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Old 11-19-2007, 04:24 AM   #1
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Default Wonder whats wrong??

Just had my first race last week... it was a carpet stock class race. had heaps of fun and loved the adrenaline.. came last and was overlapped by the first car but maintained distance from the 2nd placed car that was behind me ..

The track is temporary setup and it is only setuped every 2 weeks, so practice on this track is a problem. Therefore i have problem setting up my car and didnt really know what to change for my car.
i usually run on asphalt... and the car setting is alright for it but can still be very much improved.

One problem i always have is, my rear end is sliding a little on the carpet and after sliding, the car comes to a near halt and i lose alot of lap times due to that. i drive a real old corally C4.1 and i refuse to get a new car as i believe this car is good enough and its a good practice car... i doubt the problem lies with the car... maybe with the settings.

this is how i setup my car for carpet:
Droop: 6.5mm (front) and 8.5mm (rear)
Camber: -2 (front) and -2 (rear)
Ride height: 4.8mm (f) and 5.2mm (r)
Toe in: -1 (f) and 2 (r)
Springs: not sure of lbs but its white corally springs and i believe its medium weight springs both front and rear
Shock oil: front and rear 40wt
Shock hole: all open (4 holes)
FGR: 4.83
Roll out: 40.94
Front diff: medium
Rear diff: loose
One way bearing: very tight (should this be loose if i racing stock and dont use much break?)
track width: 190mm front and rear
Foam tires: 37 front and 30 rear (DTM foams)

Feelings about the car is that i feel that it's kinda sluggish, and hard to drive, it seems slower then other cars on the striaghts as well. i've asked for help from the shop owner... he said, pay attention to my line of drive (i know i need to practice heaps more), and it might have to do with my controller settings... he said to turn down the servos, slower rate and lesser steering throw. i know that will help, but my car is already understeer but yet sliding a little at the back. unfortunatly i couldnt get to practice much before and after the race... wonder what i should do next?
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Old 11-19-2007, 04:38 AM   #2
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Quote:
Originally Posted by bigbutstupid View Post
Just had my first race last week... it was a carpet stock class race. had heaps of fun and loved the adrenaline.. came last and was overlapped by the first car but maintained distance from the 2nd placed car that was behind me ..

The track is temporary setup and it is only setuped every 2 weeks, so practice on this track is a problem. Therefore i have problem setting up my car and didnt really know what to change for my car.
i usually run on asphalt... and the car setting is alright for it but can still be very much improved.

One problem i always have is, my rear end is sliding a little on the carpet and after sliding, the car comes to a near halt and i lose alot of lap times due to that. i drive a real old corally C4.1 and i refuse to get a new car as i believe this car is good enough and its a good practice car... i doubt the problem lies with the car... maybe with the settings.

this is how i setup my car for carpet:
Droop: 6.5mm (front) and 8.5mm (rear)
Camber: -2 (front) and -2 (rear)
Ride height: 4.8mm (f) and 5.2mm (r)
Toe in: -1 (f) and 2 (r)
Springs: not sure of lbs but its white corally springs and i believe its medium weight springs both front and rear
Shock oil: front and rear 40wt
Shock hole: all open (4 holes)
FGR: 4.83
Roll out: 40.94
Front diff: medium
Rear diff: loose
One way bearing: very tight (should this be loose if i racing stock and dont use much break?)
track width: 190mm front and rear
Foam tires: 37 front and 30 rear (DTM foams)

Feelings about the car is that i feel that it's kinda sluggish, and hard to drive, it seems slower then other cars on the striaghts as well. i've asked for help from the shop owner... he said, pay attention to my line of drive (i know i need to practice heaps more), and it might have to do with my controller settings... he said to turn down the servos, slower rate and lesser steering throw. i know that will help, but my car is already understeer but yet sliding a little at the back. unfortunatly i couldnt get to practice much before and after the race... wonder what i should do next?

For one, you're running too soft setup for foams.
go to 70 front 50 back.
stiffer spring front as opposed to the rear.
DON't run one-way with foam but diffs fr+rr and NO center one-way at all.
Use/experiment with your droop screws and try to keep low-profile rubber!
Lower the car to 4mm all around.

What body do you use?

The car, due to its older (masssive) desig might indeed BE a litlle sluggish/heavier compared with other mor current cars.


Hope this gets you on the road
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Old 11-19-2007, 04:45 AM   #3
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Since you have a old Corally car, call Corally USA and see if they have any old set-up sheets still hanging around.You'll probably find out that parts are hard to find for that car- but I know were one-two of them might be.It's also harder to drive that car on carpet that the RDX or PHI.If you're looking for a better carpet Corally car I've got a used RDX ready to go. But I'd call Corally USA and talk with them first.
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Old 11-19-2007, 04:51 AM   #4
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Well, unfortunately driving a really old car like that is a bit of a problem. Firstly it is several generations outdated in pure handling terms. Secondly it is going to be hard to share setups as you may well be the only person in the world competing with one. Thirdly parts will be an issue when you need them.

However, if you do want to stick with it (good for you I say), what you have described (rear looping around) sounds like a problem with the front end just being too soft essentially.

Try a stiffer front spring, this should be the basic way to solve the "hooking" problem.

Secondly, ideally you want to run a front diff and locked centre drive on carpet with foams. The one-way also contributes to the rear looping around off power.

Beyond that it gets very complex, which is why the new cars are a big benefit, they tend to work better anyway and have more recently updated setups.

Stiffening the front end will generate understeer. You say you already have understeer.

However for most new racers the understeer is being caused by going too fast into the corners. So try backing off a little earlier, kissing the apex and powering out. Slow-in-fast-out is the basic way of driving, it is much faster than fast-in-miss-the-apex-stop-steer-fast-out!

EDIT: while writing this post a few replies came in above which say more or less what I am but a bit more concise!
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Old 11-19-2007, 05:08 AM   #5
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Quote:
Originally Posted by sosidge View Post
Well, unfortunately driving a really old car like that is a bit of a problem. Firstly it is several generations outdated in pure handling terms. Secondly it is going to be hard to share setups as you may well be the only person in the world competing with one. Thirdly parts will be an issue when you need them.

However, if you do want to stick with it (good for you I say), what you have described (rear looping around) sounds like a problem with the front end just being too soft essentially.

Try a stiffer front spring, this should be the basic way to solve the "hooking" problem.

Secondly, ideally you want to run a front diff and locked centre drive on carpet with foams. The one-way also contributes to the rear looping around off power.

Beyond that it gets very complex, which is why the new cars are a big benefit, they tend to work better anyway and have more recently updated setups.

Stiffening the front end will generate understeer. You say you already have understeer.

However for most new racers the understeer is being caused by going too fast into the corners. So try backing off a little earlier, kissing the apex and powering out. Slow-in-fast-out is the basic way of driving, it is much faster than fast-in-miss-the-apex-stop-steer-fast-out!

EDIT: while writing this post a few replies came in above which say more or less what I am but a bit more concise!
Great minds think alike

Last edited by PizzaDude; 11-19-2007 at 05:24 AM.
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Old 11-19-2007, 07:04 AM   #6
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If you run into a parts problem, your Corally shared suspension parts with the Serpent Impulse. Also most of the parts are shared with the Xray T1 as it was almost a clone of this car. While it too is an older car you have another source to scrounge up parts.
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Old 11-19-2007, 08:11 AM   #7
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It sounds like you're describing a car that is "over rotating" in the corners. If you are entering a corner and at about the mid-way point the rear end "gives up grip" and slides out on you.. You have to much front end grip and not enough rear grip..

The trick is how to maintain that front end "good grip" while increasing the rear grip to better balance the car around the corners.

First off, you need to pick up the XXX Main set-up book, or the Hudy Set-Up book, both have a grid on chassis changes that help remedy certain handling characteristics.. Read both books and carry them with you in your tool box, while there not perfect, they sure get you in the ball park.

Second step, we need to slow the transition of the weight from the back of the car to the front in the corners.. Your ride height is set with the rear about .5mm higher than front, I'd make both equal front to back.. Then check your rear droop (or chassis rise).. Use the ride height gauge underneath the back of the car, your ride height should now read 4.8 (just like the front).. Use a screwdriver underneath the chassis and lift the back of the car up until the tires just lift off the ground and then re measure the distance with the ride height gauge. The distance from the ground to the where the chassis just lifts the rear tires.

The difference in your ride height (4.8mm) and where the rear tires lift of the ground (lets say for example is 7.0mm) is (4.8mm ride height - 7.0mm tires lift) = 2.2mm of chassis rise.. As you decrease how much the rear of the chassis rises, you can decrease how much weight is transferred forward, which will reduce front grip and increase rear grip in a corner.

Chassis rise or droop is a fairly easily change at the track and can make a big difference.. Try a big change during practice, if you have like 3mm of lift, reset the droop so you only have 1mm of lift, go out and practice, if it's better great, if not, then go back to 3mm and will work on something else like stiffer front springs and softer rear springs.

Half the fun is learning how to go faster!
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Old 11-19-2007, 08:25 AM   #8
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Understanding how different settings on the car change the cars handling charactaristics is a good way of getting the car setup the way you like it.

The link below can tell you a fair bit about setup

http://home.scarlet.be/~be067749/58/tc/print.htm

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Old 11-19-2007, 08:47 AM   #9
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Old 11-19-2007, 12:27 PM   #10
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Quote:
Originally Posted by Impulse_racer View Post
If you run into a parts problem, your Corally shared suspension parts with the Serpent Impulse. Also most of the parts are shared with the Xray T1 as it was almost a clone of this car. While it too is an older car you have another source to scrounge up parts.
I do have a serpent impusle which has the same parts. since that gas car is of no use anymore, im currently using it as spare parts... up til now, i have no break any parts yet... its kinda strong based on how badly the car flips at time

anyway, thanks guys for the reply. i will try some small little changes at the time when im at the track in 2 weeks time... ill try to let u guys know how i go.

Last edited by bigbutstupid; 11-19-2007 at 12:38 PM.
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Old 11-19-2007, 01:46 PM   #11
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Your rollout could also be the cause of your sluggishness. What in the world motor are you running a 40.94mm Rollout with? If it's a CO27 try going down to a 27-29....that may help in that department.
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Old 11-20-2007, 02:42 AM   #12
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Originally Posted by Glowster21 View Post
Your rollout could also be the cause of your sluggishness. What in the world motor are you running a 40.94mm Rollout with? If it's a CO27 try going down to a 27-29....that may help in that department.
just a johnson 540 silver can. It was the shop owner who helped me work out the gearing as it's my first time racing.. i believe its right as stock race should have approx rollout about 38-40??
however, i notice that the motor runs really really hot. cant touch for even a second. even my 19t doesnt run that hot on the same car.. so i believe its not the car that is causing any drag. the 19t motor, i run with FGR:7
anyway.. gonna get some springs tmr and test it on a asphalt track...
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Old 11-20-2007, 03:28 AM   #13
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The way you use your throtlle as well as the lines you run ontrack can really make a huge difference with regards to the sluggishness.
People allways underestmate this a lot.
Because it does look like one or the other is way faster, people allways "blame" the motor for being stupid fast.
Or in your case, yours being slow.

It being really hot is NOT a good sign.
Is there a way for you to borrow and test another 27t motor?

Good luck.
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