got your suspension sorted???

[greyghost]

here is a clip of the Baja 1000 winning trophy truck testing its suspension



very impressive around the 2.40 minute mark

[christover1]

coooooool

[gwagensteve]

http://www.youtube.com/watch?v=g8GtaGdp9ww

And here's the difference between IFS and live axle. Watch the difference between the first three cars. The second car is IFS.

This is the best explanation why 4WD's are moving away from live axles - it's all about the unsprung weight.

Steve.

[mightymouse]

http://www.youtube.com/watch?v=g8GtaGdp9ww

And here's the difference between IFS and live axle. Watch the difference between the first three cars. The second car is IFS.

This is the best explanation why 4WD's are moving away from live axles - it's all about the unsprung weight.

Steve.

i understand your logic Steve, but IMO unsprung weight is an outcome not the reason. Take the whole thing back a layer and its
about the driving characteristics being more important to the MAJORITY of users than what we would consider "off road" capability. Live axles bring a whole bundle of advantages and disadvantages - its the "fit" to the purpose that controls their application

I like independent suspension...... if its designed with the expected purpose in mind its very effective but in so many cases the "expected outcome" is 99% bitumen and 1% road - so common designs ( i.e. things we buy from an OE ) are optimized - they do one thing well and the other....... not so well.

Vits are classic examples..... ride well for a short vehicle and not unpleasant for moderately big distances. Surprisingle capable for what looks like a shopping vehicle BUT its essentially road based IFS's design creates issues that are significant for some styles of 4WDing.

[gwagensteve]

I'm not sure it's merely an outcome.

The high unsprung weight of a live axle and the compromises of link design when used in the front will result in poorer ride and handling than is possible with a live axle. Manufacturers are looking for the best fit for use, and that places handling at speed above low speed capability. IMHO the biggest impediment to a live axle handling at speed is unsprung weight, and that video shows its effects with "the tail wagging the dog"

Sure, some live axles ride well and some IFS cars ride poorly, but for a number of reasons, but mostly centered around unsprung weight, it's not possible to achieve the ride and handling of an IFS car with a live axle.

Those KOH cars provide an excellent demonstration of the difference, even when tuned for a very narrow operating range. (i.e high speed offroad handling only)

Steve.

[mightymouse]

I think we have ended up saying the same thing.....from different ends of the logic chain.

I'm suggesting from a design perspective......

EXPECTED USE controls RIDE/HANDELING EXPECTATION controls SUSPENSION DESIGN controls UNSPRUNG MASS...... if you follow.