how long should a ramp be

[jamesnmlaw]

My new office comes with a garage. However, the garage entrance is 14" above ground level.

My 1969 911 has been lowered a little bit (clearing speed bumps require Xanax for me). So, figure about 4" of clearance as I've now installed a towing system that hangs down about 1" below bottom of front bumper.

I was thinking a 14' long ramp to keep the front & rear from scraping. Something like a foot of ramp for each inch of height from ground level to garage level.

Any suggestions?

Like I've always said, if I could have done the math, I'd have gone to medical school.

Thanks for help!

[Joe Bob]

Depends on what material the ramp is and if it flexes under load. I used to put my front bumper on with dzus fasteners.

[88911coupe]

I think the pythagorian thereom is going to come into play here...
Don't shoot the messenger.

[dad911]

Why not fix the grade to the garage with stone or paving?

[na2ub]

If your theory is 1 foot of ramp for 1" of height, why not just stick a plank of wood under the front and measure. Measure from the front of your front tire contact patch, to the front of the lowest point. That will give you your length. Then measure your plank of wood to see how many inches high it can be, at that specific length. That should be pretty accurate. Naturally, fudge the results a little in the direction of extra clearance.

For example, if it is 3 feet (horizontal) between the front contact patch of your front tire and the lowest point on the nose of the car, and the height of the lowest point is 4" as you guessed, then you could have a maximum of 4" of lift for 3 feet of length. This would give you 10.5 feet for 14" of lift.

It appears your nose it the deciding factor in ramp elevation, not the rear. Good luck