Quick!!! Someone tell me the height vs track width rule

I need to know the height vs track width ratio ASAP. I found a cheap , tallish vehicle that could be a lateChallenge entry.

Height measurement has to be equal to or less than the track width measurement. Note track width is not outside to outside of the tires. You can look up the track width of most vehicles online.

Track must be wider than height. 

For the Quest Van the 2" wheel spacers on each side gave me 4" more of track keeping me legal by .7"

I just used the manufacturer's data on height and track. 

Also possible, a 2" shorter tire will reduce your vehicle height by 1" 

Thanks guys. 1:1 ratio it is.

another quick method to check track is inside of one tire to the outside of the other tire on the same axle. it gets the same result without having to find tread centers.

if the tires on both wheels of an axle are the same, then you may be able to measure to common tread block locations across the axle as well.