Where does the difference in car performance come from?

[zako85]

I often hear on TV during IndyCar race that such and such cars are very fast today. Where does this performance difference come from? Is this from engine map tuning, suspension or something else? What can a more affluent team do to beat other cars?

[NickFalzone]

According to AnthonyVOP, it is from Honda supplying their favorite teams with better engines. According to the rest of us, it is aero tuning and possibly some trick parts (aero and otherwise) that get some "spec" cars faster than the others. As the unspoken rule goes, if you're not caught, you're not cheating.

[EagleEye]

I often hear on TV during IndyCar race that such and such cars are very fast today. Where does this performance difference come from? Is this from engine map tuning, suspension or something else? What can a more affluent team do to beat other cars?


Spec engines, spec chassis, spec tires, so there really should be a 26 tie for first. But, that is far from the case since the teams that have money can usually find a way to move forward.

Here are just some of the ways.

Lighter chassis. The top teams spend quite a bit of time, removing weight from the car. But wait a tic, they all have to be the same weight right? Right. But, by removing weight, they can then use ballast to put the weight in ideal spots to improve and enhance handling.

Aero Tweaks. The top teams can add little aero bits and even brake ducts to help create downforce. Using the right size brake ducts allow you to run less wing angle, which give the car a faster top speed. Next time you are at the track, get a garage or pit pass. Walk down and check take pictures of the Coyne/HVM car. Front wing, front of the sidepod, mirrors, brake ducts, shutters, stingers, rear wing, engine cover. Then do the same with a Penske and/or Ganassi car. Look at each closely and you will see some subtle differences.

People. While the top teams were racing in Toronto, Jr. Engineers on the road or back at the shop were already completing computer simulations for Edmonton to enhance setups, and come up with directions to go in set up changes in order to improve lap time. That is typically why you usually see the usual suspects at the top of the speed charts throughout the season. Sure, a team can stumble on a good setup, and have a good weekend, but over the long haul the top teams usually lead due to power in numbers.

People 2. Team A pays you $100K/year plus X% for winnings, covers your travel (your drive to most events) and you share a room with a guy named “Stinky” while you engineer their car. You have no medical coverage, and only work from March through October. Team B pays you $300K/year, X% of winnings; you get your own room and can fly out on the corporate jet. You have medical and dental, a company car, and you work year round. The better teams, can get the better people.

Shaker rig testing. The top teams have done quite a bit of shaker rig testing, which is basically testing the chassis dynamics on a chassis dyno. Each chassis has its own spring rate, which work best with specific settings. While close, no two cars are the same. By profiling a car’s unique characteristics, you can better find a setup that not only suits the driver and circuit, but also that particular car.
Diff testing. Putting power to the ground and getting a good launch off the corner is the secret to going fast. While amateurs talk of “late braking” the key to good lap times is exit speed. If the diff locks too soon, the car can oversteer. If it locks too late, you can lose time due to wheel spin. A lot of time is spent working on the dif ramps, and when and how they lock up.

Gears. Some teams spend quite a bit of time selecting the perfect gear ratios to match their particular set up. Some teams use higher quality parts, which improve efficiency. Some run special gear oils in order to reduce drag in the box.

Engines. All engines are created equal. All people are the same color, and have the same IQ. Well, no on both counts. While teams are supposed to choose from a pool, there can be a nudge-nudge wink-wink with those who dole out the engines. Here is a low mileage Honda engine, here, that is just as good as this “wink” “wink” one. Since all engines are spend time on a dyno, some teams can get info on which engines have an edge. 1% more power is good enough to get you out of the corner quicker than the next guy.

Setup history. The top teams have a history of setups, some dating back to the early 80’s! While the cars have changed, and setups have changed, for many of the tracks the direction you go for improving the lap times can be similar. You basically have a better idea of which way to go to improve lap times.

There is a LOT more, but this is a good start.

[SoCalPVguy]

These are "spec" cars and at least when they were new anyway, they were all equal at one time, a long time ago... Two components of course: engine and chassis. Engines should be equal with factory mapping and performance. However we all know some teams ... cough cough (*penske/ganassi*) may be getting some 'factory' engine home cooking not available to the smaller teams). Given similar engine performance, speed is derived from chassis set up. The trick is to 'catch lightening in a bottle' in the set up as the track conditions (surface grip, oiliness, amount of marbles), weather, barometric pressure, track temperate, all vary minute by minute. Set ups include front suspension (toe-in, camber, thrust), rear suspension angle, and all infinite combination of front and rear wing settings that vary downforce. The quickest set up for any condition is just the right set up at that moment and not only changes race to race but minute to minute. Given that no two old Dallara tubs are the same through wreckage and repairs, the effects of aero and suspension vary from car to car also... Its all about feedback from driver, teleported on board data acquisition, and interpreted changes. One guy can be fast one day and slow the next, same for week to week. The fact that the same five cars: 2x Ganassi and 3xPenske are the fastest week in and week out indicate two things to me: They are the best at data interpretation and resulting alterations, or there is more than meets the eye in the so called equal 'factory' equipment than what the smaller teams get.

[Mark in Oshawa]

Better teams have better resources. No favouritism from Honda, Dallara or the IRL is needed. A team like Penske or Ganassi has the better people and that is usually all it takes.

EE has an excellent list of reasons how this all manifests itself, but if you have the money and people, you can massage your piece of turd faster than HVM or Dale Coyne. It is a credit to Coyne and HVM they get some of the results they do....

You can see ample evidence in just one engineer. Before Tag's lost the guy who gave him the great early results of this year and the pole at Indy, he was flying..now..back to mid pack where he was last year...and that is if he does everything right..

[Lousada]

These are "spec" cars and at least when they were new anyway, they were all equal at one time, a long time ago...

They were never intended as spec cars. Way back when they were build in a competitive enviroment. They became spec by default because they pushed the competition out. Somewhere along the line (2008 I think) they 'froze' the development, creating the 'spec' series. Except of course that some teams like Penske/Ganassi had 5 years of experience with developing the chassis to the limit, while others who moved to Dallara later now had a much harder time to develop.

[dataman1]

One more point. The Dallara chassis spring rate EE speaks of can very vastly with age of the chassis, number of crashes it has seen, etc. A five year old tub and a new tub with identical bolt on equipment, same setup, same engineer and same driver on the same track will not perform the same. If you could see the carbon fiber in a microscope after several crashes you will find cracks, much like tapping on an egg shell. That loosens the chassis to flex more. Sometimes that flex is good for certain tracks but it a real pain for engineers on an big oval where it will flex in one direction on turn one and another in turn four.

[Lee Roy]

Thanks Eagle Eye. That was a straighforward and rational explanation. Something not often found on racing forums.

[chuck34]

One more point. The Dallara chassis spring rate EE speaks of can very vastly with age of the chassis, number of crashes it has seen, etc. A five year old tub and a new tub with identical bolt on equipment, same setup, same engineer and same driver on the same track will not perform the same. If you could see the carbon fiber in a microscope after several crashes you will find cracks, much like tapping on an egg shell. That loosens the chassis to flex more. Sometimes that flex is good for certain tracks but it a real pain for engineers on an big oval where it will flex in one direction on turn one and another in turn four.

It doesn't even have to be crashed. Miles will "soften" a carbon tub significantly on it's own. A new chassis will be stiffer than a race run chassis even without wrecks, etc.

Eagle Eye pretty well lays out the basics. If anyone wants more details than that, you might start thinking about investing in some books.