Dirt: It’s that painfully slippery surface that causes most of us a 1x or a 2x at some point; a 4x if we are unlucky enough to really lose it.  It’s something that will take a perfectly fine race car and send it 180 degrees backwards into a barrier or sand trap.

For most road racers dirt is evil.  Most oval racers don’t even worry about dirt while racing in their paved coliseums.   But for one group dirt is for racing.  Pavement?  It’s just for getting there.  From short, bullring dirt tracks to miles of rally stages, this group thrives on sim racing in the dirty stuff.

Motorsports on dirt takes many forms across the world.  It’s best known in America for dirt oval racing, while the rest of the world enjoys rallying.  Then there are the off-road racers, who not only play in the dirt but soar over mounds of the stuff.  So the big question that comes-up weekly in the iRacing forums is: “When is dirt coming to iRacing?”

Dave Kaemmer, co-founder of iRacing.com, recently took some time to talk about dirt and the complications it brings from the developers’ standpoint.

Q:     As a motorsports simulation developer what goes through your mind when you see a member of iRacing asking for dirt racing?
A:     I always think about the technical issues first—mostly surface modeling, and graphics.  Then I think about how cool it would be—and it would be pretty cool.  Then I wonder about opportunity costs—might we be better off doing something else?

Q:     What are some of the difficulties about bringing dirt racing into the service?
A:     Surface modeling and graphics.  We’d need to scan some dirt tracks, some off-road courses, and figure-out how to render and manipulate changing track geometry.  Of course, we could keep the track static (not changing), but where’s the fun in that?

Developing artist's conception of iRacing sprint car on dirt? Easy (relatively). Developing practical model of dirt track racing for iRacing? Not so much.

Q:     If and when iRacing brings dirt racing into the service, will multiple forms of dirt racing be looked at, like rally, off-road, and dirt oval?
A:     If/when we do dirt, that would be ideal.  Obviously the surface and force modeling would work for all of them.  We’d need to license and build some different vehicles to do off-road and rally.

Q:     It would seem dynamic surfaces would be key to capturing the feel of dirt racing, and an ever changing track.  Is this something iRacing has looked into? Is it possible to not only have changing grip, but also movement in the surface?
A:     Anything is possible, but the dynamic surfaces are difficult for many reasons, especially in the multi-player environment.  How do we make sure every driver’s track surface is the same, for example.

“We could keep the track static, but where’s the fun in that?”

Q:     How would you approach laser-scanning the track surface when all of these things come into play?
A:     A laser scan would still be good for getting basic topography, and examples of surface ruts, etc. as well as all the usual off track visuals.  Then we’d have to figure out how to “bulldoze” the surface from time to time, and allow it to be modified by the vehicles racing on it.  We might have to move to a different type of laser scanner for doing many mile, point-to-point courses.  For ovals, we’d just do what we already do.

Q:     I have seen some members say that a new tire would need to be developed for dirt.  Would this need to happen or is the tire model something that works no matter what surface it is running on?                                                                                                                                                                     A:     The tire we have is probably good, but we’re need modeling of the dirt itself.  A lot of the forces on a dirt track depend on the dirt and its properties.  On asphalt, we don’t have to worry about the surface breaking up before the tires lose grip.  On dirt, the “tire” forces are more often dirt forces.

“The dynamic surfaces are difficult for many reasons, especially in the multi-player environment.”

Q:     We have seen from a few of your posts about the data you have on grass, the ‘cow’ data.  Have you looked for data on the properties of different types of dirt and clay?
A:     I’m always on the lookout for data.  There’s a lot of research into “terra-mechanics,” primarily since military simulations of tanks have to deal with the physics of dirt.  It’s interesting, but sand, dirt, clay, even gravel are all pretty much the same except for the sizes of the particles making them up; and their water content.  Of course grass and other plants add complications.

Q:     SODA Off-Road Racing seems to be the only dirt game that you have been connected to, through Papyrus.  Did you have a part in that title?
A:     Shawn Nash developed SODA, pretty much by himself.  Still amazes me.  Papyrus was the publisher, but Shawn did it as an outside developer, so it wasn’t our code.  Of course, Shawn is one of our engineers, so if we do dirt he knows all about mud-pumping forces and 20” of suspension travel . . . and lots of other things.

“If we do dirt (Shawn Nash) knows all about mud-pumping forces and 20” of suspension travel . . .”

Q:     Through the years there have been very few titles for dirt racing compared to those for asphalt racing.  Why do you think this is? Is it a lack of market or just something harder to do than a paved surface?
A:     I think it’s a combination of both.  The best-selling dirt games have been rally games, for the most part.  The difficulty of doing it certainly plays a part, since difficult = costly.

Q:     In your mind where does iRacing need to be on the paved racing side before focus can turn to dirt.   Does the status of iRacing’s paved racing even play a role in when dirt comes?
A:     There are still a lot of features on pavement that are probably more cost-effective for us to do, and for which we’d probably find a bigger audience.  Endurance racing as teams, for example—there’s just a huge list of features we’d like to get done.  Consider this as well… would drag racing be a bigger deal?  How about motorcycles?  Of course I know what you’re thinking:  dirt bikes!

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Dave, do dirt. There are a LOT of people that don’t buy the iRacing surface because they don’t have dirt. Trust me. I personally know at least 10 of them, and I’m not exaggerating.

Bill Tomer
December 2nd, 2011 at 8:32 pm

Im like bill. Ive showed the sim to 8 of my fellow dirt racers. they all liked iracing but wouldnt purchase it because of the lack of dirt racing. they would all rather play there ps2 then race on asphalt. if anything just make a few dirt versions of the asphalt tracks you already have and just run the sprint cars on them as a test…

Cy strickland
February 26th, 2012 at 3:12 am

Dirt would be HUGE! We have fun racing on static tracks now, why wouldn’t we have fun “making due” with static dirt tracks as well? I strongly disagree with your notion that there would be no fun in that…

Scott Hunsinger
December 2nd, 2011 at 9:34 pm

I agree with Scott’s comment. There is a way bigger market out there for dirt racing than most would think. And some of the current dirt racing going on right now on Rfactor is really good. I too would rather have dirt racing on a fixed track surface than to not have it at all. For a sneak peak of whats going on right now with dirt racing check out Sim Vision Network / Top 5 Motorsports this Sat. 12/3 @
9 pm EST. Sorry to say but I am currently having about 10 times more fun racing dirt on Rfactor with the big block modifieds than I am on these mostly one lane pavement tracks. And I’m leading the tour mod points here on Iracing. So I’m doing both but having more fun by a long shot on the dirt side

Herb Engelhart
December 2nd, 2011 at 11:11 pm

Dirt would be so much fun. I personally enjoy it more than asphalt racing. Please look into this!

December 2nd, 2011 at 10:26 pm

Rallying would be awesome, I can understand the difficulty especially with multiplayer racing.
With that said… With Rally Stages we run by ourselves…
iRacing can then build a stage and use it as an active experiment into Dirt racing while we enjoy fighting each other for top stage times…

Marcus Caton
December 2nd, 2011 at 10:36 pm

Its much easier than it sounds. Just load the OTM for the dirt tracks.

Code Redd
December 2nd, 2011 at 10:38 pm

Hopefully they start working on this around the time I graduate with my Computer Engineering degree 🙂

December 2nd, 2011 at 10:39 pm

Improve the general tyre model first, don’t pretend its roundabout perfect, before you start new things anyway.

Herb Jenkins
December 2nd, 2011 at 10:41 pm

I’m sick of seeing people asking for dirt racing.
Give an inch and some freaking body wants a mile.
Keep Iracing asphalt and keep improving it.

william morton
December 2nd, 2011 at 11:00 pm

A good track for dirt and asphalt you could scan is Elko Speedway. It is an asphalt and dirt track. And it is a nice facility. Elko has hosted both dirt and asphalt nationals for legends.

Michael Ostdiek
December 2nd, 2011 at 11:04 pm

There is one issue, what about when you slide the rear out and you’re looking at the infield? Would the camera automatically pan over to the right a bit?

December 2nd, 2011 at 11:52 pm

Im sure that it would be insane with the world of outlaws sprint cars or the big block modifieds!

Xavier Lauzon
December 2nd, 2011 at 11:57 pm

There is no way dirt, if done well, would NOT be very fun and even more challenging. A friend of mine named Andrew Caddell, who won the Ford Mustang Challenge a couple times switched over and won the TORC offroad truck series this year and he absolutely loves it! What I have always hoped to see from iRacing though, besides producing a 427 Cobra, is a tribute to their famous old program, Grand Prix Legends, and have a 1965-67ish series with the old GP cars. Now THAT would be cool. 🙂

Steve Lee
December 3rd, 2011 at 12:00 am

They announced the Lotus from 1967 about a month ago… so GPL 2.0 is coming!

Andrew Massey
December 4th, 2011 at 5:13 am

Very nice article, Nick — well-done! 🙂

John Bodin
December 3rd, 2011 at 12:00 am

The ending of the article is hilarious. Dirt bikes…pfft… Like iRacing would ever be able to do any better than MX Simulator.

Mark Zeidler
December 3rd, 2011 at 1:37 am

One of the biggest selling games for the PS2 was the World of Outlaws sprintcars. There hasn’t been anyone else come close to doing it propperly since. I know dozens of guys that run RFactor purely for the dirt sprints and midgets and nothing else, and to be honest It is VERY badly made. Surely IRacing is capeable of making the tracks and cars to a much better standard even if the surface is static to begin with

Brett Ireland
December 3rd, 2011 at 3:48 am

no bikes please.

Adam Green
December 3rd, 2011 at 4:34 am

Bring on the dirt even with a static surface it would be awesome!!!!!!!!!!!

Jerold John
December 3rd, 2011 at 5:37 am

There is a COLOSSAL hole in both the “gaming” and sim market for short course offroad racing since SODA. Games like 1NSANE and Rigs of Rods helped but being open-source sandboxers they can only do so much, and frankly I think most of them had more of a background in 3D modeling and physics coding than they did in short course racing (every time someone calls a Pro-2/U2 or Pro-4/U4 a “Trophy Truck”, God kills a kitten. Please, think of the kittens everyone). The original DiRT gave everyone a taste of short course with Carl Renezeder’s legendary old Flannery Chevy, Johnny Greaves’ Toyota, and Super Buggy/U-Buggy entries from Hawley and Schwalbe, but…ehh…DiRT’s still too much of an arcade racer and it’s not like they put much focus on it.

I know something’s in the pipe for a Short Course game, but there hasn’t been much of a splash about it anywhere and what little I have heard leads me to believe it’ll be more of an advertisement than a game, much less a sim.

Not begging to see dirt iRacing by the next build here, just chiming in on the state of demand…

Mike Budzien
December 3rd, 2011 at 5:53 am

While dirt racing would be fun, the amount of development hours required for this would not justify it at this time. “Dirt” by Codemasters already caters to this crowd, and does so brilliantly. How can you race “clean” in “dirt” anyway? By the time you finish a single lap you’ll have a 90x already. And oval dirt tracks? Weak. We all start with the legends car and by the time we finally get out of the rookie license, most of celebrate with champagne and bow to never again step in that hateful car unless it’s a hosted race where no ratings are in effect. Of all the short oval series, the only one with people actually participating (apart from Street Stock) is the Rookie Legends and simply because we’re forced to start there. Dirt Oval wouldn’t be much different.

“Keep improving what you already have and build on it,” would be my recommendation.

Enabling computer drivers for test sessions would be welcome by everyone and iRacing would be able to expand its customer base significantly. Spend your development resources on that. Everytime I have friends over they “love” the feeling of iRacing, but since they can’t test it with other cars, they don’t sign up. If iRacing gave us, their customers, the opportunity to entice our friends into joining by letting them practice in traffic, even if the opponents are not human, not only would we all be able to gain some valuable practice, but we’d also be able to bring in more customers.

In terms of new series, Motorbikes would take my vote. While there is a MotoGP “game”, what many long for is a “simulation” where racing wheels are actually supported. The track scanning technology wouldn’t have to be reinvented and all the new tracks would also work for iRacing’s existing cars. You’d be killing two birds with one stone and MotoGP is the next most followed motorsport after F1. Nascar (despite it being my personal favorite) is actually THIRD. So, spend your development dollars wisely and go for what the larger crowd craves for.

And while I’m not a big fan of Drag Racing, I could see this becoming a crowd pleaser based on iRacing’s demographics. Yet, it would be very restrictive considering drag racing only takes 2 cars. To take up a whole server for a race where there are only 2 players seems like a waste of resources.

Don’t take me wrong, I love rally, but based on iRacing’s Safety Rating system, I wouldn’t race it. There’s too much contact and sliding to be able to maintain one’s ratings healthy.

That’s my 2 cents.

Alex Alvarez
December 4th, 2011 at 5:54 am

Well first off Its a good move and Alex.A is so wrong,Right now Offroad and dirt track racing is gett so popuar out there and i think will be a huge success for iracing,short course trcuk racing is all the rage even in R/C racing right now,and is getting so popular with alot of fans.I cant wait to see dirt ovals,if they can do world of outlaws sprint cars and late models,not to mention they could use the street stock cars for rookie even on dirt.iracing keep up the great work and expand expand expand on al forms of racing ,hell i wpuld like to see iracing NHRA drag racing,Funny cars,Top Fuel,and even Pro Stocks.

Scott Turner
December 4th, 2011 at 4:55 pm

Alex’s post on dirt is spot on. Off-track, I’ve managed numerous businesses; good business comes down to understanding/balancing available market, risk and reward. The question is, would you pay more than your current subscription to race on dirt as well? How much more? How many resources does iRacing have? Would you prefer mediocre pavement to have mediocre dirt or would you like iRacing to continue being the premier pavement racing series. Not to mention the code of conduct, rules, tire and dirt models, new contact system (as dirt will have more contact), etc. It’s an entirely different business model and could put the entire business at risk. There are other options for dirt; stick to your core (pavement, with great tracks, cars and series). More tracks and other series; Porsche GT3 series would be awesome.

Chris Beaufait
February 15th, 2013 at 12:02 pm

dirt would be THE BEST additon to iracing , i race on Bolth paved and dirt surfaces and the best thing you can do for iracing is dirt, you could also have a donations “box” on iracing for some extra funds for the software and getting the new scanners . Dirt is one of the funnest and i think that even If you don’t like oval racing or dirt racing or havn’t tried it. its going to attract more than just dirt racers.

kyle hansen
December 4th, 2011 at 6:58 pm

Please just release a couple rally stages and model a handbrake and i will never ask for another thing from iRacing……..



Kevin Westendorf
December 5th, 2011 at 4:32 am

When the road side has enough cars and a weather model, go ahead and move on with dirt tracks/cars.

Right now there´s more important matters.

December 5th, 2011 at 9:21 am

people asking for dirt are crazy they are not even doing the basics for pavement racing and you want to have them doing dirt? 20 years time and we would be nowhere.

December 6th, 2011 at 5:24 pm

The way you describe the ‘dynamic surfaces” of dirt sounds very similar to how one might describe a asphalt race in the wet. Do you see this as a possible stepping stone to dirt? If you can have a race at Spa where it starts to rain or stops raining and over time the racing line starts to dry yet off line is still very wet or even getting wetter if it is still raining. How different would that be then the different grip levels of a dirt track?

Brett M. Waldrpep
December 8th, 2011 at 4:04 pm

Dave, I Like Many others on here would love to see what you guys could do with a dirt format, I’m very confident you’ll figure it out eventually, You ought to try and see if you can track down the RATBAG guys from Australia, they were the ones who did Dirt Track Racing Series of Games for PC, and Sprint Cars 2002 for PS2, Also You Can Look Up Either The World Racing Group Or IMCA For Different Classes Of Cars And Multiple Tracks, Keep Up The Excellent Work, When I Can Afford It And Update My Equipment I’ll Be Subscribing To You, Good Day My Friends.

February 23rd, 2012 at 11:59 pm

When it comes to dirt there are endless possibilities, differing classes, tracks and climates. Dirt racing in my opinion is the single most entertaining form of motorsports there is, and when you think about it, all the classes offered in iRacing would never exist in real life without dirt tracks and the roots of racing. I know that there are other sports that have higher numbers of fans but dirt racing has literaly hundreds of thousands of highly devoted, year-round fans. When I was first introduced to iRacing around two years ago I wanted to by it and set things up right away and then I was somewhat deterred when finding out that there was no forms of dirt oval. Adding dirt racing to iRacing would truley be the biggest challenge followed by the biggest reward you could make.

Seth Jones
March 16th, 2012 at 8:42 pm

Well i come from along line of dirt racers my self and would love to see dirt here. But in retrospect i think I racing needs to fix the bugs and stuff in Iracing now and hold of even for a little while on otherprojects. Most of the bugs get fixed but not all of them and some are pretty major at times.

Once i racing see a dramatic drop in bug and thing of this nature i think them moving to dirt would be a great benefit to there Sims!

Jon Sorensen
May 3rd, 2012 at 7:13 pm

I would like someone to cotcnat me how I can get involved. I did post in Facebook but really a crap shoot for any replies. I’m a moderate MTB but I have not had any opportunities to ride the trails in Fresno. Is there a membership fee to arrange a ride with someone who knows the trails around here? Thanks!

October 1st, 2012 at 6:02 am

Dirt would be a great idea. Especially if they’re considering terrain displacement! The would make every lap different from the last! I’d buy just to play some dirt tracks. There’s no truly good off road racing simulators.

May 10th, 2012 at 11:46 pm

I wish they would introduce a couple dirt classes. I grew up dirt racing as did most racers and to be able to get on here and wheel a sprint car or modified with a bunch of guys would be a blast. Asphalt is no doubt fun but however I would never let my service expire if Iracing offered forms of Dirt track racing.

June 19th, 2012 at 3:02 am

It would also reach a whole seperate group of customers interested in starting a membership. The monthly income would double in time without a doubt!

June 19th, 2012 at 3:05 am

I am aware of only one good dirt racing game and that is Richard Burns Rally. It came out in 2004 and there hasn’t been as good a rally game before that or after that.

People still play that game, I do too. There’s an active community of RBR modders and that game is practically being maintained by volunteers writing their mods. If you install it from original CDs, it’s unplayable on modern computers so you have to install some mods to get higher screen resolutions, etc working.

Please do dirt racing. I want to take a Group B monster out on a special stage in iRacing!

Riku Salminen
July 16th, 2012 at 6:08 pm

I am a 270 micro sprint car driver. They race on dirt and I can personally tell you that although asphalt is more popular I and a lot of others think that dirt is more exciting. I have iracing and I love it… but somethings missing… its all road courses and ovals likeusual but theres no dirt… I think that by making iracing have dirt track racing like sprint cars or big block modifieds you would be getting alot more customers… iracing would finally be complete with dirt track racing.

Grady Johnston
August 2nd, 2012 at 3:36 am

NR2003 had dirt tracks and cars made by the user community. the late models were very good for the day imo, and that was based off the papyrus engine, so why would it be so difficult to do with iracing? http://desmond.imageshack.us/Himg29/scaled.php?server=29&filename=winnerfriday.jpg&res=landing

John Douglas
September 1st, 2012 at 6:00 pm

SODA is good
still run it occasionally
it’s on my GPL server
: )

October 30th, 2012 at 3:29 pm

i would totaly buy into you guys if you facilitated dirt….why not be the ones to be the one company that actually did it for us dirt racers and reap the benefits…i know me and a lot of others are just dying for a good dirt sim….rfactor is just a teaser of what could possibly happen with the proper funding and support

October 30th, 2012 at 7:08 pm

dave do dirt many people i know complain because they just wanna se some action on the dirt, i would personally buy up everythingavailible for dirt even if it cost 25 dollars for a car or track i wouldnt mind because i race dirt modifieds and i love it and would love to race a simulation on it! please i will be forever in love with iracing if you add in dirt racing.

tyler hulmes
November 7th, 2012 at 7:44 pm

here here!

J Zimmerman
November 16th, 2012 at 10:18 pm

lets get dirty

jamie bullard
December 12th, 2012 at 2:02 am

If they got dirt i would delete my rfactor

June 23rd, 2013 at 3:43 am

Late Models is the most sought after and should be first……Eldora is a must…
rat bag developed great racing in their World of Outlaw Sprint car racing….use that for a base line……Awesome racing for a old game…..very realistic….

Tom Cerrato
July 20th, 2013 at 6:35 pm

it’s the tires, stupid

August 17th, 2013 at 7:07 pm

R factor and dirt track racing 2 have many followers but if you consider going to dirt think about what has killed the support for these to dirt sims. Changing car fikes and peeople having to cheat to win is the norm for them sim racers, so please find a way to keep the note padding of setups and car files from getting changed and make the track and even sport for all.

October 13th, 2013 at 5:02 pm

I searched iracer.com dirt track racing to see if anything pulled up. I would definitely become an iracer should they bring oval dirt racing into the mix. Modified, late models, and sprint cars on Eldora, Lucas oil speedway, etc. Sign me up!

August 25th, 2014 at 11:36 pm

My PC has been down for 3 years and miss Rfactor…because of dirt racing,,,,,the Organization of racing in rfactor sucks but at least its DIRTNATION!!!!!!!!!!! Im looking to get a new computer and buy RFACTOR….Did that say anything bout no dirt in iracing? My friend Scott Granberg Huge organizer of league racing in Iracing …still cant get me in iracing till i know theres Modifieds!!!!! on dirt!!!! good day!!!!

IMCA Lover
July 29th, 2015 at 1:03 pm

I have read some good stuff here. Certainly price bookmarking for revisiting. I wonder how so much attempt you put to make any such excellent informative web site.|


Quintin Rawlings
August 15th, 2015 at 11:52 am

Little did we know iRacing would be comin g out with dirt 6 years later

March 11th, 2017 at 2:24 pm

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