John.

iTrader: (11)

Outside of tires, if I could only pick one or two it would have to be RIDE HEIGHT and DROOP.
Everything you change will make a difference, but I have found these two simplest of adjustments to make the most difference.

mcion

iTrader: (32)

I always thought more droop was for a bumpy track, why would you need more droop for a smooth track?

vlad_vy

It's only one of many items that confused us in these setup guides. It's depend from how you measure that item, relative to what??? Ground or anything else? Between mounting points (as Losi)?

Drop from ground - more drop, less free movement of suspension, for smooth track.

Lonestar

iTrader: (14)

Interesting post.

different people will feel different setup changes do different things.

My answer to the original Q (key drivers but tires)
- diff oils
- brake bias

if you have the right tires and as johnnyT smartly noted a "mechanically healthy" (symmetric, no tweak, no bind, reasonable slop, "balanced" f/r fresh shock oil springs and swaybars,...) car, you're 80% there. Diffs and brake bias then take you 95% there. The remaining 5% doesn't count for most of us as there's more ROI when working on driving/practicing than tuning for setup optimality...

IMHO

Paul

NitroFreakManHo

iTrader: (3)

Agreed. It's amazing how overlooked these two setup options are, considering how instantly their effect are felt on the track. They are simple and fast to do too which is a bonus trackside.

dsl

iTrader: (1)

Here is Mark Pavidis' list of tuning importance. It is from a magazine a few years ago listed most important to least important:
Tires
Front shock location
Rear toe
Rear shock location
Shock fluid
Diff fluid
Foam inserts
Front camber
Rear camber
Ride height
Front toe
Caster

Lonestar

iTrader: (14)

different drivers, different opinions... at least 2 interesting things here, droop not mentioned, and caster dead last

thanks for sharing

Paul

johnny t

iTrader: (10)

what has the most effect, most importance or most convenient to change are not all the same thing. The pavidis list might just be how he rates things with all three of those factors considered.

example, for me ride height has a strong effect and is convenient but I give it less importance. I keep a consistent ride height as changing it has too much effect on way many other things. It is something I will play with last if I can't get via other ways, or as a last ditch effort to fix handling on the warm up laps before a heat...

caster may have a strong effect but with alot of cars is very inconvenient to change. so down with its importance in putting together a setup strategy on raceday.

I guess thats another factor people have to consider, what setups changes you can play with on practice/test day may not correlate on racedays. and having a coherent plan of what you can change when certain conditions come up is very valuable IMHO. and it might not always be what gives you the most effect but is convenient as well.

PTP Racing

iTrader: (2)

I would say the BIGGEST changes are springs and sway bars. These 2 adjustments make the biggest changes in traction of any I can think of. I might change ride height a little based on how rough the track is but I usually keep the difference between front and back the same and thats where the ride height has an effect on handling. I'll change droop but usually that has more to do with traction rolling or how rough the track is. If I need more or less traction I go to sway bars first and springs second. A softer sway bar or softer springs will allow the car to put more of its weight where you need it for traction. Shock oil is mostly for the same thing as droop almost because you want it thin for rough or thick to slow suspension reactions to stop a dive or traction roll.

For me if I go somewhere and Im struggling my first change will be the sway bar on the end of the car Im having trouble with. If I need more steering I will use a softer sway bar or if Im really loose I'll use a softer one on the rear or if traction is high and I need more steering a stiffer rear sway bar will give some of the effect of a softer front but without making the car prone to traction rolling. Then springs and shock oil to match the oil. Softer springs allow the car to squat more both on acceleration and decelleration. When your car leans or squats it puts more of the weight on the wheel or wheels its leaning towards and if youve got the right tires weight equals traction. The speed at which the shocks react is controlled by the oil. I mostly match the oil to the springs Im running and aim for the car to settle evenly when dropped. Next would be alignment. Toe makes a pretty big difference but IMO camber is just used to get the best contact patch possible. Caster is an adjustment I use when switching from tight to more open layouts and antisquat is mostly set for how rough the track is. Roll centers are a great adjustment but few really understand it well enough to make good decisions about adjusting it. Im still learning or should I say trying to figure it out after 10 years racing. The last thing I would consider changing is my diffs. IMO its too much work for too little gain.

Everything is a balancing act. You wouldnt want to run 80wt oil and your softest springs and you shouldnt go too far with an adjustment on the front without considering an opposite adjustment in the rear.

Also another thing to consider is driving habits. I know a lot of people who drive way to fast into corners then complain their car is pushing. Sometimes the problem is the line taken or speed its taken not the setup at all. My bet is that if your setup is in left field then your driving probably is too....just sayin.

John.

iTrader: (11)

This is true. For example Adam Drake rates ride height and droop very highly. Easiest thing to change and has most effect. Thing is you don't have to make the changes huge, just a few mm here and there. This is what I have experienced too.

To be honest I'm a club racer. Between social chit chat, marshalling, engine tune and racing I don't have the time to be pulling apart shocks, pulling diffs apart and changing oils. Seriously who are we kidding here. If they aren't broke they aren't coming apart at the track. I will only change the easiest things like tyres, ride height, droop and maybe springs and sway bars. I won't touch anything else unless it's broken. I want to race and have fun. If the car is that bad I will just drive around it.

Jaz240

iTrader: (52)

The thing that amazes me is I can go out and have fun and be relatively fast regardless of how bad my set-up may be at the time, as Long as I have the right tire and a good working engine, I'm having fun