the best wheel base for racing
- Thread starter noceros
- Start date
BiggJim
I Hate Rules - UTVUnderground Approved
About 130" or so...oh, and 800 hp...just sayin'.
That would be nice....the we could retire the golf carts?
TNT
Banned Por Vida
You’re making a lot of crude assumptions. Wheel base is not the only variable that establishes stability and control. As much of a concern is CG location, sprung and un-sprung weight distribution, roll axis, etc….you can have a short wheel base and more stability than long, and less total weight. For example, a lower more centered cg car will have more stability and shock control than a higher one, if you want the best of both worlds take a shorter WB lower and center the CG, keep the distributed weight and moment arms(fwd/rear, to CG) down.
TNT
Banned Por Vida
Not at all if your rebuilding which I assumed he was.
TNT
Banned Por Vida
Agree, it is an interesting subject tho and VERY complicated hate to say. You can see the battle so far with Articat1000 vs XP900, with the Cat placing the rider closer to the “low CG”, as well as the bulk of the weight the engine mid-chassis, still leaving a whooping 13 inches of ground clearance, 90 inch WB, 1300 lbs.
XP900 has an 81 inch wheelbase, 1190 lbs, same ground clearance.
Hard to say without knowing exactly where the CG is on both cars whom the winner is, all we can say is that whomever knows how to optimize their Cg with respect to their dry weight, wheel locations, reliability, and cost will be the clear winner. Not an simple task my friend.
http://www.polaris.com/en-us/ATV-RA...s/RANGER-RZR-XP-900/pages/Specifications.aspx
http://www.atv.com/specs/arctic-cat/utility/2012/wildcat/1000i-h-o-/detail.html
XP900 has an 81 inch wheelbase, 1190 lbs, same ground clearance.
Hard to say without knowing exactly where the CG is on both cars whom the winner is, all we can say is that whomever knows how to optimize their Cg with respect to their dry weight, wheel locations, reliability, and cost will be the clear winner. Not an simple task my friend.
http://www.polaris.com/en-us/ATV-RA...s/RANGER-RZR-XP-900/pages/Specifications.aspx
http://www.atv.com/specs/arctic-cat/utility/2012/wildcat/1000i-h-o-/detail.html
TNT
Banned Por Vida
Kyle, stick to rock crawling where you shine.
To the serious racer everything matters. I have seen B class riders smoke A class just based on their set up and tech knowledge or team.
You racers have to understand weight and balance and how it affects stability and control, then you'll be ahead of the game and the answer is not always more wheel base and weight that will need more power.
The big weight 'distribution" ticket items are the rider(s) and motor, the closer they are to the CG and/or centralized(like Aritcat claims) the less the arm or distance to the CG, the more shock control and less impact to the driver. If you have no control of your CG in the vertical direction, your car feels fwd heavy or lawn darts for example, and you want to move the CG rear dynamically, then add more (fwd of CG, and as close to the CG as possible) wheel base w/ light weight material/designs, and visa versa. Arm pivot locations and swings have a large impact on sprung weight, but now we get too complicated.
Time for a brew it's Friday
Thanks for all the comments. We raced the Mint 400 want to race vtr. been seeing all the 4 seaters(switch to 2) racing. just wondering if the longer suv handles through tight rough terrain.
my center of gravity is pretty low. I have 13" clearance with 83" wb . my car is a 06 rhino with a rx1 engine handles very good up to 75 mph. want to run 95-100 mph. I want to extend either 10 or 12", lower the rear bars 6 to 8", lower my spare tire & add a bumper. change out the light bar to led (save about 25-30lbs overhead). hope to retain my low speed handling & gain high speed handling. Rich
my center of gravity is pretty low. I have 13" clearance with 83" wb . my car is a 06 rhino with a rx1 engine handles very good up to 75 mph. want to run 95-100 mph. I want to extend either 10 or 12", lower the rear bars 6 to 8", lower my spare tire & add a bumper. change out the light bar to led (save about 25-30lbs overhead). hope to retain my low speed handling & gain high speed handling. Rich
TNT
Banned Por Vida
Rich, need more detail on your issues above 75 mph?
Hard to compare any car to another there are so many variables that affect handling.
If one were to take a ball and call it a CG it is easy to move in any direction. Now position it in four tires, centered then the handling is symmetrical around the CG axis, lateral, longitudinal, and vertical directions. Now adding weight globally will affect handling around these axis, and if the added weight is not symmetrical the handling will be affected accordingly and can produce a more/fwd, in/out, up/down CG. So knowing approx where your CG is and weight and balance is critical to handling and control.
Sounds like you got a good car and are on the right track, removing overhead weight depending on how far it is from the CG will improve handling in those directions. When you lengthen your wheel base you do add additional stress to the chassis because the distance to the input load(tires) to the CG has increased. The chassis will fatigue faster depending on the amount and affect reliability. That is called a bending moment equal to the load at the tire(s) times the distance (arm) to the CG. The less weight you can put at large distances away from the CG means less chassis stress & fatigue, better handing and shock reactions.
Depending on exactly what your issues are above 75 mph will determine where you add your weight and arm. It may turn into a balancing act in both lateral and longitudinal directions to gain both high and low speed handling, and as a last resort changing the axis of your suspension if that is allowed in your rule book.
Hope that makes sense not easy trying to simplify a complicated task.
Hard to compare any car to another there are so many variables that affect handling.
If one were to take a ball and call it a CG it is easy to move in any direction. Now position it in four tires, centered then the handling is symmetrical around the CG axis, lateral, longitudinal, and vertical directions. Now adding weight globally will affect handling around these axis, and if the added weight is not symmetrical the handling will be affected accordingly and can produce a more/fwd, in/out, up/down CG. So knowing approx where your CG is and weight and balance is critical to handling and control.
Sounds like you got a good car and are on the right track, removing overhead weight depending on how far it is from the CG will improve handling in those directions. When you lengthen your wheel base you do add additional stress to the chassis because the distance to the input load(tires) to the CG has increased. The chassis will fatigue faster depending on the amount and affect reliability. That is called a bending moment equal to the load at the tire(s) times the distance (arm) to the CG. The less weight you can put at large distances away from the CG means less chassis stress & fatigue, better handing and shock reactions.
Depending on exactly what your issues are above 75 mph will determine where you add your weight and arm. It may turn into a balancing act in both lateral and longitudinal directions to gain both high and low speed handling, and as a last resort changing the axis of your suspension if that is allowed in your rule book.
Hope that makes sense not easy trying to simplify a complicated task.
Last edited:
