"probably the same reason all off-road vehicles mount their shocks with the shock shafts pointing downward."

has to do more with a Sprung/Unsprung weight issue and the adverse affects on handling it would cause by having the a-arms bear the weight of shocks and do dampening. now i have seen guys mounting shocks backwards on offroad cars converted to run oval...lowers CG is the reason they give.

Sorry, you've lost me. If the shock is upside down then the bubble would be in the oil chamber of the shock, and would rise to what would be the "bottom" of the shock normally. If the shock is right side up the bubble is still in the oil chamber but would rise to the end with the seals.

Oh this is so confusing! Will "upside down" become "rightside up"? :lol:

G Ace: I was looking at the number of holes in the chassis and the closeness to the edges and each other. Less material equals less strength, increases the chances of breakage. The tweak plates each use 2 standoffs. Frank has modified battery o-ring posts on this car.



I agree on the shock piston in the oil but have to add to this that this installation adds unsprung weight to the rear suspension.



The Capacitor on the ESC acts as a buffer to help keep the supply battery voltage up above the BEC voltage under short high amp loads. In the stock classes where the motors do not draw the high amps like the low turn modifieds, a cap is not needed. The cap is easier to install and use than a receiver battery pack.

My head hurts.... :confused: :confused: :confused: :confused:

-James

That car is pretty similar to the one I made to upgrade the Carpet Knife. I put the tweak holes in too, and extended the rear pod like the 12l4.

Thanks for the info guys. As mentioned, from my offroad racing I was concerned with the sprung vs. unsprung weight of moving the whole shock body vs. just the piston. Probably with the size of a 12th scale shock it's not as much of a concern.

Bear with me here. The oil chamber is the same size and the movement of the piston is the same regardless of which way the shock is mounted. So if there were an air bubble at the top of the chamber, my thought would be the piston would hit it regardless of which end was which. Considering the shock is more laid down than upright, the bubble would be more on the edge and not near the shock shaft. Maybe it has to do with the relative starting position of the piston. I’m not questioning anyone's information, just trying to understand what's happening as I'm looking at my car. I'd be curious to know if during the movement of the pod during a race, whether the piston is more at the bottom or the top of the oil chamber.

I guess the secret is to build my shocks without any air bubbles so I don't have to worry about it.

My head hurts....

brushless setups!
 

I am starrting to see alot of brushless setups in the 1/12th world but i dont know what the big deal is?Whats the diffrence between brush and brushless? does brushless give you an advantage?

Mine too. I'm going to mount my shock sideways. :p

Do you need the cap with the GTX when running 4 cell stock?

With brushed motors you have to remove the motor, cut the commutator and install new brushed every run to keep it fast (At least around here you do :rolleyes: ).

With brushless you instal your motor and you forget about it. Every few months you take it out clean the bearings, oil them and put the motor back in. Brushess motors are about 10-20% more efficient than Brushed motors. This means run time is a lot less of an issue. The Mod 1/12th brushless guys are running full punch for 8 min with no worries about run time at all.

Brushless costs about $100-150 more than brushed systems but thats about 6 months of motor brushes if you race a lot.

I'll give the shock explanation a try.....

The shock on these cars is run very close to max extension at all times. Or "topped out". This is the key point......

If you run the body of the shock attached to the pod ("upside down"), the oil reservoir is the highest point. The shock piston is nearer to the lower end of the shock. Air bubbles will rise to the highest point. Which is the opposite end of the piston. So the piston will always be in oil.

If the shock is "right side up", and there is air in the shock, the piston will be in the air bubble, and move very freely for the first bit until the piston hits oil.

I'd rather have consistent shock action over lowering the unsprung weight a gram or two...but that's just me. Well, I'm lazy also, and can go a few more weeks without rebuilding the shock this way.......

Just last weekend a very experienced oval racer asked me why my shock was "upside down".......I told him about the air bubble, and he just looked at me like a deer in the headlights.......

Early 3.2 Prototype info!!
 

I spoke with Frank today about setting up my t-fource and my 3.2r abp and I got some cool insights on the early prototype that Mcmahon won the National Championshp and also 2nd an 3rd.

Frank said the Knife pictured from the Nationals is a early prototype. The car is more narrow, stiffer and lighter than previous cars. Then unlike other link cars on the market, the car uses either tape or an o-ring to hold the cells. The combination of the two-piece tweak plates and the newly designed graphite O-ring hooks make for a new O-rings battery retention system that is at an all time high for pack secure ness and positive mounting. The new system cradles the cells, keeping them in place. The new O-ring hooks eliminate any chance of the O-ring coming off. It's dialed, throw away the tape.

I hate tape. Anyways-I hope this doesnt land in the "already know that" category. Also-the tweak system as you all noticed is revised and a large part of that was to stiffen up the tweak system and allow for that trick battery retention system.
Ask away if you have mre questions n it-except when it will be available. :)

Ray

Thanks Manning, that makes sense. That was the piece of information I was missing.

That's the other thing... the normal travel of a pan car shock is 1-2mm at the most, the piston is never moving through the majority of the shock body (like an offroad shock). So if there is an air bubble in the opposite end of the shock, the piston is never coming anywhere close to it anyway.

Manning, I learned a long time ago not to try and reason with an oval guy. It's like trying to reason with a mountain lion, or a fundamentalist Muslim, or a Republican or something... :lol:

Hey, I'm an oval guy ... And I always thought I've been easy to get a long with, easy to reason with ... I like talking r/c cars, no matter what style or kind ... I keep an open mind about new ideas .... Even those we ideas we steal from slow on-road cars! LOL :)