Weight distribution test on CR2

[Northy]

I mean everyone.....

G

[Legacy555]

Would you agree that the weight distribution on a B4 with an old sub C cell arrangement is pretty close to correct?

[Chris Doughty]

also to remember just a weight distribution number such as 35/65 can be achieved in many different ways resulting in different polar moments.

2 cars, both with a 35/65 distribution can be so different if one has its mass spread along the chassis (stick Lipo cougar style) and one has its mass spread across the chassis (x6 stick Lipo style)

[Northy]

Originally Posted by Legacy555

Would you agree that the weight distribution on a B4 with an old sub C cell arrangement is pretty close to correct?

I have no idea, the car has been successful though......

G

[Gayo]

I weighted my brand-new CR2 (). Weight balance seems good with 64% on the rear but overall my car weights only 1570g.

Do you think that I should add weight to match others' cars with 1650-1700g overall, or is it weight ratio that matters?

I know I'd better try it by myself but I'd like to have oOplers' opinion on this.

[Legacy555]

I would suggest that it was fairly close to being spot on, so perhaps no actual "learning" is required, just an adaption of existing dynamics.

Your average club racer will trial and error his (or her) way with all sorts of addition weighting and compensation all over the chassis till a neutral point is found, but no self respecting engineer would - you have to go mathematical - that's where manufacturers come in.

A car weighted up ~200g over minimum will have more polar inertia, will pitch and roll more and will require more traction effort from the tyres to get the whole car moving. Doesn't add up to me....... just my thoughts.

[Chris Doughty]

the reason the heavier cars are prefered is that everything reacts slower with a heavy car, you can be a little off with the setup, you don't have to catch it as fast.

a properly setup car on the weight limit will be quicker, have more grip, change direction faster and with a driver who is 'fully on it' will be quicker.

but would it be quicker to do a run with this light car with a crash/marshall versus a 'safe' car with a clean run... I guess thats up to the driver to decide

[Legacy555]

Originally Posted by DoughtyUK.net

the reason the heavier cars are prefered is that everything reacts slower with a heavy car, you can be a little off with the setup, you don't have to catch it as fast.

a properly setup car on the weight limit will be quicker, have more grip, change direction faster and with a driver who is 'fully on it' will be quicker.

but would it be quicker to do a run with this light car with a crash/marshall versus a 'safe' car with a clean run... I guess thats up to the driver to decide

That's a good point, well put!

Would be an intersting study to find out the difference in performance between a weighted and unweighted car with same driver. Including time lost for driving errors

[Chris Doughty]

I'd be interested to see that too.

and the reason it appears to be a 'new' fad of weighting up cars is that now we are hidiously overpowered we don't need to save weight to make the 5 minute run.

back in the day when we ran 1600 cells and 15 turn motors any extra weight on the car would mean you might not make the run-time, plus the cars were dog slow in comparison to today.

[Gayo]

Thanks guys. I am going to do a 50-70g lead plate that I will put under the lipos, right where the CG is, so I can check quickly which weight setup is better for me.

[tony12795]

Just to keep you guys in the picture, the team are now running and testing aluminium chassis. So the CF is around 95g and the aluminium is 190g. Danny and Si will confirm this.

I was testing over it over the weekend and found the car even better on high grip tracks.

There laser cut and the quality is first class as you would expect from AC!!!

The only weight I was using was at the front under the servo to keep the high speed steering.

Tony

[Reevsey]

Originally Posted by tony12795

So the CF is around 95g and the aluminium is 190g. Danny and Si will confirm this.
Tony

My chassis is 80g heavier than standard

[Danny McGee]

Originally Posted by Reevsey

My chassis is 80g heavier than standard

Mines 192.

The new one that im working on will be about 240 and will eventually look ace

We will keep you posted

[tony12795]

Hi Danny, I have heard about your new chassis. When's it going to be ready??

[Gayo]

Originally Posted by Danny McGee

The new one that im working on will be about 240 and will eventually look ace

Is it made of gold?

[Danny McGee]

Originally Posted by Gayo

Is it made of gold?

I was actually thinking of a mix between Frankincense, Myrrh and Gold. Only issue with that is, it wont be heavy enough

No idea when i will have one done. Sorry, im busy with work and its going to take me a day probably to get it all done.

I'll let you see when its done