Stock Fuel Pressure at the rails.
11-14-2007, 09:06 AM
#1
Stock Fuel Pressure at the rails. I searched under FP and Fuel Pressure and didnt find what I need....
I am running the RC calculator on top of the page, i.e. the Sticky.
I am at some point looking at 500 crank hp (est) with a
346 LS1
Intake (SLP flow pac)
Ported 90/90
Stock heads
LT dynatech headers
HIGH flow cats (from dynatech)
Corsa Cat back
Mild cam 228/230 @ 112, stock rocker ratio.
On a m6 driveline with a Moser 12 bolt.
I am est with tune and driveline subtraction its about 500 crank possibly and 420ish rwhp. If I am off, pls correct. I am just interested in crunching # for the future project(at least a year).
On the calculator, its already filled in for 43.5 at the rails
http://www.rceng.com/technical.aspx
With that varible im looking at 39.29 # injectors, i.e. 42 pound green tops.
Does this seem accurate or are the assumptions on HP and FP at the rails off.
Thanks in advance.
I am running the RC calculator on top of the page, i.e. the Sticky.
I am at some point looking at 500 crank hp (est) with a
346 LS1
Intake (SLP flow pac)
Ported 90/90
Stock heads
LT dynatech headers
HIGH flow cats (from dynatech)
Corsa Cat back
Mild cam 228/230 @ 112, stock rocker ratio.
On a m6 driveline with a Moser 12 bolt.
I am est with tune and driveline subtraction its about 500 crank possibly and 420ish rwhp. If I am off, pls correct. I am just interested in crunching # for the future project(at least a year).
On the calculator, its already filled in for 43.5 at the rails
http://www.rceng.com/technical.aspx
With that varible im looking at 39.29 # injectors, i.e. 42 pound green tops.
Does this seem accurate or are the assumptions on HP and FP at the rails off.
Thanks in advance.
11-14-2007, 11:00 AM
#6
WOT is going to cause the highest fuel consumption, and is where I see my lowest fuel pressure readings (as logged when I tune my car with HPT, and seen on the FP gauge), so that will be your worst case scenario. You always design to the worst case conditions.
BUT...you need to see what YOUR fuel pressure is doing at WOT. There aren't many people that run a FP gauge, or at least an electric one where you can watch it while you drive instead of a mechanical one that is mounted on the fuel rails.
An easy, and relatively cheap way to watch this would be to get a mechanical gauge mounted on your fuel rails (if you don't have one already), and put your car on the dyno and have someone watch it while you do a WOT pull. An electric fuel pressure gauge/sending unit is not a cheap proposition, but the data has been invaluable to me, and has explained my abnormally high injector duty cycles at WOT (I run 30-lb/hr Bosch injectors on my stock internal car to compensate).
BUT...you need to see what YOUR fuel pressure is doing at WOT. There aren't many people that run a FP gauge, or at least an electric one where you can watch it while you drive instead of a mechanical one that is mounted on the fuel rails.
An easy, and relatively cheap way to watch this would be to get a mechanical gauge mounted on your fuel rails (if you don't have one already), and put your car on the dyno and have someone watch it while you do a WOT pull. An electric fuel pressure gauge/sending unit is not a cheap proposition, but the data has been invaluable to me, and has explained my abnormally high injector duty cycles at WOT (I run 30-lb/hr Bosch injectors on my stock internal car to compensate).
11-14-2007, 11:07 AM
#7
I have a dyno that can do FP, its cheap for me but im going to build the car and bring it down for a one shot deal, from what I have seen #34 Racetronix will do quite fine.
Thanks for the help.
Anyone one else, feel free to chime in
Thanks for the help.
Anyone one else, feel free to chime in