Wheel base and ride height?

SpeedRacer

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I notice that 120" to 125" WB is very common in deZert race vehicles - Jimco unlimited buggy, Protruck, Ragland TT. What makes this length so popular? It seems to me that a longer WB might be more stable in the sand washes and whoops while the shorter WB will turn better. Is 120" to 125" WB an experienced based compromise or is there more to it?

Also, is there a common definition for "ride height"?
 

FABRICATOR

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There is quite a bit to it. It has to do with overall weight, weight distribution, and placement of the weight. Also the type and capability of the suspension front and rear. As mentioned before, Walker Evans had a truck or two with extremely short WB and they were pretty damn fast. I think it was Bunderson who built some cars at least 130" and they worked well too. What is right for one is not necessarily right for another. You might consider this as a practical limit just like motorcycles and road race vehicles. The limit is brought about by several factors such as vehicle width and weight, power limits, wheel size and weight, fuel consumption, drivetrain limits, etc. There is the constant battle of sprung vs. unsprung weight. All of these must be considered. Longer WB would handle the bumps better but would turn like du-du, and weigh more. Then you start down the road of more power, stronger drive trains, all wheel drive, etc, etc, and reliability becomes an issue (sound familiar?). Practical size limits have been achieved in all forms of racing. This is not just because of the rules either. There is a level of efficiency that is reached. A much larger vehicle would require a tremendous amount of money AND proper designing. A bigger heavier beast generally does not like to fly, turn in the rough, or accelerate quickly, but it must to win any races.

<font color=orange>The best ideas are the ones that look obvious to the casual observer.</font color=orange>
 

Jack

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Speaking of size relations, it used to be that monster trucks could only slowly crawl over cars and do limmited jumping or risk a big brake, but that has changed, I would love to see somthing like the Tom Meets truck "Goldberg" out in the desert to see how it worked.

Has any body tried somthing so big in the dez?
 

ntsqd

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DAF did. Paris to Dakar. Two 500 HP diesels, one drove the front axle, one drove the rear axle. They weren't the only ones to do something huge. Seems the chase trucks were getting into some unofficial racing and the promoters decided to offer a 'chase truck' class.
DAF's entries were discontinued when in the middle of the race their truck hit a smooth ramp in the African desert at something outrageous like 120 mph + (this was a truck nearly KW/Pete/Mack etc. in size). At that point they were gaining on a Peugot 205 Rally car that I guess lacked sufficient tire footprint for the sand. Quite impressive. The problem was that the ground fell away gradually beyond the jump. The 205 made a beautifull jump off of it. The DAF noseplanted, as in a cab forward design that impacted with the front of the cab nearly flat to the ground. Enslow's Crusty Demons sand dune wreck stupidity was very neat and tidy in comparison. Several hundred feet of 'yardsale.' I think all three aboard were killed and I know DAF withdrew from competition immediately and to my knowlege has not returned.

TS

"Teach you all I know and you're still stupid"
-- Howdy Lee
 
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