Fuel Pressure / Why

I am looking forward to the answers already......
There is so much great experience on here.

My question is why is it not seen to be effective to run Fuel Pressure at say 200PSI ? would it not atomize better ?

Sorry if this is a basic question to ask for some , but Iam always interested in real world experience from racers and tuners.

Thanks Wayne

 

The reason I have discovered not to run pressures up that high is you tend to bend/twist pump shafts over time. As far a performance, I'm going to defer that to the more knowledgeable.

Corey

 

Well look at efi now. They used to have a very large pump and return line. Now you see most systems are no return line and much less psi. You have to turn that pump when your not using all the fuel needed at idle and climbing thru the rpms . That's what I gather out of It

 

Many good tuneups, that add fuel going down the track are setup to hit around 200 psi at the finish line.

 

Not in a roots? Screw motor ?

 

yes , i should have said.....roots blower deal

 

Hi Mike , thats just what i have been thinking...any more thoughts guys

 

Don Jackson makes a nozzle like your talking about
714 269 9645

 

I know there are 2 EFI nozzle designs one has a beautiful atomized cone pattern the other looks like a garden hose .in back to back dyno test there was no power difference. with a valve opening and closing 80 times a second and you have to get X amount of fuel in that cylinder in that time.

 

When I started looking into EFI and learning about batching, I started to understand that there was fuel flowing when the valve was closed (duh on me) just like our constant flow mechanical injection. If the valve is closed, it seems to me that the fuel is going to just puddle until the valve opens again. So the above statement where the pattern would not be that big of a deal makes sense. Maybe I'm missing something but the only time I would see that atomization would be possible is during the time the intake valve was open and the fuel would be mixed with the moving air.

 

The current efi on a super charged engine is using nozzle bodies we already use but with those electronic valves on the top of the blower to control it.

 

http://www.ragefuelsystems.us/

Anyone using the spraybar that is shown in the lower right corner of the webpage? I did an internet search and didn't see any other info out there besides the video. 80hp is a big claim, anyone have inside info on what type of nozzles the spray bar is superior to?

 

The spray bar works as advertised

 

If this were true we should see an increase in efficiency and power as we increase the fuel pressure for better atomization.

 

Since the the valve is closed more than it's open - a 280 duration cam has the valve open 78% of a revolution every other revolution, so the valve is only open 39% of the time. During the time when the valve is closed, the fuel's spraying in, the blower is cramming a fuel mixture that's likely not that atomized after going through the mixMaster - it seems like you're going to get pooling on the runner and the back of the valve no matter what your nozzle spray pattern looks like. I think that may be why turbo69 saw no difference between the spary patterns on the dyno.