What Should I Set FPR to?

[TSITuner4Lyfe69]

ok im gonna run 18psi is this a safe setup? but Whats should i set my FPR at?
evo 3 510cc injector
16g
255lph walbro
universal ajustable fpr *********(what should i set at?)****************
ported evo 3 manifold
megan racing 3inch downpipe
o2 dump
3inch PVC intake with K&N filter

 

[absolute_DSM]

You set it at the stock psi. I believe for you its 37.5 with the vac line off.

An FPR is nice to adjust the fuel pressure, but its main purpose on a DSM is to hold the higher pressure of a high flow fuel pump without being over run.

 

[snowborder714]

1G auto - Spec 42.7psi (Standard value 41 - 46 psi)
1G manual - Spec 36.3psi (Standard value 36 - 38 psi)

Make sure you set it with the vacuum line disconnected.

 

[TSITuner4Lyfe69]

someone was telling me to set it at 43psi to run 18 psi?

 

[snowborder714]

Your base fuel pressure should always be set at it's spec, no matter what psi you're pushing. There are some people who are running non-stock fuel pressures, but they know what they're doing. There is probably less than 1% of people on here that are doing that.

Just follow what everyone's been telling you and you'll be fine.

 

[SBR Joe]

Set it at 45 psi with vac line off. Most injectors get theyre cc rating from being tested at 45-50 psi of base fuel pressure. So if its not running that your, for example, 680cc injectors may only be flowing 620 or so. Ya digg?


Joe

 

[TSITuner4Lyfe69]

alright well i have 550cc THANkS ALOT JOE I'll Set it at 45psi

 

[TSITuner4Lyfe69]

im guessin 45psi is good if your running aftermaket injecotrs because thats what they test them at

 

[GVR4592]

What are you using to tune with and why does your list not match the modifications in your profile?

 

[TSITuner4Lyfe69]

this is a new car i will update my profile tonight for sure but im not tuning with anything right now

 

[GVR4592]

What will you be using to compensate for the 510 injectors and the high fuel pressure?

 

[TSITuner4Lyfe69]

The Regulator? and they run fine in the car now with out a regulator just the stock one?

 

[firefightermdc]

what's safe be for the 2g's?

 

[turbosax2]

what's safe be for the 2g's?

43.5 psi with the vacuum line off and plugged.

 

[snowborder714]

what's safe be for the 2g's?

Are you talking about fuel pressure? If so, 2g fuel pressure is 43.5psi. If not, please clarify what you're talking about.

 

[GVR4592]

The Regulator? and they run fine in the car now with out a regulator just the stock one?

That won't work and I doubt it's running fine. Do you have a datalogger or a wideband?

 

[VETTE_50_TH]

You are only setting your base pressure for the amount of fuel. Think of the base pressure as a broad area, but you want to narrow it down along along the rpm range. Thats why dsmlink, safc will do. Allow you to tune the actual amount of fuel so you do run to lean or to rich at a certain amount of boost, for a certain fuel type, and knock. Correct me if im wrong mods. Thats what i have gotten out of tuning.

James

 

[kenamond]

TSITuner4Lyfe69: Re-read post #3. Do you have a A/T or M/T ECU?

Without any fuel controller, you're already dumping TOO MUCH fuel with LARGER than stock injectors. Increasing the base fuel pressure (to 45 or whatever) will cause you to inject EVEN MORE fuel. The fuel pressure used to rate an injector has as much to do with this thread as the price of rice in China. The ECU thinks you're running either 390 injectors at 42.7psi base fuel pressure (if it's an A/T ECU) or 450 injectors at 36.3psi base fuel pressure (if it's a M/T ECU). Your injectors are larger than either of those *and* you're agreeing to run 45psi base fuel pressure? Stop and think about it for a minute.

Get SAFC or *something*.

 

[TSITuner4Lyfe69]

i am M/T so what should i do right now with the 510cc inkectors should i turn down the fpr?

 

[kenamond]

i am M/T so what should i do right now with the 510cc inkectors should i turn down the fpr?

At a minimum, you should get a logger and a fuel controller or put the 450s back in and set your fuel pressure to the stock spec and run 15psi boost or lower. You shouldn't upgrade your injectors until you have a way to compensate for the extra fuel (SAFC, DSMlink, etc.) and know when you've got it right (logger, DSMlink). You basically skipped something in the upgrade path by going larger injectors first. I'm not going to recommend anything else. Sorry.

 

[VETTE_50_TH]

Read this carefully and slowly. SAFC TUNING

James

 

[tstkl]

Your base fuel pressure should always be set at it's spec, no matter what psi you're pushing. There are some people who are running non-stock fuel pressures, but they know what they're doing. There is probably less than 1% of people on here that are doing that.

Just follow what everyone's been telling you and you'll be fine.

funny how he doesn't listen to the right answer, he listens to the guy who owns a shop and tunes cars for a living. But then again, they SHOULD be the same answer. Unfortunately they aren't in this case. snowborder714 knows what hes saying, you don't know what your doing, so don't touch it. Leave it at the stock specs until you know EXACTLY what adjusting it does. Not just the equation of how it rises, but also what having a high base fuel pressure on a high boost car will do and such.

basically, quit looking for the answers you want to hear and look at the correct answers


and get a datalogger. get one. PERIOD. Although the aem ems you have listed for sale would work. So would the dsmlink you have listed for sale too. Hmm,... why did you "buy" both and why are you "selling" both now? Do you even have either of them, or could that be a scam?

 

[90talontsi90]

alright then man thats cool apreciated im gonna get a safc but htat useless to me as i really and useless when tuning

Well take it slow and steady and if you need help there are thousands of dyno shops and almost any preformence dyno shop will know how to work a SAFC if you having problems. But first things first.
Step #1 take out injectors
Step #2 put in stockers
Step #3 change oil**

**If you've been driving around with those 510s dumping in fuel like crazy then I can tell you from personal experience that a lot of that fuel has gone past your rings and into your crankcase. Gas is not an oil that I'd recomenced for anyone to use in their cars, and that gas/oil mixture is not going to be doing good things to any of your bearings.

 

[TSITuner4Lyfe69]

ok but why cant i run the 510cc injetors when my motor came stock with them(cyclone)?? do i have to use the jdm ecu also?

 

[steve]

ok but why cant i run the 510cc injetors when my motor came stock with them(cyclone)?? do i have to use the jdm ecu also?

Ah your starting to grasp it.
Yes, the ECU knows about the injector flow rate. So the matching JDM ECU is programmed for the 510cc injectors just like the 1G factory DSM manual ECU is programed for 450cc injectors being used at 36.3 psi and the 1G automatic ECU for 390cc injectors at 42.7

There are a slew of other things the ECU knows about including the octane of the fuel used (indirectly by the timing maps) as wells as hardware differences that would make running the JDM ECU a poor choice to solve your problem.

Get an SAFC or a chip programed for your injectors.