt the engine the same 1/2 degree.
Not much of an answer, I know. Perhaps someone who knows will chime in (or correct the math).
Tom
Not much of an answer, I know. Perhaps someone who knows will chime in (or correct the math).
Tom
Geo Hahn
Yoda
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I am pretty sure it slants noticeably - can't imagine it is an illusion. But then some magazine (Life or Look I think) went to a lot of trouble to prove a curve ball doesn't curve - though I suspect they never tried to hit one.
It's about 100° in the garage at the moment so not a great time of day to be out there - but a few minutes with a spirit level should reveal all.
It's about 100° in the garage at the moment so not a great time of day to be out there - but a few minutes with a spirit level should reveal all.
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Easiest way to determine this is with one of these placed on the valve cover of a stock vehicle:
https://www.homedepot.com/p/Johnson-Magnetic-Angle-Locator-700/100161689
There are generally a couple of reasons a motor won't be mounted horizontally to the ground; carburetor function and pinion angle. When you start swapping motors around, you need to think about these things. When the factory installed the motor, they took them into account. If the motor was angled downward, it was probably to get an acceptable pinion angle so the driveshaft ujoints wouldn't bind up. Someone with a stock car should be able to help you out.
https://www.homedepot.com/p/Johnson-Magnetic-Angle-Locator-700/100161689
There are generally a couple of reasons a motor won't be mounted horizontally to the ground; carburetor function and pinion angle. When you start swapping motors around, you need to think about these things. When the factory installed the motor, they took them into account. If the motor was angled downward, it was probably to get an acceptable pinion angle so the driveshaft ujoints wouldn't bind up. Someone with a stock car should be able to help you out.
martx-5
Yoda
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I just went out to the garage to do that, and it came up at slightly less then 4° on a level garage floor. I didn't check the tire pressures and besides, I've got an HVDA conversion. It has a different tranny mount that may make the angle different from stock, but knowing Herman, I doubt it would be far off.
