engine tuning would be done by electrical engineers, performance would increase and a Pandora’s box will open because the computers could add traction control, abs among many other "electrical aids"
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It would increase costs, making it even more difficult for small teams to survive. And it would make it MUCH more difficult for NASCAR to regulate.

There would be no positive consequences, other than a slight improvement in fuel efficiency. Which is why it’s unlikely to happen.
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The costs would jump for every team and the teams with the big bucks would have an advantage.

Cheating would become invisibly hidden in the CPU. I assume you are talking about Electronic Fuel Injection. Mechanical FI would be a step in the wrong technological direction.

The speeds would jump except on the resrtictor tracks which would be run flat out anyway and then the EFI advantage would be nullified.

NASCAR wants all the cars to be the same so they can race the drivers, not the cars. As it is they all run a suspension from a 60′s GM truck in the back, over head valve engines with carburetors. 15 inch wheels and identical bodies. Your street car is more sophisticated. It is spec racing. I still watch it every race though.
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Instead of adjusting on a carburetor, the engine guys would plug in a laptop.
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they couldn’t regulate the engine horsepower output, with a restrictor plate.
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All the Fuel Pumps would be Electronic for 1 thing and Fuel Pressure Would Be Regulated by a Chip and the Next thing you would have was Teams using Illegal chips!!!!!
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They would less gas and cause less pollution, which is a no no in the US.
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NASCAR uses carburetors because they can be regulated.
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Bite your tongue. It would throw out 50+ years of engine R+D.
The current fuel pumps run off of a cable and only spin if the engine is running. Fuel Injection requires 30 to 60 PSI so electric pumps would have to be used. But how do you shut the pump off so it wont pump the fuel cell dry and onto the ground in the event of a crash and the fuel line is split and the driver is unconscious? A Ford type inertia switch won’t work. There’s to much banging around in Nascar and they would be popping off all the time.
Nascar would have to hire new and train current tech inspectors.
Instead of a GO/NO GO gauge, inspectors would have to flow test each and every injector for proper size.
Nascar would have to ‘hand out’ there own chip’s just before each race.
Inspection times would nearly double.
The teams would have to spend millions on new R+D and training.
It would just be a nightmare. I could write pages on why it would be a huge mistake.
AFTER ALL OF THAT, Nascar would just slow the cars to 200 mph anyway!!! That would be the easy part. They could still use some type of restrictor plate. But there’s no point.

Think of it this way. The ONLY electronic piece of equipment Nascar uses now is the MSD ignition control box and they run 2 of them in case one goes out during the race!!! And they do go out.

I could see it now, "What happened Jeff"? Jeff–"Well I got a glitch in my Throttle Position Sensor and lost all power".
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My forte’ is fuel injection driveability and diagnostics so i’m NOT one of those ‘Fuel Injection sucks’ guys by any means.

the performance on the track would be a whole lot better but the cheating issues would be such a problem becuase you can tweak them ever so slighty and it will make such a differecne and they could not catch you.
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