Thread:

The world is ending as we know it....

EFI in NASCAR

NASCAR takes 'really big step' with fuel injection - Jan 11, 2012 - NASCAR.COM

But here's the thing: NASCAR's common plenum manifold throws a curve to the engineers and tuners who might have EFI experience from other racing series.

"In that common plenum manifold, each cylinder is still talking to each other through the firing order sequence," Yates said. "And it does still pull fuel from one cylinder to the other, which is something that's unique to our sport and a challenge, but also an opportunity that other series don't see.

Interesting thing about efi in a single plane intake.

And just a couple months ago the first turbo EFI boat ran at Firebird too after all these years.

Bernoulli is turning over in his grave.

Originally Posted by steelcomp

Interesting thing about efi in a single plane intake.

Not too surprising considering the relatively short runner length, however, much easier to deal with using an O2 sensor and a laptop.

Hey, if Tom Compton ever wakes up and reads this, even the NHRA Pro Stock might follow suit in another decade provided we have manufacturers still making those type cars then.

Yup...

Originally Posted by The Doctor

Hey, if Tom Compton ever wakes up and reads this, even the NHRA Pro Stock might follow suit in another decade provided we have manufacturers still making those type cars then.

The idea that they were afraid of run away costs hurting the lesser funded teams fell apart long ago. Sportsman classes have switched over, if anything because it was cheaper in the long run.



The idea that the cross talk in the manifold pops up in the conversation is kind of funny. It happens with a carb as well. You would like to think that richening one hole without effecting the others would be simple. But not in a manifold that closely coupled.

So at this rate can we assume that DFI in either Nascar or the NHRA is 30 years away?

There may be an up side to them being so slow on the curve. When we are all driving plug ins, they will still be racing cars that actually make noise.

Originally Posted by gn7

The idea that they were afraid of run away costs hurting the lesser funded teams fell apart long ago. Sportsman classes have switched over, if anything because it was cheaper in the long run.



The idea that the cross talk in the manifold pops up in the conversation is kind of funny. It happens with a carb as well. You would like to think that richening one hole without effecting the others would be simple. But not in a manifold that closely coupled.

So at this rate can we assume that DFI in either Nascar or the NHRA is 30 years away?

There may be an up side to them being so slow on the curve. When we are all driving plug ins, they will still be racing cars that actually make noise.

He mentions that it does STILL pull fuel meaning that it always has with a carb and they were finding that EFI does also. Look how high the injectors are in the runner. We have experimented with that with good power results. The higher in the runner, the more likely to pull fuel from other cylinders. The way I read it, NASCAR and EFI is now, not 30 years.

Originally Posted by BDMarine

He mentions that it does STILL pull fuel meaning that it always has with a carb and they were finding that EFI does also. Look how high the injectors are in the runner. We have experimented with that with good power results. The higher in the runner, the more likely to pull fuel from other cylinders. The way I read it, NASCAR and EFI is now, not 30 years.

I posted another 30 years for DFI!

Originally Posted by gn7

The idea that they were afraid of run away costs hurting the lesser funded teams fell apart long ago. Sportsman classes have switched over, if anything because it was cheaper in the long run.



The idea that the cross talk in the manifold pops up in the conversation is kind of funny. It happens with a carb as well. You would like to think that richening one hole without effecting the others would be simple. But not in a manifold that closely coupled.

So at this rate can we assume that DFI in either Nascar or the NHRA is 30 years away?

There may be an up side to them being so slow on the curve. When we are all driving plug ins, they will still be racing cars that actually make noise.

It's far less of an issue with a carb. In the EFI intake, you have a good deal of the intake upper runners and the entire plenum that's air-only. You start cross-talking between air/fuel and air-only, it can get a little "confusing". With a carb, there's basically no where in the intake below the carb that isn;t an air/fuel mixture, so cross talking really doesn't have much of an effect...at least not like it will with EFI. This is part of why having the injectors higher in the runners works better.

Originally Posted by steelcomp

It's far less of an issue with a carb. In the EFI intake, you have a good deal of the intake upper runners and the entire plenum that's air-only. You start cross-talking between air/fuel and air-only, it can get a little "confusing". With a carb, there's basically no where in the intake below the carb that isn;t an air/fuel mixture, so cross talking really doesn't have much of an effect...at least not like it will with EFI. This is part of why having the injectors higher in the runners works better.

I think thats the point they were talking about. It is a air/fuel mix in the plenum, and I imagine it starts the second the engine fires. Worse and low Rs than high, but still there all the way thru the RPM band.

Originally Posted by steelcomp

It's far less of an issue with a carb. In the EFI intake, you have a good deal of the intake upper runners and the entire plenum that's air-only. You start cross-talking between air/fuel and air-only, it can get a little "confusing". With a carb, there's basically no where in the intake below the carb that isn;t an air/fuel mixture, so cross talking really doesn't have much of an effect...at least not like it will with EFI. This is part of why having the injectors higher in the runners works better.

I see the F1's put the injectors right outside of the runners,

Not really that new of an idea when you think about it.