NASCAR and EFI

Jan. 1, 2020
The Daytona 500 is arguably the most famous race on Earth.

The Daytona 500 is arguably the most famous race on Earth. It marks the first entry into the NASCAR history books, when the first race sanctioned by the newly formed National Association for Stock Car Racing was held on the beach course on Feb. 15, 1948.

NASCAR’s history has its roots in the Prohibition era. Runners, the guys who moved homemade hooch, also fondly known as moonshine, hotrodded their cars so they could evade the federal agents that were trying to stop the illegal transport. Remember Burt Reynolds’ portrayal of the character “Gator McKlusky”? The runners built their reputations on their ability to outsmart, and outdrive, the law — and often held informal races to see who among them was the fastest.

By the end of the 1940s, these contests had become a roughly organized sport, largely due to the efforts of Bill France Sr. His work resulted in the birth of NASCAR on Dec. 14, 1947.

This year at the 2012 running of the Daytona 500, another entry was made into both the NASCAR and Daytona history books as fans witnessed the end of the carbureted engine, and the debut of electronic fuel injection (EFI) in the Cup series. Motor Age recently interviewed NASCAR Manager of R&D Mike Fisher about the change.

MA: What prompted the move to fuel injection?

Fisher: The short and simple answer to that is, it was time. The carbureted engine has served us well for our entire 60-year-plus history. We started to get some pretty strong feedback from the manufacturers that are involved in the sport — Dodge, Ford, Toyota and General Motors. They wanted to see a little more relevancy in the vehicles themselves.

We started that with the look of the new Nationwide cars, going back in a direction that gives some more identity for those specific model vehicles — you know, the Charger, the Mustang — kind of being at the forefront of that. The response was so positive they told us they’d like to keep going in that direction and do some things in the Cup series. They wanted to do it with the powertrain, and our response to that was, yes, it’s probably time to make the move to fuel injection on the race cars.

MA: Are there any specific rule changes that you could highlight related to this move?

Fisher: There’s a whole bunch of them, and it might be a little challenging to go through each and every one of them. We have some spec components that we will mandate that have to be used; there are other components that the teams are free to source. Pretty much everything that relates to this system, from the fuel tank and fuel pumps all the way up to the throttle body and the intake manifold, have to be approved by us. Even if we don’t have any specific rules or mandates around the parts, the teams all know and are familiar enough with our culture that they know they are going to have to show it to us, to make sure we’re all right with it so we’re not surprised with anything at the race track.

MA: I saw the press release from Bosch talking about their involvement with the move to fuel injection, and understand they will be the mandated (or spec) supplier of the oxygen sensors the new cars will use. What other mandated suppliers can you tell us about?

Fisher: Yes, Bosch is the spec supplier of the lambda sensors, and every team will be required to use those spec components. The ECU (engine control unit) itself is coming from McLaren/Freescale, and every team will be required to buy that from them. The throttle body will come from Holley, and again, that is a spec component — one part number, everybody has to buy it, they are not allowed to change it.

There is a specification for the fuel injectors themselves that any manufacturer is free to submit a component for approval. (Editor’s Note: At the time of this interview, Bosch was the only manufacturer to do so.) McLaren has provided the schematic for the wiring harness, but the teams are free to source the wiring harness construction itself to anybody they choose, or they can build it in-house. It has to be built to the spec and submitted to us for final approval.

From a sensor standpoint, the crankshaft sensors (two are mandated for redundancy) have to come from McLaren, but the rest of the sensors can be sourced as long as they have been submitted to NASCAR for approval.

MA: Is fuel injection going to be added to existing engine designs, or will we be seeing brand-new configurations?

Fisher: That was one of the challenges we struggled with in the introduction of this move, knowing the current economic times in our country — and to a smaller scale, within our sport — that this was not a good time to try and push a big change through. We tried to minimize the impact of it as much as we could. So we are not allowing any cylinder head modifications, very minimal intake manifold modifications. We didn’t allow them to change the general architecture or shape of the manifold, other than the mounting of the injectors. The only real changes to the engine are from the intake manifold up.

MA: So we’re looking at the same powerplant, just a little more modernized?

Fisher: Yeah, we don’t want to increase the power of the engine. The whole system has kind of been designed around keeping the power roughly the same. Even to the extent that we reduced the size of the throttle body (compared to the carburetors we had) to offset the small gain in horsepower gained from the optimization of EFI.

MA: Tell us a bit about the actual EFI system itself. Will this be a mass airflow system or a speed-density system?

Fisher: The teams actually have a choice of two strategies. One is speed density; there will be a MAP (manifold absolute pressure) sensor they will be able to utilize. The other is an “alphaN,” which is basically a fuel map that ties rpm and throttle position together. We do control the size of the maps and the adjustment ranges that the teams can utilize for both fuel and ignition (a coil-on-plug system, also controlled through the ECU).

MA: What companies were involved in the original R&D?

Fisher: We actually started talking to the race teams themselves in late 2009 about the change — how we should approach it, that type of thing. 2010 was pretty much spent going through the sourcing process. We actually wrote a specification internally here at NASCAR and sent it out to nine or 10 different suppliers of all different sizes and geographical locations. We sent it out to some big companies, like Bosch, McLaren and Magneti Marelli, and some smaller ones like Holley and Edelbrock. We took a pretty good diagonal slice of a lot of different companies with a lot of different capabilities before we made our final selections.

MA: Will the EFI cars run all the various tracks, or will it be limited to type of track?

Fisher: EFI will be in the Cup series only, all tracks, all races in 2012.

MA: Our readers are automotive repair professionals, and many are avid racers themselves. What would you like to share specifically with them?

Fisher: We had an example of this engine out at SEMA this past November. If you look at the location of the injectors, they are not in an ideal position for power and emissions. It is a multi-port system, kind of a mid-’80s technology. But because we didn’t allow any other changes to the cylinder heads or anything like that, and based on the way the current cylinder heads are designed, if we had placed the injector down at the end of the (intake) runner just above the valve, some manufacturers would have had a pretty significant power advantage based on their valve position.

So if you look at our injector, we basically positioned about halfway or so up the runner. Any expert would take a look at that and ask, “Who decided to put the injector here?” There is a rationale for that, and one thing our competitors expect from us is to be able to officiate the sport and ensure that no one has a significant advantage over another. A lot of what drove that injector placement, and the spray angle (which is straight down and not angled to go down the runner)… there’s some things about the system that if you were designing a fuel injection system from scratch, you wouldn’t do it the way we did it. But again, our goal is to maintain that horsepower parity.

MA: I’m sure another common question that comes up is, how will NASCAR keep people from cheating the system?

Fisher: A big part of the reason we chose McLaren as the spec ECU supplier is that they are the spec ECU supplier for Formula One. They have a great deal of experience working with sanctioning bodies, they know what being a spec supplier means, they know what teams are going to try, how they may try to manipulate the systems. They have some very sophisticated software and hardware tools within that ECU to prevent that kind of thing.

The first step is to try and prevent the teams from violating the rules. The second step, if somebody is able to violate the rules, in this case if they get in and start messing with the software, is to be able to tell that they have done that. If you can’t stop them, you’ve got to be able to catch them. The third element is the fines and penalties that happen when you do get caught.

MA: Why multiport? Why not go straight to gasoline direct injection (GDI)?

Fisher: This move is the foundation for future changes along this same line. When this is executed, and we get comfortable with the officiating process behind it and our ability to mange it within our sport, then taking the next step and allowing changes to cylinder heads to implement gasoline direct injection, or any other of those types of technologies going forward, will really become a little bit cleaner and a little bit easier to execute because we will have the experience. It’s not the technology itself that’s a big deal (with the current change); it’s us putting it into our racing environment and meeting the expectations of our teams and our fans.

MA: Any closing comments you’d like to offer?

Fisher: We’re certainly not blowing the horn too loudly, because fuel injection is nothing new. Our particular application of it is nothing new, but to make a change like this on the scale that we are trying to do it on was not a small undertaking. We think we’ve got a lot of it figured out, and we’re sure we’re going to learn some things going forward. But we can do this, and execute it cleanly while still providing the fans with some great racing.

MA: Thanks, Mike, for taking the time to hang out with Motor Age!

Sponsored Recommendations

Access Carside OEM Repair Data with MOTOR TruSpeed

Now available on all Autel MaxiSYS Ultra Series tools, MOTOR TruSpeed Repair delivers expanded OEM service and repair data within days of being published by

ADAS Case Study: From 10 Calibrations a Month to Over 10 A Day

Originally published by Vehicle Service Pros, March 26, 2024

Autel MaxiTPMS TS900: 3-in-1 TPMS Tablet

Originally published by Tire Review, April 4, 2024

Ask The Expert: The Basics & Benefits of Bringing ADAS Calibrations In-house

Originally published by Vehicle Service Pros, March 26, 2024

Voice Your Opinion!

To join the conversation, and become an exclusive member of Vehicle Service Pros, create an account today!