if u change the lower,does not affect the upper linkage,only the lower arm angle change..

try this theory,like a handrail left and right walkway,if u lift ur shoulder and make ur arm lower,if u try to go side way its gona b bit hard,so it is less rolling..try to lower ur shoulder and make arm higher,then u l have ur body roll a bit..

Cuz the roll center is at the lowest point using A.

i don't get you guys. ever since the mtx3 people get the roll centres wrong!!

A is for high traction tracks when grip is abundant and not needed.

C is for slippery conditions.

C places the weight of the car higher up, and places the arms angling down to the ground. this creates a greater force pushing the point of the arms (the wheels) into the ground, hence more grip!)

A blocks make the arms paralel, and in most case angle up, this places less pressure on the end of the arms (the wheels) and causes the car to slip.

C blocks make the car more rear end taily due to the beter grip, some of you guys might be mistaking this for sliperyness

obviously you guys never race on a proper high speed high grip track just cuz someone posts on this MTX4 forum all the time doesn;t mean they know more or less, but just don't take their word as gospel because you see their name all the time

Sorry Jay and VWO, i agree with this dude 100%. You guys are confusing roll centre with centre of gravity! A roll centre is a theoretical point around which the chassis rolls. The amount that a chassis rolls depends on the roll axis relative to the cars centre of gravity (C of G). The closer the roll axis is to the centre of gravity, the less it will roll. The further away it is from the C of G, the more the car will roll. This works on the simple principle of mechanical advantage, and moment arms .. It's lika a lever. For the sake of this excercise, lets treat a Bolt as our (C of G), and the handle of our lever as the roll centre. If you had a lever with a short handle, it will be more difficult to untighten the bolt than if you had a lever with a long handle.

The Roll centre sits below the centre of gravity on cars, hence they roll whilst cornering. This is the opposite to Motorbikes. A Motorbike's Roll centre is above the C of G, and thats why they tip into corners.

In conclusion, the greater the distance between the C of G and the roll centre on the Mugens happens to be the "A block". Hence, this would cause the most body roll (traction). The shortest distance between the C of G and the roll centre is the "C Block" and this will allow the least body roll..

NJ

Sorry but i agree with VWO and Jay and ACM, read back a couple of pages and you will see a really good explanation....or was that on the MTX-3 forum not sure but what they are saying is correct

take note ,that roll center is also effected by ride height and tire size .

rody, dude, when we race and moorebank and when they used to VHT the track, back in the days mbank had stupid amounts of grip and people traction rolled we would put the A block on the rear as this made the cars rear end slide and reduce traction rolling.

if we put a C block in the 3 in these conditions the rear end would squish around and would be too grippy to the point it would snake around and sort of act weird, not loose grip , but infact have too much front end steering due to the rear also steering.

people can argue all they want, i know what works on my track.

you don't use A blocks at tempe do you? i'd use a B or a C there with a C steering block. (C steering gives better exit, and i'd compensate loss of entry with a softer tyre).


AY I GOT MY MONO PARTS!! all i need to do is get the lithium ion batt and the capacitor for the craptrum and i'm ready to kick your but jay and rody!!

I cant believe no one mentioned droop to this guy as a major tuning aid.................

Hi,

There are 2 things that can be checked for the scratch ring on the 2 speed housing.

1) Rear sway bar touching, when car is lifted up - Caused by too high rear droop.

2) When installing back the engine with the engine mount and screwing it back to the chassis, you need to "angle" out a bit on the 2nd Gear, thus having the maximum allowable clearance between the clutch bell and the 2 speed housing. ( From my experience... )

Hope this helps ...

Happy Racing !

Thank you....

I did mention droop.

I'm sure grinder has his own droop ( he said stock setup ) and I know Scott mentioned about it.

Read again his problem :

" The car had a bad off power push, and slightly loose on power " ---> my suggestion try 400 or 450 wt.

" When I tried to push the car on power it breaks loose. I think this is mostly due to low traction. " ---> my suggestion lowest hole on inboard camber link and add 2mm shims on rear uprights. ( He said he use none and put it in middle hole ).

I don't understand what this is : front pins all the way down

Does he mean caster ?

Please offer an educated explaination. Try not to defy physics when you do it.

I think 6 years of flying as well as 10 years of racing 1:1 cars entitles me to a little bit of understanding about roll centres. Im not twisting anybody's arm to believe what i wrote but when VWO comes over my place and i show him writing he will change his mind! . If anybody has the XRAY T2, look at the set-up guide on page 24. Also, look at the XXX main set-up book.

p.s. VWO, we are not talking about what works at moorebank, we are talking about roll centres.

p.s.s I do use the A block at tempe!

In future i will stay out of this debate as obviously there are alot of opinions out there on this topic and i have only been racing 12 months and dont have enough expirience. I was only going on what i had been told before on the MTX-3 thread and after putting into practise what was said there it worked and that was "C" Blocks have the most traction and "A" blocks the least and after seeing what setup's guys had that ran on high traction tracks versus low traction tracks, it seems that the faster guys in Australia use the B and C blocks for med to low traction tracks and the A block for higher tracton tracks.
So in conclusion i am sorry if i upset anyone on here but i think in future people who are asking the question on this topic should just do some research for themselves to save the differences of opinion and the arguments.

Cheers Dan

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