Hi Speed

Should the hi speed be connected to the port nozzels or hat nozzels?

 

Question for Mike

Hi Mike, I have known people to say to run the hi-speed off the port nozzles before but have never heard a satisfactory explaination as to why. My novice thoughts on the subject are it doesnt matter if it is the port line or the hat line as they are both connected by a large passage inside the B/V and therefore reducing pressure in one line directly affects the pressure in the other.
Is there something I am missing here and can you explain it in simple language that I can understand ?
Also on the same subject, I have also been told to place the hi-speed before the barrel valve but the only difference I can think of there is that it will then open during the burnout at part throttle whereas it probably wont after the B/V.
Is there something else going on here as well ?
When a hi-speed opens and drops system pressure, wont it drop right throughout the system ?
Regards.
Jim

 

Thanks for the reply Mike. With the pressure difference the hi-speed sees before and after the B/V, is that an indication there is significant restriction within the barrel valve ? Is the flow difference much different between the billet and K-style B/Vs ? Anyone else got anything to add ?
Cheers, Jim

 

Do you mean the cube style valve?

If so, the cube style valve is best suited to lower HP blown or NA engines.

EDB

 

Explain this

When only changing from a cube BV to a K BV will the pressure increase/decrease to ports & hats? And would it now be necessary to change main pill size because of the increase/decrease in pressure if all other things remain the same? And now would the HS would come in earlier/later due to the pressure changes?

 

I've not done that BV change yet, but...
The K style will have more psi in the outlet ports. So more psi at the nozzles. I don't know how much.

Why does Enderle push to go to the K style on the bigger (990's, 1100's, 1200's, etc) GPM setups?

 

i was told to put the high speed in the port line.reason being you don't want to take away fuel going through the blower as that is what lubes and seals it.the high speed probably takes away too little fuel to make a big difference but it made sense to me.

 

Not as much as if you took it out the hat.

 

No, they're the same. It doesn't matter where you put the high-speed check valve, the "leak" you're introducing when it opens causes a pressure drop in the entire system.

Instead of thinking of it as "taking fuel away", think of it as taking pressure away from the system which causes less fuel to fall out of all the nozzles into the motor. Just like when your wife flushes the toilet when you're in the shower. All the faucets in the house see diminished flow because of the reduced pressure the open toilet valve causes.

Same with the main pill...one perspective is that you're using it to take fuel away and return it to the tank. I prefer to think of it as an adjustable leak that sets the system pressure. You're regulating how much fuel falls out of the nozzles by changing that pressure.

Spud
www.fuelinjectionent.com

 

Spud, what if you took the hi-speed and set it to leak say to 60 lb,s with a 080 jet and had it return to two more nozzels (same ariea as the 080 jet) in the hat that don't get any fuel till the hi-speed kicks in, (the hi-speed goes directly to the two nozzels) do you think it would help cool the blower and the air going into the blower and add more power?

 

eli, if you route the fuel to go back to the blower it would then be introduced into the engine; fattening it up. the hi-speed is used to take it away completely from the engine.

 

I understand that, my tough was with a roots blower, after a certain point it's just pumping hot air,the idea is to introduce cold alky to the rotter's and cool the charge, it's just an idea, i have no idea if it would work, thats why I asked Spud if it would. He's one of them guru's on the fuel systems, I'm trying not to get Alzheimer's, got to keep the mind working. besides fly fishing and golfing, racing is the only thing i know how to do, and i'm always thinking about new ideas, as should everyone.

 

Hi speed to hat

Hi Eli, is what you are suggesting to alter the ratio of fuel under and over the blower as speed and boost rise ? An interesting idea. If you were to do that you wouldnt need a jet in the "hispeed" as the nozzles would control the flow. I suspect that in addition to your idea you would still need to take away some fuel at the top end for maximum power. Such outside the square thinking should stave off old age for a while LOL.
Jim

 

Never really worked on a rootes to run really fast however based on what eli has asked leads me to ask a question.

What is the point when running to much fuel through the blower begins to cost more power than the benifit of cooling.

We run screw blowers and run just enought through the hat to keep the rotors happy and use the ports to create the magic.

thanks

clarky

 

Dude, ( still trying to stay young even in speech hehehe) Thats the whole point, a screw blower the more you spin it the more boost it makes,in turn the more fuel you need and you make more power, A roots the more you spin it the more HEAT it makes, in turn making the fuel hot (less power) so cooling the hat area would make more power?? So Who's on first, Whats on second, I don't know, third base! Come on Guys, some body can try this,All it could do is not work it wont hurt your motor (unless you hydraulic it) if it works you just tell me no one else, and your car went faster, I'm just trying to make the roots work like a screw, now do you get the idea (Schmedley ???? ya Im talking to you)

 

If you could run all the fuel through the hat and get even distribution would be ideal. The fuel would help seal the blower and make more boost, no matter what blower you had.When PSI's first came out we were told that one needed little to almost no fuel through the hat, but now to make them work almost half of the fuel goes through the hat nozzles.