Has anyone tried fuel injection?

Like the title states, has anyone tried it? With all of the technology in EFI, the large fuel injectors and the capability of running multi-injectors has anyone tried it and had any sucsess?
I am curious and just wanting to know, it sure works well on our Procharged combo!
Thanks in advance
AJ

 

well nhra don't allow it....must be manual

 

EFI would be fantastic if we were allowed to use it. All the variables that we 'attempt' to tune MFI for, to get the fuel curve just right is done very accurately and instantly. The toughest part would actually be programming the ECU, and that's not hard

We could (almost?) kiss goodbye to burnt up parts because the AF mixture would be spot on all the time. No pre-priming the engine for start up, no fuel shut-off, we wouldn't even need to worry about tuning each cylinder to get them all even. With the EGTs and CHTs telling the ECU what to do (closed loop) our tuning worries would be over. We could monitor what the fuel system is doing through the datalogger (in real time if we wanted to) and re-programme the ECU accordingly.

It would bring down the cost of racing while making more people competitive. Makes me wonder why the sanctioning bodies are against it...

 

Well now

If we all go to EFI with ECU to watch our EGTs and CHTs so our ECU knows what to do why dont we all just stay home in front of our computer and race online. Sure would be cheaper. Man and Machine the foundation of raceing right? Add in electronics and man tends to vanish into the background and the machine thinks on its own. I will pass. We run a mag kill switch and a wire to the tack DONE.

 

An ECU would never understand nitro tuning.

 

I think it would help for sure, but lets not forget most of the mixture problems result from dumping fuel into the blower to cool and seal it. If you were not dumping fuel into the blower I think it would be a lot easier to get the air distributed fairly evenly to the cylinders then pulse width MPFI would have an easy job of adding the correct amount of fuel to each cyl to correct for relativly small flow distribution problems, but with the fuel on top of the blower the pulse width would still be a band aid ( granted a good one ) for the huge mixture distribution problems. Don't forget the problems of fuel pooling, atomization, uneven heat etc. will confuse the hell out of the sensors the electronic injection uses to determine pulse width.

I feel this is why the electronic injection is so sucessful on the centifugal and turbo deals where you are only dealing with compressed air. An idea I have been tossing around in my head is a lot of the twin screw superchargers do not require fuel to be added for lube or seal. I think in an unlimited ( by rules ) catagory mounting one of these in front of the engine or in the passenger side rear (shaft driven) on a door car would help get the blower out of the wind and allow an intercooler and electronic injection to reach its full potential, of course you would have to worry about the tech aspect of mounting it in the interior but thats a whole different topic

Richard Gavle

 

Agreed Will,

So far its only the Eatons and the smaller Whipples that are set up to run without fuel in the supercharger, Hopefully in the future they will offer larger units designed to run dry, In the mean time the Whipple 305AX supplies almost 3500 cfm and up to 30 lbs of boost with 77% adiabatic effinciency (very easy to intercool). So it suffers the same problem as the Procharger F3r (4000 cfm at 45lbs) its not quite big enough flow and pressure wise to be used in a single configuration. The thing I like about the Whipple though is that its boost is linear in nature making the fuel curve as well as the power output a lot easier to predict/manage.

Someone will eventually try two side by side on a big displacement engine or an f3r feeding a 305ax. Several people have already tried side by side F2s with varying degrees of sucess its just a matter of time in my book before someone is successful in combining twin screws and intercooling or centrifugal and twin screw and making big power and having a nice happy engine.

In the mean time of course there is the tried and true D rotor in standard configuration, but if you want to be a pioneer there are a lot of avenues yet unexplored. Of course I guess you have to keep in mind a lot of pioneers wind up being eatin by savages

Richard Gavle

 

just a question

What about a combo of both? Run MFI into the hat for the blower and direct port injection with the EFI. If you are monitoring cht/egt's with an ECU couldn't the adjustments be made within the EFI system to fatten/richen each hole as needed? Seems if you are looking for the right AFR that the EFI would be blind to what's happening upstream from it; it would "read" what the motor wants and adjust to it.

 

Moparious......you are soooooo right..Dave

 

James a combo could work but I doubt it,

I don't think the base map could be kept close enough (due to the varying amounts of fuel fed through the blower and the cylinder to cylinder variation at different RPM) to allow the ox sensors, throttle pos sensors, boost sensors, ect to make large and intelligent enough changes to allow it to function correctly.

I think this is the problem a lot of people have when they try to use electronic injection in a conventional setup, you need to have the fuel injectors in the middle of their parameters and the base map close to correct to minimize the corrections (and maximize the ability to create change) the ECU needs to make. Of course alcohol sensors and ECU capabilities keep getting better and better but I feel the sensors are a long way from being able read the values of a blown hat injected engine and the ECU would be unable to compensate for the amount of fuel correction you would want to make on the typical roots/screw blown engine, I could be wrong of course this is just my best guess on the subject.

Richard Gavle

 

Efi

I have thought about EFI on a top alcohol engine and I think a good way to start would be the following combination.
You run the tank, pump, distribution blocks, hat and intake nozzles as normal. The part were the computer comes in is instead of having bypasses, timers etc you have just one big return to the tank that is controlled by a computer controlled valve so that the fuel pressure is infinately variable . Simple enough to be robust, uses the majority of the existing equipment and MUCH more tunable than the current pressure and time related methods.
Jim

 

Theoretically sounds like a good start, next development I suppose could be to add the port nozzles to the EFI as suggested above.

That said I prefer the simplicity of a mag ignited MFI system - as said above the only electronics needed is a kill switch.

 

Those Turbocharged Alcohol guys are running fuel injection with port nozzles all the time... I think you could make some serious safe horsepower! Some of those turbo cars are making over 3000 horsepower.

 

Have a friend who has a FAST efi that appears to be large enough for my stuff. He talked about letting us use it on the dyno. The rules don't let us run it but I thought it would save the amount of dyno runs as you wouldn't to continue to tune the fuel system for every experimental part you tried.

Another friend has a turboed SBC with the Accel efi and I'm surprised you can't simply enter in an AFR. Why all the maps, why can't they be told to run such and such AFR and thats what they do, regardless of TPS or boost or RPM??

560Jim, we've talked about similiar setups, like an IAC in the return line which is being told what to do via an input from a OX sensor

 

Because, as you know, no two engines are the same. Different engines have different AFR requirements at different RPMs, throttle settings, load, etc. That's the hardest part of setting up EFI, just like MFI. Except, once you've got it dialed in to your engine, it'll do the rest...