joamu

Thanks - that is helping.

Regarding the roll centre - I have learned from this forum that this car especially is setup through the roll centre at least there has been a lot of posts around the correct roll centre here.

From your experience - do you often have to change the roll-centre according to the race-track or would you rather prefer to change the geometry?

From what I have seen on this forum so far, I intend to lower the diffs, drill the front holes - leave the riser bars and add 1mm in front as well as 1,5 to 2 mm in the rear.

What would you think?

aus jd 2703

iTrader: (5)

what does changing the camber links affect??
looking to settle the rear end down as it gets a bit loose on cold tires and is still slightly loose when up to temp can camber links help this also how do u get more steering through a sweeping on power bend? thanks all

axxis-boy#1

i am planning on bistin the carpet car back out in the next few weeks. i know i had my car dialed last year, regularly beating jeff cufs and jason schrefler at horsham rc. but i threw out my setup. what is the starting point as far as springs and shock oil? also, what wheelbase should i run?

Nexus

iTrader: (42)

Forget the Pit Dude...

I just order my new Pit Goat!

wallstreet

iTrader: (24)

I love it and the goat


Viva Las G.O.A.T. !!!!!!!!!!!!!!!!!!!!!!!!!!!!

Jon Kerr

iTrader: (17)

Roll center effects how the car rolls. It stiffens or softens the car through the geometry of the camber links relative to the lower suspension arms. Generally a lower roll center will roll more and give more grip on that end of the car. A higher roll center will be more stiff and will usually generate less grip. You can get a lower roll center a number of ways. You can lower the suspension arms by lowering the pivot blocks, (this is what we're doing when we say we're lowering or raising the roll center or on the setup sheets the roll center field is amount of space between the pivot block and the chassis.) or you can raise the inner camber link, lower the outer camber link, or lengthen the camber link. All of these adjustments will effectively lower the roll center. Doing the opposite will raise the roll center. But they all will work slightly different. I personally prefer to adjust the suspension arm height when adjusting roll centers. Camber link changes always feel like they're huge changes where raising or lowering the suspension arms .5mm is a little more subtle.

I've found I like the front roll center at about 2mm (just the riser plate under the pivot blocks) and the rear at 2.5mm-3mm. If there rear is too stuck you can raise it up a little or raise the outer camber link on the rear hub. Do this .5mm at a time because it can make a huge difference. You want to get the roll of the car balanced too. You don't want more than about a 1mm split between the front and rear roll centers. If the front is rolling a lot more than the rear, it's going be really inconsistent and hard to drive.

Go HERE to get a really good explanation of roll centers with animated pictures. This site has a lot of good information on it. It's geared more toward off road but most of the suspension section applies to on road as well.

joamu

perfect explanation, thanks

aus jd 2703

iTrader: (5)

thanks jon would changing the roll centre affect a sweeping bend?
and which would i make more time up in a single very high speed chicane or 2 medium high speed sweepers both leading onto a straight? just deciding whether to get more on or off power steering i think more on power wil help overall but cant decide lol

Jon Kerr

iTrader: (17)

Anytime. Glad to see you're liking the EC. Anytime you need help, ask away. There's always any number of team drivers in here who can help you out.

Jon Kerr

iTrader: (17)

To gain more on power steering I'd take out a little front droop. Through the chicane, is the car just too sluggish or is it not steering?

seaball

iTrader: (9)

that's just damn beautiful.

aus jd 2703

iTrader: (5)

ok im running 2mm front and rear droop and i drop about 1mm out rear to get rid of a loose rear end in the final so ended 2mm front 1mm rear is this normal?
battery in forward position rear diff loose front diff normal rear shocks as per kit except stood all the way up front standard except with new schuie white springs and blues on rear .5 toe out 2.5 in rear 4' caster does this all seem normal???
for next meet i might raise the rear hubs by .5mm to give mor weight transfer under brakes and as u said run less front droop.
does this all sound right??

Jon Kerr

iTrader: (17)

I'd say you're not running enough rear droop for sure. That little droop won't allow any weight to transfer to the front. Go to 3mm of rear droop, and put a spool in the car. A diff is going to hurt the car in pretty much every way. What's happening on power through the sweeper where you can't hold it flat out where others can is the inside of the car is getting light as you go through the sweeper and the front end is "diffing out" or unloading. This will make the front end push badly, then possibly make the back end break loose suddenly as the weight shifts.

rcshark

hello from irac. didnt bring my ride with me looking for a new se kit to build or should i waight closer to the new year?

aus jd 2703

iTrader: (5)

ok dont have the money for a spool let alone new drive shafts so is it reversable to 'Llock' the front diff using card board and no diff balls??