Stock fuel pressure is 3 bar or 42psi. Upgraded fuel pressure is normally 4 bar or 56psi. We do this to effectively make our injectors "bigger." Well, how "big" can I make my injectors via higher fuel pressure? Can I run 5 bar? 6 bar? 20 bar? As long as I have the SAFC, E-Manage, or whatever I could adjust for the added fuel. What determines the limit of how high one can turn up the fuel pressure on our cars? Fuel pump? Hoses? Limit of the FPR you use?

4 bar or 58.8

370cc @ 3bar 43psi = 370cc or 35.2 lb/hr = 253hp @ 90% DC

400cc @ 3bar 43psi = 400cc or 38.0 lb/hr = 274hp @ 90% DC

400cc @ 4bar 58.8psi = 546cc or 52 lb/hr = 374hp @ 90% DC

370cc @ 4bar 58.8psi = 505cc or 48 lb/hr = 346hp @ 90% DC

It appears SR20DET 370cc injectors actually flow more closer to 400cc than 370cc. Its also been said that the 300ZX injectors are different than SR20DET 370cc injectors and only flow 370cc. RC engineering has reported this.

http://www.se-r-list.org/archives/1999/1999-05/msg02316.html

My bad: 1 bar = 14.7psi not just 14psi :cool:

Your bad: 1 bar = 14.5 psi.

Actually I thought it was 14.7 but this proves it: 1 bar = 14.50377 psi. You can go to http://www.chemie.fu-berlin.de/chemistry/general/units_en.html and do all sorts of cool conversions right there online.

Brent

I just got a set of the 370cc injectors and want to know what they are these supposed to look like?
What part numbers should appear on them? I bought these used from someone off the se-r.net, but how do I know that these really are the 370cc ?
Thanks

nx2k-boosted : please try to stay on topic. Your question has nothing to do with the title of my thread.

Back to the real topic, why can't I run 20 bar of fuel pressure?

Some fuel system components probably aren't rated for more than 10 bar?

Originally posted by Ben92SentraSE-R
Back to the real topic, why can't I run 20 bar of fuel pressure?
I wish I knew, its an interesting question. At some point I think the injectors might not be able to close against the pressure of the fuel. But I've never seen a schematic or taken a fuel injector apart to know how they open/close.

Enough about what 1 bar really is. Make your own thread if you want to argue! :) Concentrate on my question! :D

Well, if you ran 5 bar of pressure, you would effectively make your injectors even bigger. Why not do so?

OKay finally after doing some research, I still believe that 1 bar = 14.7

1 atmosphere = 760 mmHg = 29.92 inHg = 14.7 lb/in Squared = 101.3 kPa

Okay now that I got that off my chest. Back to the topic.

Yeah but what makes you think you can flow the desired rate at that specific bar, as far as your Fuel pump is concerned?

1 bar does NOT equal one atmosphere. That's where you're erring. 1 bar = 100 kPa.

Ben, I don't think you'll find anyone on the boards who can tell you the maximum pressure that the injectors can work with. You'll probably bump into a limit where the idle duty can't be made short enough.

http://hyperphysics.phy-astr.gsu.edu/hbase/pman.html

http://www-star.stanford.edu/projects/mod-old/id-pres.html

Read and head. Bar. Barametric pressure

Originally posted by Slartibartfast
1 bar does NOT equal one atmosphere. That's where you're erring. 1 bar = 100 kPa.

Ben, I don't think you'll find anyone on the boards who can tell you the maximum pressure that the injectors can work with. You'll probably bump into a limit where the idle duty can't be made short enough.

Neither of your references equates 1 bar as 1 atmosphere. My handy-dandy Engineering Handbook of Conversion Factors lists 1 bar = 14.5 psig.

Process Associates of America (http://www.processassociates.com/process/convert/cf_prs.htm)

Who is TPS Quinn? (http://users.aol.com/tspquinn/units.html)

New Jerusalem Church(!) (http://www.njcnews.org/compute/pumps.htm)

Coweeta Long Term Ecological Research (http://sparc.ecology.uga.edu/webdocs/tools/html/convert.html)

Each of these will show you the error of your way. There are many more sites that will do these same conversions. I just input "engineering conversion factors" into Google to find these.

also, the higher you go on fuel pressure, the more you tax all the lines, seals, etc that are in your fuel system. there is a lot of line that could rupture if you go too far past its original design parameters.

also, you injectors may not be able to stay closed when you set the fuel pressure too high. i would stick with 4 bar, or maybe 5 bar if youre feeling saucy.

I could show you just as many sites that show the exact opposite, so what's your point? Have you ever gone diving? First thing you learn is Atmospheric pressure is = to 14.7

http://search.yahoo.com/bin/search?p=1+bar+atmospheric+pressure

Here is a Yahoo search on yep you guessed it 1 bar atmospheric pressure.

Originally posted by Slartibartfast
Neither of your references equates 1 bar as 1 atmosphere. My handy-dandy Engineering Handbook of Conversion Factors lists 1 bar = 14.5 psig.

Process Associates of America (http://www.processassociates.com/process/convert/cf_prs.htm)

Who is TPS Quinn? (http://users.aol.com/tspquinn/units.html)

New Jerusalem Church(!) (http://www.njcnews.org/compute/pumps.htm)

Coweeta Long Term Ecological Research (http://sparc.ecology.uga.edu/webdocs/tools/html/convert.html)

Each of these will show you the error of your way. There are many more sites that will do these same conversions. I just input "engineering conversion factors" into Google to find these.

You're both correct.

1 bar = 10^5 N/m^2 = 14.50 lb/in^2

1 atm = 14.7 lb/in^2 = 1.013 X 10^5 N/m^2

Source: Physics for Scientists and Engineers 5th Edition