Not That Bob
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Before we start, please try and keep this post on track.I will answer any question I am able but if they are about a specific vehicle not "theory", please open another post.
The laws of physics are the same for a Ferrari and a F150. In my case, I will be using my 1985 S10 extended cab 4x4 as an example.
You need to walk before you run,so we are going to start very basic (crawl) and work our way up.
You can't get there, until you know where here is. What this means is you need a good baseline.
In this case, scaling your vehicle. Go to the local scrap metal yard, truck stop etc and have your rig weighed.I always have mine weighed with the driver since it is rarely driven without one! Also have gas tank between 1/2 to 3/4 full. If you rig is done, have it loaded in the way it is mostly driven.
Drive on the scale halfway and get the front axle weight, drive to the middle, get full weight and last drive half the way off to get the rear axle weight. Some older scales give inaccurate reading when you are partially on the scale. Use those numbers to figure a percentage and apply that to the total.
There are many other factors but we will start with front/rear weight distribution since now we have that information.
I am sure everyone has heard of the mythical 50/50 weight distribution. Performance car advertising really push this but the reality is most vehicle will do better with something different then 50/50.
I prefer a slight rear bias for weight, say 45/55 on front engine,rear drive platform. Tough to achieve , but the closer you get the better. My S10 is just about the worse platform/drive-train layout you can start with. Not scaled yet, but most likely in the 65/35 range.
As an example, say a total weight is 4000#, so 2600# is supported by the front axle, 1400# the rear. Each front tire supports 1300#, rears only 700# each. This partially explains why pick ups are tailhappy, over-steering beasts.
If we were magically to change that to my 45/55, the front would now support 1800# and 2200# for the rear, much more balanced. See diagram.
Adding weight to a vehicle is evil, but when trying to make your rig more livable, a necessary evil. Added weight makes the vehicle harder to accelerate, harder to stop, harder to control. It can help with traction. It is also evil in that adding weight begets more weight causing use of Heavy Duty (heavier) parts. When possible use the lightest part you can without sacrificing function and safety.
Since we are adding weight, lets use it to out advantage or at-least not make thing worse!
The attached diagram has colored boxes. The red box(s) are where you want to avoid adding weight, yellow is ok, green is best. Again do the best you can, its not practical to add the row a cabinets down the center of your living space but you can add weight below deck in this area. A little here, a little there adds up. Try and look at the whole.
When does adding 150# = 208#? When you put it in "outside the axles".
On my S10 I am considering adding a S10 BLAZER gas tank as a auxiliary tank . It would be mounted right behind the rear axle in the stock Blazer position. Total weight, tank, brackets and fuel would be 150#.
Now here is where it gets tricky, since it is behind the rear axle you have to visualize it mounted at the end of a bar with the other end attached at the rear axle center-line. That bar is a lever.
There is a formula based on distance that I will not go into now but the 150# in this position, adds +179# to the rear axle and removes - 29# from the front axle. Total change 208#.
I cringe when I see a huge overhang with 20 gallons of gas cans, a spare, propane tank, etc hanging off the back of a vehicle. At-least if you a forced to do this, it helps add rear weight.
Ok, that's one part of the overall, going to stop here for now.
Fire away.
The laws of physics are the same for a Ferrari and a F150. In my case, I will be using my 1985 S10 extended cab 4x4 as an example.
You need to walk before you run,so we are going to start very basic (crawl) and work our way up.
You can't get there, until you know where here is. What this means is you need a good baseline.
In this case, scaling your vehicle. Go to the local scrap metal yard, truck stop etc and have your rig weighed.I always have mine weighed with the driver since it is rarely driven without one! Also have gas tank between 1/2 to 3/4 full. If you rig is done, have it loaded in the way it is mostly driven.
Drive on the scale halfway and get the front axle weight, drive to the middle, get full weight and last drive half the way off to get the rear axle weight. Some older scales give inaccurate reading when you are partially on the scale. Use those numbers to figure a percentage and apply that to the total.
There are many other factors but we will start with front/rear weight distribution since now we have that information.
I am sure everyone has heard of the mythical 50/50 weight distribution. Performance car advertising really push this but the reality is most vehicle will do better with something different then 50/50.
I prefer a slight rear bias for weight, say 45/55 on front engine,rear drive platform. Tough to achieve , but the closer you get the better. My S10 is just about the worse platform/drive-train layout you can start with. Not scaled yet, but most likely in the 65/35 range.
As an example, say a total weight is 4000#, so 2600# is supported by the front axle, 1400# the rear. Each front tire supports 1300#, rears only 700# each. This partially explains why pick ups are tailhappy, over-steering beasts.
If we were magically to change that to my 45/55, the front would now support 1800# and 2200# for the rear, much more balanced. See diagram.
Adding weight to a vehicle is evil, but when trying to make your rig more livable, a necessary evil. Added weight makes the vehicle harder to accelerate, harder to stop, harder to control. It can help with traction. It is also evil in that adding weight begets more weight causing use of Heavy Duty (heavier) parts. When possible use the lightest part you can without sacrificing function and safety.
Since we are adding weight, lets use it to out advantage or at-least not make thing worse!
The attached diagram has colored boxes. The red box(s) are where you want to avoid adding weight, yellow is ok, green is best. Again do the best you can, its not practical to add the row a cabinets down the center of your living space but you can add weight below deck in this area. A little here, a little there adds up. Try and look at the whole.
When does adding 150# = 208#? When you put it in "outside the axles".
On my S10 I am considering adding a S10 BLAZER gas tank as a auxiliary tank . It would be mounted right behind the rear axle in the stock Blazer position. Total weight, tank, brackets and fuel would be 150#.
Now here is where it gets tricky, since it is behind the rear axle you have to visualize it mounted at the end of a bar with the other end attached at the rear axle center-line. That bar is a lever.
There is a formula based on distance that I will not go into now but the 150# in this position, adds +179# to the rear axle and removes - 29# from the front axle. Total change 208#.
I cringe when I see a huge overhang with 20 gallons of gas cans, a spare, propane tank, etc hanging off the back of a vehicle. At-least if you a forced to do this, it helps add rear weight.
Ok, that's one part of the overall, going to stop here for now.
Fire away.
