With the 2014 NASCAR iRacing Series set to get underway later this week, iRacingNews is introducing the first in a regular series of articles by Eric Isenbeck designed to help those many iRacers who are not part of multi-driver teams develop set-ups for the Gen 6 Chevy SSs and Ford Fusions they’ll be racing in the series. While iRacingNews makes no guarantees that you’ll morph from mortal to alien by following the the ideas, concepts and opinions in the articles, we do hope A Team of One will help illuminate some of the art and science behind the black art of chassis set-up – Ed
Set-up building is often considered one of the hardest feats to master in motorsports. There are about 50 different variables in iRacing that can be changed or adjusted that can change the handling of a car.
I have been a member on iRacing for almost two years now. I was always “ok” at fixed racing, but I could never understand how to make a fast set-up. In the real world, I race Bandoleros and Legends as well as the weekend go kart races. In 2013, I have been in contact with and associated myself with several ARCA Racing Series teams. I have quietly been learning the tricks of the trade in the real world as well as from well-known set-up builders here on iRacing. I hope to advance my career in the near future to a regional or national level stock car touring series. (Cue the Super Bowl Maserati commercial!)
Tony Gardner turned heads in December when he announced that the road to pro will no longer be split into 12 week seasons. The NASCAR iRacing Series will now be the qualifier series for the NASCAR iRacing.com Pro Series. The top 20 drivers in overall points, without a PRO or PRO W/C license, at the end of the grueling 26 week season will be offered a PRO license. The world’s best sim racers will be running all season long in the hopes of earning the elusive black stripe.
“A Team of One” will be a weekly column that will assist drivers in building their set-ups each week for the NASCAR iRacing Series. You don’t need a fancy, high-class, top end team that uses telemetry (OK, maybe you do need telemetry) to be a successful driver and set-up builder. Each week, I’ll walk you through the process of building your set-up for the NASCAR iRacing Series races.
Week 1 brings us to the high-banks of the Daytona International Speedway. Restrictor plate races bring a unique set of variables, cheating methods and variations of lucky underwear to the real world. While we can’t use buffed roof flap spacers like Austin Dillon (see picture below) or vivid variations of under garments, we can use what iRacing gives us. iRacing provides a level playing field that limits the search for speed to the legal adjustments.
Take a look at the roof flap on Dillon’s car. This picture that shows why the 3 car was at the top of the speed charts in the preseason test session this year (thanks to Dustin McGrew and Mark Shaffer for pointing this out in the forums.) Last year at Daytona, several teams had their roof flap spacers confiscated by NASCAR. More than several, actually. 15 teams from the NASCAR Sprint Cup Series and 16 from the NASCAR Nationwide Series were found bending the rules. You may be thinking “It’s barely half of an inch, what does it matter?” Well, that half an inch can take a tremendous amount of air off the back spoiler. My point in explaining this is to show you that iRacing has “static” cars compared to the real world. In iRacing, we need to use basic adjustments to get the most speed we can out of our cars at Superspeedways.
*Make note that the two main points to look at in a superspeedway set-up are:
• A front splitter seal
• Air off the spoiler
Let’s begin the set-up building process by looking at the track and accessing what needs to be done. Daytona International Speedway was repaved in 2010 and scanned shortly after by iRacing. This means we have a nice smooth surface to drive on instead of a driveway that has a 200 year old oak tree with roots underneath it.
On to the set-up. We don’t need to worry about bottoming out that much anymore which means we can attack the surface with the splitter as close to the ground as possible. That means we need to get the ride heights as low as possible. When the ride heights get lowered it seals the front splitter and keeps the spoiler lower. While that plays a big factor, one of the most crucial things iRacing members may not know is that cross weight and nose weight play a big role in overall speed of the car. The iRacing garage tells you that more cross weight means more understeer in left hand turns and more oversteer in right. That’s true, but it also changes the overall speed of the car. It may not be extremely noticeable at you average mile-and-a-half track, but it is an absolute necessity at a restrictor plate track.
If you have read the NASCAR iRacing Series forum lately you have seen that some drivers have been complaining about the weather iRacing has set for the iRacing Daytona 500. The weather will allow for some tandem racing. In some testing that I had done, I found that the car needs to have a good amount of nose weight to push or be pushed. The fixed set-up that iRacing provides everyone with has 48” of front ballast. I would not deviate too far from this number as it increases nose weight and will significantly increase the handling ability that your race set-up will have while in the draft.
“Superspeedway set-up building is completely different from any other form of set-up building.”
Next up on our check list is track bar. The track bar needs to be raised as much as possible. I would start with a 15.000 setting on the right side and a 12.000 on the left side. The higher the track bar is, the less drag you have. As far as tire pressure goes, you want as little resistance as possible. Think of an inflated basketball and a deflated basketball. You want as much “bounce” on the basketball as possible so it will be easier to dribble. Think of the basketball bounce as speed at a superspeedway. Start with a near-max RF tire pressure and take out about 10-15 PSI on the LF and RR tires. Run the LR at about 25-30 PSI below your RF. But don’t forget that our whole goal is to as much air off the spoiler as possible. The more air in the tire we have the more air we have hitting the spoiler since it is raised. I won’t give you exact numbers, but try to find the right combo of low resistance in the tire and a low spoiler height.
Run a bottom truck arm mount on the left side and a high truck arm mount on the right. This acts the same way that the track bar does (higher mount=less drag.) Truck arm mounts are also a great way to change cross weight. Try to play with the mount to fine tune the cross weight. As far as camber goes, run as much as possible on the front and very little on the rear (I will show you why when I talk about caster.) All of these components help reduce resistance and scrub when at speed.
You must also run enough ARB to seal the front end. The anti-roll bar helps stabilize the front end and achieve the seal we want on the splitter. However, it also increases downforce. Downforce is not a good thing on a superspeedway since it will decrease top end speed. Run enough ARB to seal the front, but not too much as it will lower your speed. Caster needs to be maxed out. When you add caster, you increase camber at speed. We are going to be running a lot of camber because it reduces the surface area of the tire that is touching the track. The less area of the tire that is touching the track the less scrub and resistance there is from the tire.
Springs need to be low; I personally wouldn’t change them from the fixed all that much. Low spring rates help keep the front splitter and spoiler down in addition to increasing mechanical grip. Also, run as much truck arm preload as possible. Increasing the preload will decrease drag (same concept as the track bar and truck arm mounts.) I found that the fixed set-up shock package will handle ok. The biggest factors on front end suspension at superspeedways are bumpstops and packers. Both of these hold the front splitter up. The goal is to run as little bumpstop and packer as possible without putting the splitter in the asphalt. This is going to be the hardest and most crucial part, but you have to pinpoint the right bumpstop and packer for your set-up.
Superspeedway set-up building is completely different from any other form of set-up building. Tweak the camber, tire pressure, springs or anything else and try to find as much speed as possible. I also have to thank Eric Hudec as he provided great insight on a unique form of motorsports.
Each week, I would like to do an “Ask Me Anything” as far as set-ups go. If you have a question regarding the process of set-up building, send me (Eric Isenbeck) a PM on the iRacing forums and I will answer your question in next week’s article and hopefully provide a visual as well.
In my opinion, superspeedway set-up building is extremely dry if you are not pushing the rules to the limit. Anyway, next week is Phoenix and I will be able to go in depth on specific parts of the suspension. Phoenix still has the “old” surface that was seen before it was repaved so it will be a challenge. I will show you how to get the car to travel well over the bumps and how to control the lateral grip (how to not junk it) on corner exit.