Sprint Injection on Late Models

[hardracer32]

Is there a reason why this wouldn't work? Everybody keeps talking about the future of racing being EFI but I can't figure out why we couldn't run mechanical fuel injection like sprint cars. Would it not be just as effective? I think it would be better because you eliminate the possiblity of teams cheating up electronics at a ridiculous cost to conceal.

I'm just thinking out loud here but I would love to hear some opinions from people who have experience or knowledge of how the sprint injection sytems work.

I just don't feel like EFI has a place in certain areas of racing. I am all for advancement and technology that will make racing more enviromentally friendly and all that but I think we should give some serious thought as to the type of tech that we let into our sport.

[Matt49]

I'd say the main reason nobody has messed with it is because it's against the rules. I've read a lot of rule books and I've yet to see one for Late Models that didn't say that the motor has to be "naturally aspirated". They usually go on to say, in plain English, "no fuel injection".

[vms]

Its a mechanical fuel injection with single port injections. Most classes give some kind of spec carb. I don't know if there is a difference on the mechanical fuel injection they run on hot rods and the sprint car but one is for gas and other for methanol. But i would sure love to see on a dyno.

But the think the makes sprint engine unique is they dont have starts, or fans plus the power steering is run of the back of the cam same with the fuel pump. Its just raw power.

[Matt49]

Where the fuel pump and power steering pump is mounted doesn't have any effect on power output. Google "law of conservation of energy" and get a quick physics lesson. The only reason they mount everything to the back is to assist in getting proper weight distribution. Lack of a starter is also not a "power generating" enhancement, it just means they don't have to carry the extra weight. Sprint cars are faster than Late Models because of a higher HP/weight ratio. To surmise that it is "raw power" is to not understand what is going on.

[talclipse]

Just to clarify, "naturally aspirated" does has nothing to do with fuel injection. This simply means that the motor uses atmospheric pressure. The alternative to natural aspiration would be forced induction. There are carburated and EFI forced induction engines and viceaversa. Google naturally aspirated.

In my opinion where the LM rules eliminate fuel injection is by mandating a single four barrel carburetor.

[fast46]

We ran kinsler fuel injection on our "outlaw" latemodel through most of the 90's, on alcohol. Didnt really have any problems, except we usually had to prime with gas to get it started when it was cold, otherwise it was pretty easy to flood . once it was warmed up it started just like being on a carb. You had to get used to looking around the stacks coming through the hood!

[Matt49]

Just to clarify, "naturally aspirated" does has nothing to do with fuel injection. This simply means that the motor uses atmospheric pressure. The alternative to natural aspiration would be forced induction. There are carburated and EFI forced induction engines and viceaversa. Google naturally aspirated.

In my opinion where the LM rules eliminate fuel injection is by mandating a single four barrel carburetor.

Good call.

[dirty white boy]

been a few articles bout the benefits of efi on a late model in circle track mag recently,..even ran one against carb'd late models,...hot rod been doing hp articles on efi for years,....yeah its a lil costly but speed cost how fast can you afford to go!!...ant no way a carb can out do a good efi with a computer tune up on it,..these aftermarket stand alone efi computers can figure air to fuel rato's an change them as needed within mila-seconds,..cuss it now but when you get use to it,..i assure you,..youll love it!!!

[MasterSbilt_Racer]

been a few articles bout the benefits of efi on a late model in circle track mag recently,..even ran one against carb'd late models,...hot rod been doing hp articles on efi for years,....yeah its a lil costly but speed cost how fast can you afford to go!!...ant no way a carb can out do a good efi with a computer tune up on it,..these aftermarket stand alone efi computers can figure air to fuel rato's an change them as needed within mila-seconds,..cuss it now but when you get use to it,..i assure you,..youll love it!!!

You are 100% correct, but it is only as good as the info the sensors are feeding to it.

[F22 RAPTOR]

Is there a reason why this wouldn't work? Everybody keeps talking about the future of racing being EFI but I can't figure out why we couldn't run mechanical fuel injection like sprint cars. Would it not be just as effective? I think it would be better because you eliminate the possiblity of teams cheating up electronics at a ridiculous cost to conceal.

I'm just thinking out loud here but I would love to hear some opinions from people who have experience or knowledge of how the sprint injection sytems work.

I just don't feel like EFI has a place in certain areas of racing. I am all for advancement and technology that will make racing more enviromentally friendly and all that but I think we should give some serious thought as to the type of tech that we let into our sport.

Really I don't see a point in going with fuel injection, if your not gonna go EFI. What I mean is, the whole point in going with EFI, is better control of emissions and fuel efficiency. If you went mechanical it would be almost strictly a performance enhancement with a minimal gain in fuel efficiency, but in most cases now we have more HP than we can use. I mean Ronnie Johnson keeps on beating the open cars now with a 540HP engine in the right conditions. I understand wanting to keep out electronics since it opens the door to other things we don't want, like "TC", but it sounds like if we want our sport to grow we may want to consider EFI in some form, but I'm leery of it too... JMO

[hardracer32]

Really I don't see a point in going with fuel injection, if your not gonna go EFI. What I mean is, the whole point in going with EFI, is better control of emissions and fuel efficiency. If you went mechanical it would be almost strictly a performance enhancement with a minimal gain in fuel efficiency, but in most cases now we have more HP than we can use. I mean Ronnie Johnson keeps on beating the open cars now with a 540HP engine in the right conditions. I understand wanting to keep out electronics since it opens the door to other things we don't want, like "TC", but it sounds like if we want our sport to grow we may want to consider EFI in some form, but I'm leery of it too... JMO

You are the first person to actually address the question I asked. I never said anything about rules. I know the rules concerning carb and fuel injection and pretty much everything else. My question is in regards to the practicality of mechanical injection vs. EFI on Late Models.

Now that we have that established, let's discuss a little further. ;)

[F22 RAPTOR]

Is there a reason why this wouldn't work?

No it would work, it's just more expensive and can be ornery at times.


Everybody keeps talking about the future of racing being EFI but I can't figure out why we couldn't run mechanical fuel injection like sprint cars. Would it not be just as effective?

We could run mechanical, but it wouldn't really be much of a move in the so called, "Green" direction. It would boost power and probably performance, but emission and efficiency benefits would be minimal. Now don't get me wrong, I'm no, Tree hugging/Global warming/Climate change/Green freak, but I do think it would be beneficial to the sport if we had a little more in common with what is being manufactured, at least from a technological standpoint.


I think it would be better because you eliminate the possiblity of teams cheating up electronics at a ridiculous cost to conceal.

I share your fears about people manipulating the electronics, but why not let them be adjustable and not worry with it. They have sealed units now that are tamper resistant, but you could make them somewhat tunable I think and it would be no different than tuning your carb. They just need to make sure you can't sneak in TC.


I'm just thinking out loud here but I would love to hear some opinions from people who have experience or knowledge of how the sprint injection sytems work.

I have no direct knowledge of sprint/mechanical injection systems. I've only ever seen them on a late model in pictures, but I do know they are pricey in comparison to carbs.


I just don't feel like EFI has a place in certain areas of racing. I am all for advancement and technology that will make racing more enviromentally friendly and all that but I think we should give some serious thought as to the type of tech that we let into our sport.

I agree somewhat and share your opinion on being careful of what tech we let in or how its implemented, I mean I wouldn't want to legislate carb companies out in one fell swoop, but I think we could at least look into whats possible without going bananas. JMO

[racin6mod]

I remember seeing an artical a few years back in one of the first dirt latemodel magazines.the latemodels out in the north west had the sprint car type fuel injection.