mr4-bc or works 93 runner?

[stickboy007]

Ok, fair enough, but my point remains. If you start with the same 4wd platform, at what point can you call something a "pure" off-road or on-road design?

[aip47-2008]

you are completely backwards on the assumption, actually. The 870C is the early evolution TOWARDS the typical belt drive touring car. Not the other way around. the yr4 was born out of taking the 870c and making the chassis narrow to become 'correctly' scaled to 1/10 sedan bodies.

Backwards indeed!!!!

[stickboy007]

Anybody care to answer my question? How do you define a "true" off-road design or a "true" on-road design if the platform is the same? A true off-road design is a very broad term, and the design itself depends on the surface you are running on. The 870 was apparently an off-road design, but it jumped like garbage...

[aip47-2008]

I had no problems jumping mine BID.

[stickboy007]

I would challenge you to try it on a modern track. Older tracks didn't have jumps. They had bumps

[Coelacanth]

I would challenge you to try it on a modern track. Older tracks didn't have jumps. They had bumps

Modern tracks aren't for cars; they're for people who want to fly but can't handle a radio with more than 2 channels.

[stickboy007]

Still way more technical than old tracks which are just dug out of a backyard

[jwscab]

look at the chassis development and drastic difference between a real on-road pan car with 1/4" (or less) total suspension DEFLECTION vs an off road buggy with fully articulated arms with 1" (or more) suspension travel. If you were to compare that to 1:1 scale, that's 3" of suspension travel you might find on a ferrari or corvette vs a foot or more travel in something like a baja racing truck designed to jump over dunes and through gullies.

bottom line is it was easy to take a 4wd chassis and adjust the width to suit the 'true' 1/10 scale proportions.

there are certain design elements that are different in off road vs on road like:

scrub angles and ackermann
front end caster and front end kickup
caster and camber gains(shorter travel, you need a different gain curve)
rear toe in
chassis weight balance

and then of course, one other item certainly affected the evolution of the yz10, and that would be durability. Much of the yz10 development and refinement was in suspension robustness.

[stickboy007]

I would agree with that. Now, the original claim that started this as that the MR4BC was based on a touring car while the YZ10 is a "true" or "pure" off-road design. I would argue that the origin is less important than the actual performance, and furthermore that they each have off-road design elements. An MR4BC should be vastly more competent on an offroad track, especially a modern one where you spend about as much time in the air as on the ground. If you took a B44 and made it rear motor with belt drive, it would look a lot like a MR4BC.

[Coelacanth]

I would argue that the origin is less important than the actual performance, and furthermore that they each have off-road design elements.

This is what I'd use to define whether a car was "offroad" or "onroad". Does it perform in its primary function, be it offroad or onroad, effectively & logically? If so, it can be classified as such. Lots of people, and companies, made half-assed attempts at converting existing RC chassis' from offroad to onroad to monster truck or whatever, with varying degrees of success. But if a converted car cannot perform its new function effectively, it can't really be classified as such.

I would also suggest that a car's "true" function would be the one it does best. If you took an onroad chassis and did a lacklustre offroad conversion to it, and yet it still drives better onroad than offroad, it can't truly be classified as an offroader.

Just my opinion. I felt compelled to share it because I did just that with my CYANide build, converting an offroad chassis into a touring car chassis. At first, I had the silly idea that the chassis could easily do both, but the more I delved into making that chassis work properly as an onroad car, the more I realized what was involved in making it actually WORK that way. Narrowing control arms & track, fabricating custom shock towers & bumper, tweaking ride height, adjusting body height on the chassis, re-thinking the pinion & gear ratio & rollout due to the use of smaller-diameter tires, and a lot more had to be done to make it actually perform as an onroad car. I learned that there's a great deal more to doing a mod like that than merely slapping on a few onroad body mounts, non-spike tires, and calling it done. Once I got that far down that path, I knew there was no going back to offroad with that particular car.

[Lonestar]

I felt compelled to share it because I did just that with my CYANide build

[Lonestar]

jwscab ha explained it all nice and clear...suspension geometry (including roll centers and by consequence bulkheads design), low CG, mass reparttion, these are the key to make an onroad car... result must be very very different from offroad, no shelf engineering here.

if you guys race modern DTM EP, you know onroad has grown even further apart from offroad now... it'd be impossible to do a platform that does both with excellence. manufacturers arent even trying any more

lets look at it differently then - mr4bc is plasticky, yz10 is SEXY that seals it all

paul

[stickboy007]

Now that that is settled, I think there's a broader point to consider here, as far as "design" goes - does it put a smile on your face? It could be a poor design and a pile of dogmeat either on road or off road, like oh, say, a Lunchbox (no offense, Lonestar), but if it's hella fun to drive, like oh, say, a Lunchbox, then it has precisely the right design.

That the MR4BC is newer, or rather, less old, than the YZ10, should make it a better runner in terms of parts availability (maybe?). I love the YZ10. I drool over mine every day, but some parts are not easy to come by and so when I eventually do take one on the track, I expect I'll drive it with some sense of fear, despite its robust design. Break an MR4BC, and nobody really cares, but every time you break a YZ10, God kills a kitten.

[Lonestar]

Now that that is settled, I think there's a broader point to consider here, as far as "design" goes - does it put a smile on your face? It could be a poor design and a pile of dogmeat either on road or off road, like oh, say, a Lunchbox (no offense, Lonestar), but if it's hella fun to drive, like oh, say, a Lunchbox, then it has precisely the right design.

I unfortunately cannot disagree with you in any way on this

That the MR4BC is newer, or rather, less old, than the YZ10, should make it a better runner in terms of parts availability (maybe?). I love the YZ10. I drool over mine every day, but some parts are not easy to come by and so when I eventually do take one on the track, I expect I'll drive it with some sense of fear, despite its robust design. Break an MR4BC, and nobody really cares, but every time you break a YZ10, God kills a kitten.

agree again

Run whatever makes you happy anyway, whether it's behind performance, design, or parts availability!

Paul

(PS - I still mourn after my long-sold and highly modded VLB, which, granted, was handling like a pile of crap! Fortunately I still have a couple of nib gold editions in the attic somewhere )

[ericsp2]

I have spares for the works and am having Klien arms made for it and will run those but i think it should compete fine.
Its not heavy at all and has a slipper and one way diff