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View Full Version : Short Wheelbase Vs Long Wheelbase Theory


DJPimpFlex
06-20-2006, 06:50 PM
Ok to start, this is just a theory thread. It is NOT S chassis specific, or any chassis specific, just a thread to see what the benifits of each are.

From the research that my friend and I have collected this is what we have come to see so far.

1. . By my research shorter wheelbases transfer more weight forward or back during braking and acceleration causeing less traction than in a long wheelbase.

2. Shorter wheelbases have more steering responce especially noticable at higher speeds. This inturn requires more steering sensitivity from the driver ofcourse.

3. They also have a faster break away when losing traction.

4. Havent gotten to the bottom of this yet but I have a theory that the rear wheels will travel a shorter distance around a turn as the wheelbase gets longer. That would implicate a change in tire loads.

5. And assuming 1 is correct, would that mean that as you brake you are transfering more weight to the front tires, meaning that you gain more contact patch, and you are less likely to understeer?

6. Since shorter wheelbase adds steering responce this would require less steering during cornering thus increaseing lateral traction.

Just wondering some opinions. My friend is looking to build a new car, and hes deciding between a few and wheelbase is one of the main differences.

DJPimpFlex
06-22-2006, 12:11 AM
so no one knows anything more about wheel bases? WTF

chlatboy
06-22-2006, 02:52 AM
Ok to start, this is just a theory thread. It is NOT S chassis specific, or any chassis specific, just a thread to see what the benifits of each are.

From the research that my friend and I have collected this is what we have come to see so far.

1. . By my research shorter wheelbases transfer more weight forward or back during braking and acceleration causeing less traction than in a long wheelbase.

2. Shorter wheelbases have more steering responce especially noticable at higher speeds. This inturn requires more steering sensitivity from the driver ofcourse.

3. They also have a faster break away when losing traction.

4. Havent gotten to the bottom of this yet but I have a theory that the rear wheels will travel a shorter distance around a turn as the wheelbase gets longer. That would implicate a change in tire loads.

5. And assuming 1 is correct, would that mean that as you brake you are transfering more weight to the front tires, meaning that you gain more contact patch, and you are less likely to understeer?

6. Since shorter wheelbase adds steering responce this would require less steering during cornering thus increaseing lateral traction.

Just wondering some opinions. My friend is looking to build a new car, and hes deciding between a few and wheelbase is one of the main differences.

Hahaha. You got some good points there. This might explain why smaller cars lke the miata are so good for autoX and what not.

Your points seem to be pretty well thought out. Try driving two cars to get the real feel of your theory. IE. A miata and a soarer since htey are kinda on different ends of the spectrum.

DJPimpFlex
06-22-2006, 03:00 AM
^yea I owned a Miata and it seems to be just that way compared to my S13's.

RightWheelDrive
06-22-2006, 03:16 AM
The way I see it is the comprimise between high speed stability (long wheel base) and low speed agility (short wheel base). This, in turn, just means a comprimise between understeer(long wheel base) vs. oversteer(short wheel base). Given the same tires in the back, the longer wheelbase would have a longer moment arm to resist the rotation of the car. The friction from the tires are able to stop the rotation of the car much more efficiently, thus, giving you more understeer and stability at high speeds. This is why cars have 4 wheel steering for lower speeds, to shorten the turning radius which gives the same effect as a shorter wheel base. The opposite happens when there is a short wheelbase. Here is a picture I made really quick to illustrate my point. The longer the red line, the easier it is for the tires to stop the car's rotation.

http://i55.photobucket.com/albums/g142/lamchops208/diagram-1.jpg ms paint + laptop touchpad FTW!!


As far as braking goes, there are many more factors that come into play but the same principle applies. With a longer wheelbase under braking, the rear of the car lifts and takes weight off, reducing stopping power. The farther away the rear tires are from the front tires, the more they will lift up during braking which affects braking ability. The center of weight of the car also has a lot to do with it so its hard to say.