NIRC. Chit Chat

[thzero]

Originally Posted by johnnyh66

no shit, turning sucked... when I was crying about it on Sunday, I think Hoopty said to much negative camber in the rear hurts turning radius.

I gave up on using the steering to get around the corners and relied on brake/throttle input.

Kinda have to do both... at least the few times that I felt I did some of the corners really well, I was using both to do it.

I think the most frustrating thing for me is the either throttle or brake. I'm used to racing with left foot brake, right foot throttle and being able to blend them together.

But yeah I think that is a part of the way the suspension is built for the Slash. I had to really dial back my EPAs to about 70% because otherwise it was hitting the limit and torquing the chassis which broke a few servo horns.

[badhoopty]

Originally Posted by johnnyh66

no shit, turning sucked... when I was crying about it on Sunday, I think Hoopty said to much negative camber in the rear hurts turning radius.

rear toe, not camber.

the more rear toe you have the better it will hook up and track straight on throttle, but less turning.

i would try flopping the rear carriers, iirc in the traxxas book that stock setup is 3°, flopped is 1°. this is with the alloys platinum carriers. the plastic carriers have a different toe-in that i forget.

you coulds also could try toe-ing out the front a little. in either case you will get more steering but it will get squirlier on power out of the turns and down the straights.

i'm gonna email the guy i bought my slash from and see if he knows what he used for diff oils. i had no complaints at all with how mine was hooking up, i just want fresh oil in it.

[johnnyh66]

I'd like more braking power...

[badhoopty]

copied and pasted:

Front Toe "IN"
Slower steering response
More straight-line stability
Too much will casuse greater wear at the outboard edges of the tires

Front Zero Toe
Medium steering response
Minimum power loss
Minimum tire wear

Front Toe "OUT"
Quicker steering response
Less straight-line stability
Too much will cause greater wear at the inboard edges of the tires

Less Rear Toe "IN"
Less straight-line stability
Less traction out of the corner
More steering
Higher top speed

Intermediate Rear Toe "IN"
Intermediate straight-line stability
Intermediate traction out of the corner
Intermediate steering
Intermediate top speed

More Rear Toe "IN"
More straight-line stability
More traction out of the corner
Less steering
Less top speed

i actually set more toe-in on the front in my rig after a couple of laps. i was going to flop my rear carriers and see how that works, but i dont mind having a little wider turn-in and needing to slow down a little before the turn if i can nail the throttle halfway thru it and be at a good speed exiting.

[badhoopty]

Originally Posted by johnnyh66

I'd like more braking power...

that would be an easy fix with a esc that was more racer tuneable and not setup for 10 year olds in a parking lot.

i dont care at all for the throttle and braking profiles of the velineon setup.

[thzero]

Originally Posted by badhoopty

but i dont mind having a little wider turn-in and needing to slow down a little before the turn if i can nail the throttle halfway thru it and be at a good speed exiting.

Slow in, fast out. That was the mantra we preached on "on-road" sim racing, which is true in the real world too, not sure how much on dirt it really pertains.

Brake? Whats that? I did set the ESC to have some drag brake, but was also going to reduce the braking force on it too.

[badhoopty]

just got a message back from the guy i bought the slash from, my diffs are stock.

[JHTreyIII]

Originally Posted by Die-Laughing

What servo are you using? I don't have the best servo (Hitec 965) but, my truggy apparently turns in pretty well. I got a 7965 for the Sc10.

Hell if I know. It looked like Jasons slash was dialed in pretty well. I drove Treys slash and it felt weird. It felt like front wheel drive. If you were on the power hard, you couldn't turn.. It would just push. I'm sure its doing something like that in the corners as well. Try playing with that center diff like you said. That thing is gonna fly with some tweaking.

I have a Hitec 5625 on it. Not super high torque but it has metal gears and is pretty speedy. I probably should put a BEC on it. Hopefully the diff tuning will help.

Interesting that Johnny was also having some steering issues.

[thzero]

Originally Posted by JHTreyIII

I have a Hitec 5625 on it. Not super high torque but it has metal gears and is pretty speedy. I probably should put a BEC on it. Hopefully the diff tuning will help.

Interesting that Johnny was also having some steering issues.

Well the diffs, front rear and center, do play into the ability of the vehicle when turning. In general this sums up most of what I've seen on the internet about diff tuning.

DIFF OIL THICKNESS CHARACTERISTICS
Front
Thinner
• Increases steering into corners (off-power)
• If oil is too thin the steering may become inconsistent, especially it can lose forward traction (and steering) during acceleration out of corners
Thicker
• Increases stability into corners during braking
• Increases steering on-power at corner exit

Center
Thinner
• Front wheels unload more during acceleration
• Decreases on-power steering (reduces oversteer)
• Easier to drive on rough tracks
• If a high-power engine is used you could waste too much power and sometime “cook” the oil in the center differential because it “overloads”
• More off-power steering
Thicker
• More all-wheel drive effect
• Better acceleration
• Increases on-power steering (reduces understeer)
• Better suited on high-bite, smooth tracks
• Car can be more nervous to drive especially if a high power engine is used - you might need to be smooth on the throttle

Rear
Thinner
• Increases cornering traction
• Increases steering into corner
Thicker
• Decreases rear traction while cornering
• Reduces wheelspin

Just some general setup guidelines that are pretty generic.

¦Camber:
This is the angle that the wheels lean left or right when looking at the car from in front or behind the car.
Camber can be POSITIVE (top of the wheel further away from the chassis than the bottom) or NEGATIVE (top of the wheel closer to the chassis than the bottom.
Note: Generally, you will NEVER need to use POSITIVE camber.

¦Caster
This describes the forward/backward angle of the steering block in relation to a line perpendicular to the ground.
A higher caster angle has the effect of leaning the tyres into the direction of the corner.

More caster will result in:

¦better straight line stability
¦less steering on corner entry
¦more steering mid corner and corner exit
Less caster will result in:

¦decrease in straight line stability
¦more steering on corner entry
¦less steering mid corner and corner exit
To adjust caster, you would normally have the change the steering blocks out for ones with a different amount of caster on them.

¦Toe Angle:
This is the angle that the wheels point left or right at when looking from above the chassis.
Toe can be IN (front of the wheels pointing towards the chassis) or OUT (front of the wheels pointing away from the chassis).

Front:
More Toe In:

¦Increases understeer
¦Less steering at corner entry
¦Decreases straight line stability
More Toe Out:

¦Increases oversteer
¦More steering at corner entry
¦Increases straight line stability
Rear:
More Toe In:

¦Increases understeer
¦Increases stability on power
Less Toe In:

¦Decreases stability on power
Generally the Rear wheels should never have toe-out, but the Front wheels can have either toe-out or toe-in

¦Shock Damping/Springing
Shock absorbers and the springs you use are one of the most critical elements of any setup.
Shock springs:
A Stiffer spring (higher rating):

¦Make the car more responsive
¦React quicker to steering
¦Better suited to tracks where bumps are quite low
A Softer spring (lower rating):

¦Allow the chassis to roll around a little more
¦Tend to perform better on bumpy tracks
¦Make the car less responsive
Damping:
Damping mainly helps with a change to the cars suspension, such as a bump or braking for a corner. It is managed through the use of a shock oil and a shock piston.

Shock oil is rated on how viscous it is with a higher rating meaning the oil is thicker and more viscous.
Shock pistons have a number of holes in them to control the flow of oil through them.

Front:
Softer Damping (either through thinner oil or a piston with more holes):

¦Slower steering response
¦Decrease initial steering
¦Increase steering at corner exit
Hard damping: (either through thicker oil or a piston with less holes):

¦Faster steering response
¦Increase initial steering
¦Decrease steering at corner exit
Rear:
Softer Damping:

¦Faster steering
¦Increase rear grip at corner exit
¦Decrease rear grip under braking
Harder Damping:

¦Slower steering
¦Decrease rear grip at corner exit
¦Increase rear grip under braking
Getting shock damping and springing right for the track conditions is something that can transform the way your car handles.

¦Droop/Downstops
Droop is a much discussed topic (how to measure it, what it is etc) Put simply, droop is the amount of difference between the ride height and the limit for the suspension arms.
Downstops are found on most modern touring car chassis and are used to limit the amount of downtravel that the suspension arms have. When someone running a touring car says they are running "5 droop on the rear and 4 on the front" they actually mean that the suspension arms are measured at 5mm below the chassis level and NOT the actual droop measurement.

To measure droop, use a ride height gauge and take a measurement of ride height at one end of the vehicle. Now lift that end of the vehicle slowly until you get to the point where the tyres leave the ground. Measure the ride height again at this point. The difference between the first and second measurement is Droop.

To measure downstop travel, remove the shocks and any anti roll bars you may have installed on the vehicle. PLace the chassis on some droop blocks and make sure the suspension arms drop under their own weight. Now take your droop guage and take a measurement from the bottom of the suspension arm. This can be changed by turning the downstop screw in that suspension arm (higher number on the guage = less downtravel).

Note: Generally, the terms droop and downstops are used interchangeably when referring to a Touring Car setup change.

¦Ride height
This is how far from the ground the chassis is when stationary. It is normally measured in mm. You can raise or lower the ride height depending on track conditions.

[BAD 1]

I use 0 drag brake, due to the fact that when in mid air drag brake would cause your front end to dive plus you want to roll into the turns. IMO. Rick, There are Transponders that you can buy for about $90.00 to $100.00 to record your times and amount of laps. Most races are set up for 5 min heats. Just got back from the Lake and had a good time. Fish were jumping this morning starting to cool off.

[BAD 1]

Dam, ZERO thats some good information. Good to see that your doing your home work.

[thzero]

Originally Posted by BAD 1

I use 0 drag brake, due to the fact that when in mid air drag brake would cause your front end to dive plus you want to roll into the turns. IMO.

True. However, considering that the SCT tend to have a parachute affect, I'm not sure that is all that problematic. I think I had only set it up for 5% drag brake, so not a lot.

[BAD 1]

Your right about the parachute effect. It is really noticed in 2wd. I add weight right behind the fromt bumper to bring the front end down and handle the turns better. No need for weight on my 4wd its heavy enought.

[JHTreyIII]

This is funny. Should we be called the N.I.R.C.S.C.T.?

[johnnyh66]

Originally Posted by JHTreyIII

This is funny. Should we be called the N.I.R.C.S.C.T.?

I think NERDS sums it up.

[thzero]

Originally Posted by johnnyh66

I think NERDS sums it up.

Got a buddy that races over in Rockford, mostly 2WD 10th scale buggies. But he used to do quarter scale midgets, should see if he still has some contacts... thats a trip to watch.

[badhoopty]

my slash had pretty bad turning as well compared to ricks slash and definitely waaay worse than the buggy. i would try to be on the brakes to plant the front as i turned in, little bit of throttle thru the turn, then at my apex nail the gas.

[Die-Laughing]

My stampede has a shorter wheelbase, lighter body and a wing on the back.. Maybe that makes the front end lighter a bit.. Although, I did find myself braking hard into corners, lightening the rear and creating a bit of oversteer to help me around the bend.

[johnnyh66]

Originally Posted by badhoopty

i would try to be on the brakes to plant the front as i turned in, little bit of throttle thru the turn, then at my apex nail the gas.

me too for the most part... a few times, I got good results from
letting off throttle before going into (no brake)
then double tap throttle going into to break the rear loose
and full throttle from apex out.

[neillarson]

Ordered a couple of 5900MHr 60C 2S hard cases today. They will be here Friday but still not sure I will have a truck, lol. So I may be out this Sunday but I will be ready next Sunday.