how do you guys feel about rising rate fprs.... compared to a fmu?
02-16-2006, 02:42 AM
#1
0.5 BAR
Thread Starter
Join Date: Nov 2005
Location: new phila
Posts: 169
how do you guys feel about rising rate fprs.... compared to a fmu?
...yea basically that...
and what ratios to these come in... 1:1 and 2:1? ....
im only looking to run 5-7 psi and i think my 12:1 vortech fmu might be a bit much...
NO! ITS NOT A HONDA! so dont tell me to chip my ecu again...
and what ratios to these come in... 1:1 and 2:1? ....
im only looking to run 5-7 psi and i think my 12:1 vortech fmu might be a bit much...
NO! ITS NOT A HONDA! so dont tell me to chip my ecu again...
02-16-2006, 10:46 AM
#2
0.0 BAR
Join Date: May 2005
Posts: 0
Re: how do you guys feel about rising rate fprs.... compared to a fmu?
The so called fmu is a rising rate fpr. Vortech sells many different ratios I think from 4:1 to 12:1. If a 12:1 is too much try their 10:1, just make sure you gotta wideband on there to check and see if that one gets you the right air/fuel ratios. Also retard your timing a few degrees to be safe.
1:1 fpr won't do anything for you. That ratio is used only in conjunction with the ability to tune your ecu. 1:1 keeps the fuel pressure diferential across the injectors the same no matter how much boost you run.
So if you had 45 psi of static fuel pressure, and you boosted 30 psi, then your effective fuel pressure would be 15 psi. This is way too low and you injectors would max very quickly. You would then use the 1:1 FPR to keep the pressure differential at 45 psi.
1:1 fpr won't do anything for you. That ratio is used only in conjunction with the ability to tune your ecu. 1:1 keeps the fuel pressure diferential across the injectors the same no matter how much boost you run.
So if you had 45 psi of static fuel pressure, and you boosted 30 psi, then your effective fuel pressure would be 15 psi. This is way too low and you injectors would max very quickly. You would then use the 1:1 FPR to keep the pressure differential at 45 psi.
02-17-2006, 03:55 AM
#4
0.5 BAR
Thread Starter
Join Date: Nov 2005
Location: new phila
Posts: 169
Re: how do you guys feel about rising rate fprs.... compared to a fmu?
the thing is about a 12:1 is that i really dont want my injectors to see that much psi... i mean, my injectors will be nice and black after i put over 90 psi through them due to boost... what is somthing i could do to prevent that... im looking into megasquirt stand alone... but i dont have a laptop to tune with and i know nothing about tuning my car... i think stand alone is alittle much for an amateur such as myself...
02-17-2006, 06:43 PM
#7
1.0 BAR
Join Date: Dec 2002
Posts: 362
Re: how do you guys feel about rising rate fprs.... compared to a fmu?
I ran a 12-1 on my old motor and it was rich in boost. You could see some black smoke coming out of the exhaust. I changed to a 10-1 and it was a little better. You can get adjustable FMUs. That might be the best way to go for you. I think the Vortech adjustable is called the Super FMU.
02-17-2006, 09:03 PM
#8
1.5 BAR
Join Date: Nov 2005
Posts: 667
Re: how do you guys feel about rising rate fprs.... compared to a fmu?
if you dont want high fuel pressure then a fms is not really for you but if you dont have any choice then try using a little larger injectors with a lowered base fuel pressure and an ajustable fmu.
