Hi Volker,

I am trying to build a Cup setup for IRP (PWF version), and the information I have been working off is as follows.

Thiago Moya suggested that Richmond is a good base and I started with your Richmond setup with different diff / gearing (IRP is shorter 0.69mi).

In determining what other changes to make I have compared Andy Wilkes Richmond and IRP setups to see what type of changes he has made in the hope that I can gain some clues.

It seems like he has tried to loosen the car a little compared with Richmond, and his changes are as follows:
* 50lb more springs on the rear
* 50lb more RF spring (RF now 50lb stiffer than LF)
* More rear sway bar 0.25 inch (cf 0)
* Trackbar higher by 1.00 inch
* 0.3 deg less RF negative camber (-3.00 cf -3.30)
* Couple of other minor things like tire pressure down 0.5psi on RHS

In looking at it in light of advice you have previously given, I don't really want to add more rear springs (the car is not bottoming out), nor add more RF spring (as RF then greater than LF), and I can't recall ever seeing you use the rear swaybar. Hence, I am a little confused.

My intuition tells me to use less negative RF camber than Richmond as Andy has done, maybe make a similar trackbar adjustment and adjust the weight back to try to achieve a looser car (which is what I think Andy was trying to do). However, Andy didn't adjust weight at all between the two, so I could be going off in the wrong direction.

Any suggestions as I don't seem to get weight adjustments correct on the short track chassis (much easier on chassis 2 where you just put it back as far as you can with the car drivable) and am a little unsure as to whether I am going in the right direction. I know I am asking about a track you don't run, but hoping you may still have some pointers.

Relevant track.ini info from Richmond and IRP_PWF is below.

Any help appreciated.

Thanks

Brad


Richmond Track.ini Info (14 degree banking)
track_tire_heat = 1.08
track_tire_wear = 0.51
track_asphalt_grip = 1.10
track_concrete_grip = 1.08

IRP_PWF Track.ini Info (11 degree Banking)
track_tire_heat = 1.15
track_tire_wear = 0.53
track_asphalt_grip = 1.10
track_concrete_grip = 1.14

I've never even downloaded IRP, so I really don't know if you can run it looser than at Richmond or not, as this doesn't only depend on the banking and grip settings, but also on the transitions into and off the corners.

Springs all around should always be as soft as possible as this gives you the most possible grip. The RF spring is not a setting to adjust the balance of the car with, and if you stiffen both rear springs you won't change it significantly either, the only spring adjustment to loosen the car up would be adding rear spring split (i.e. making the RR spring stiffer than the LR).

Yeah at the flat, short tracks you usually run more front weight and loosen it up with track bar or rear spring split instead, otherwise the car won't rotate on exit. I would assume that track bar works better than spring split just as it does at Richmond / Phoenix / Homestead, but even if this is the case you'd still have to figure out the best front weight vs track bar combination on your own.

With ST chassis, -7° of RF camber works best at most tracks, Richmond is an exception where I only use -4°. I wouldn't expect to run it even more positive than that anywhere, and generally, less banking requires more negative camber.

Thanks Volker, much appreciated. I completed my IRP setup and posted in the Setup Exchange forum.

One thing that I have observed is that chassis 3 is commented at "short track" in the track.ini, whereas I would prefer the comment "flat track".

Bristol is a short track, but uses chassis 2 because it is banked. However, I-70 PWF (30 deg banking, 0.49 miles) amongst other add on tracks use chassis 3. This may explain why I had difficulty making a setup for this track/

My assumption is that the normal rules of RF -7deg camber would go out the window, and the camber could be far lower than Richmond?? Salem DR is another example (33 deg banking, 0.555miles, chassis 3), and Thiago Moya's setup has RF Camber -2.

Perhaps the trackmakers should have used chassis 2 on some of these tracks like Papy did with Bristol.

Anyway thanks again.

Brad

Your observation is correct, the ST chassis (chassis 3) is mainly used on flat tracks, but then again not on every flat track, Las Vegas uses the SW chassis (chassis 2). The -7° RF camber rule only goes for ST chassis, with SW chassis you run way less, ranging from about -1.50° for high-banked tracks to -3.50° for rather flat ones.

I would always start with a setup for the same chassis type when I come to a new track, rather than a setup for a more similar track where a different chassis type is used, as the way these things are set up is often very different.

Thanks Volker.

I guess my point is that for a track with high banking and chassis 3, there are no similar setups made by yourself that I can use as a base, so I will be wandering around in the dark on those.

It is a shame you have never downloaded them, as IRP, Milwaukee, Nashville, and Thompson are very nice tracks, and I probably don't do them justice as a setup maker.

Whilst I am going to try to update setups for the higher banked PWF tracks despite them being on chassis 3, I will redo Evergreen PWF setup first (8 deg banking, 0.65miles), as it should be similar to IRP.

One other question I have is regarding toe-out. I note that you have adjusted toe-out to +0.2 on the intermediate tracks, but not short tracks. Is this because it doesn't work, or because you haven't had time to change all the setups yet?

Thanks

Brad

Running positive toe out reduces RF tire wear, which is favourable at the cookie cutter type of tracks. The downside of positive toe out is the handling on entry, the car just won't turn in very well anymore, which isn't a problem at the cookie cutters. At many other tracks, especially short tracks and tracks with less banking, handling is more important and RF tire wear is less of an issue, so you're better off without toe out there.

Volker,

In relation to your advice regarding camber...

... I am now trying to build a new setup for Nashville PWF which has 18 degrees of banking. I have found that the inside RF heats up a lot if I run more negative camber than -4 deg, and making a trackbar / rear spring split adjustment to compensate makes me oversteer coming off turns 2 and 4 (I didn't try negative rear spring split with trackbar as this seemed offsetting).

Is it likely that any track with banking > 14 deg will require less neg camber. Your post suggests -4 is the minimum negative camber you would ever use, but I can't seem to get good setups for the banked short tracks using chassis 3 with this rule.

Also, for chassis 3, is it true that the shorter the track, the less likely you need rear spring split / trackbar. (I am comparing your Martinsville (no rear spring split / trackbar) with your Richmond / Phoenix etc)?

Sorry to bug you with so many dumb questions! Your help is always appreciated.

Thanks

Brad

I've only run cup tracks with chassis 3, which doesn't include any with more banking than Richmond. Maybe it works like in SW chassis and you need more positiver camber if you race at tracks with more banking, maybe -7° actually works best everywhere, no idea.


It's mainly the radius of the corners I think; in very tight corners you'll rather have issues bringing the power down on exit, whereas there is usually a problem with understeer in the center and exiting long sweeping corners.

Thanks Volker, your help is awesome. It is not often that I am able to get advice from one of the best in the world on anything, so I am going to push my luck and ask another question...

By the way, I finished my Nashville setup and posted it (ended up with RF camber -4 deg).

I have now moved to Coca Cola with chassis 5. I thought I had a reasonable setup, but forgot that many years ago I had edited the track.ini to tone down the AI. On the original unedited track.ini my setup is crap.

I have basically used your Daytona setup with:
1. Spoiler down to 45deg with weight forward to compensate;
2. Stiffer springs on the back and left front to stop bottoming out;
3. tyre pressures similar to chassis 2 (28/48).

Still testing it, but it seems ok with camber 2, -7, caster 6,-2 and shock settings as per the chassis 1 setups. I find the car to be quite erratic and difficult to control with this chassis, but I may just need more setup work.

Do you have any tips for chassis 5?

Thanks as always.

Brad

Not really, I never drove it at Coke seriously, only at some of the speedways, mainly California. At the latter, I ended up using chassis 2 camber, caster etc., the main difference was much more front weight obviously (as the car is way too loose otherwise), very stiff rear springs to get the spoiler up into the air (which is probably not favourable at a flat out track, as it increases drag) and some rear spring split. I would assume that the typical SS front springs and front shocks won't work too well either at Coke.

Thanks for the advice, Volker. Am still finding chassis 5 a bit tricky to control, but will keep working on it.