After a discussion with another member on MFI and pressure. Got to wondering what other run for pressure. Not saying you set it up for one pressure and worked from there. Just what pressure your system operates at. Not that anyone is better than the other.

If replying and know the following please include.
Pressure at____ rpm
Pump flow
which pump
nozzles
style BV( cube VS. K style can be 50 lbs)
What part of system are you getting pressure.
Not asking for changing my stuff just a discussion of what you might run at.

On all of my MFI stuff, I try to stay around 150 psi at 8000 rpm or 4000 pump. My pumps are oversized in some views at 7 gpm, but what I have always used. That is non blown of course, Seeing that I return over half to tank they maybe right. I do have room to adjust if changine flow requirements. Pressure is because I feel better atomization . Plus all of my jet and nozzle flow sheets are based on 150 psi. Makes it easier for me to figure gpm to engine and bypass. Not saying a low-pressure system does not work at all.

This message has been edited. Last edited by: wideopen231,

You just don’t learn.

Nearly 1 month ago you posted this

https://drr.infopop.cc/eve/foru...0760912/m/4027066007

Resulting in no replies and now this that hasn’t gotten reply in 12 hours.

FYI, your “stuff” isn’t on a bracket car nor are you a bracket racer!

Another of the many

quote:

Originally posted by SCDIV1:
endless posts asking about mostly meaningless BS

That doesn’t apply to 99.9% of bracket cars and bracket racers!

Again this isn’t the forum for you.

On my TD which is pretty much bracket racing I ran 200#@8000 RPM. Ron's billet twin gear 12.9 gal pump and Enderle K valve. Pressure taken right at the pump outlet.

It’s not! You were towed to the lanes and back to the pits and nothing about the engine in your former TD is comparable, equitable, nor the same as the junk on this shytbox.

Thanksd Bender. The 200 psi interesting. I am assuming you have pump saver on car. Have any idea of what pressure went to when shutting the throttle at top end? Asking because never had 200psi system on car. Although WOT pressure would not have anything to do with pressure at shutdown. I know my old TA/D stuff had a 175 psi I check. Most K valve spools only have fuel at that point when shut.

But, but, but, I did have to dial in......

I'd have to get my old laptop out to see what the pressure did when I lifted, can't remember off hand. I ran high pressure because I thought it might atomize the fuel better.

Well 4 things done today.

1 Got good info from bender

2 upset edna

3 proved edna can not resist commenting even when the subject is out of his wheelhouse and he has nothing to ad.

4 edna admitted his bracket car is a shyt box.
nothing about the engine in your former TD is comparable, equitable, nor the same as the junk on this shytbox. Your words.

oh yea, edna I learned a long time ago do not to listen to ediots. Injector size has nothing to do with pump pressure on MFI which you know not a damn thing about and why your post are just lil bytch bumbling some useless crap.

Ok got my extra bonus points for deal with retard for the month. bye now.

quote:

Originally posted by "The Bender":
But, but, but, I did have to dial in......

But, but, but you didn’t want to and couldn’t dial any quicker than 6.10 with the NHRA.

quote:

Originally posted by "The Bender":
I'd have to get my old laptop out to see what the pressure did when I lifted, can't remember off hand. I ran high pressure because I thought it might atomize the fuel better.

Agree with thinking on high pressure and atomization.

See edna atomization is when the ful is prayed in a finer form more like a mist than having big droplets. The bigger droplets are harder to ignite. Which means less efficiency. Hope I made that simple enough. You are welcome in advance.

quote:

Originally posted by 1320racer:

quote:

Originally posted by "The Bender":
But, but, but, I did have to dial in......

But, but, but you didn’t want to and couldn’t dial any quicker than 6.10 with the NHRA.

Like I always say, 6.10? That's cute.

Looks like bender just need more binders to slow his stallion down to meet the speed limit.

Interesting. You ask a question about MFI and you get a response from a MF'ing midget who knows nothing about the subject at hand.

I usually ran between 80 and 110, and found no real gains at the higher pressures.

quote:

Originally posted by Bucky:
Interesting. You ask a question about MFI and you get a response from a MF'ing midget who knows nothing about the subject at hand.

I usually ran between 80 and 110, and found no real gains at the higher pressures.

That funny as he11,well lot funnier than that.

Bucky, I am taking it you ran higher too? Since stated never found any gains with higher pressure. How about consistency? Better or same with lower pressure. The higher atomization should give more power in theory.We all know how that works at times.

A 100 psi not bad deal. Heck, More fuel system guys using 100 pis flow rating nowadays. My mentor Ralph Gorr used 150 and all of my numbers work off that so I stick in that area. Heck has worked good for me this long.

On my data logger I record fuel pressure at 7,000 RPM to have a consistent data point. I use same RPM as the reference and it will help you tell if something is wrong. I have ran from 50 PSI to 150 with no difference in ET.
Some will say at least 125 PSI is required to atomize the fuel. I do not buy into that theory now but you can run what ever you want.

Does not matter much as long as you get right amount of fuel in the motor. IMHO.

quote:

Originally posted by wideopen231:

quote:

Originally posted by Bucky:
Interesting. You ask a question about MFI and you get a response from a MF'ing midget who knows nothing about the subject at hand.

I usually ran between 80 and 110, and found no real gains at the higher pressures.

That funny as he11,well lot funnier than that.

Bucky, I am taking it you ran higher too? Since stated never found any gains with higher pressure. How about consistency? Better or same with lower pressure. The higher atomization should give more power in theory.We all know how that works at times.

A 100 psi not bad deal. Heck, More fuel system guys using 100 pis flow rating nowadays. My mentor Ralph Gorr used 150 and all of my numbers work off that so I stick in that area. Heck has worked good for me this long.

I played with a bit higher but didn't see anything favorable performance nor consistency. Before direct injection, it was rare to see oem's over 100 psi on efi. So they didn't see any big advantage in power or economy it seems.

Thanks, Bucky. You tree'd me on a question I had in mind about efi pressure

Enderle 80a-1 Flow 6.05GPM @ 100PSI 4000 pump rpm.
Approximately 115 psi at 7500rpm at the port nozzle distribution block.
.031 Enderle nozzle jets. Kinsler AS (screened) atomization nozzles with 3 - .125 nozzle vents.
.110 main pill - target AFR 5.0 – ~1100 -1150 EGT
K-valve secondary check 32psi idle check 3psi
BV linkage (clickfast) set for 400 - 450 degrees Idle EGT ~6.0 AFR
FIE launch lean-out: .030 pill set for 700 degrees EGT.
Kinsler High speed: .045 pill @ 95psi
Leaked @ % Blade gap @ .010 Idle RPM ~1600.
5.98 @ 114 – 3250lbs 440cuin

quote:

Originally posted by Curly1:
Does not matter much as long as you get right amount of fuel in the motor. IMHO.

Not that things can't be optimized, but this is pretty much it right here.

I've heard of people installing nozzles upside down, so they spray up toward the throttle body instead of down toward the head. Ran just fine.

When I went to Denver, I should have gone down 3-4 nozzle sizes but I didn't have any nozzle jets. Just used the pill to lean it out, about 20 numbers higher. Pressure would theoretically be a good bit lower. Ran just fine and won the event.