ERAUMAZDA

I am shooting for 290 ~ 300 to the wheel. I plan on using either 680cc injectors and 850cc secondaries a walbros pump, and fmic. Will this be safe to run on the SAFC if tuned right.

deltr0n`

i'd save your money, dont buy the safc, dont buy the injectors, get a better pump (denso comp pump) and get a RRFPR from bell...thatll put you pretty damn close to your desired numbers, then save some more money and get a standalone. piggyback is a waste of money if you plan on getting anywhere later on down the line.

ERAUMAZDA

I did figure that was the best route. I want to go stand alone but its so close to my budget

deltr0n`

yeah i'd just wait...hell that IS what im doing, as soon as i get my check im getting that bell regulator, and maybe a few other goodies, but with the regulator and a good pump, you can support 15 lbs. no problem, and thats what i creep to, so its perfect to play around with untill i got some serious cash saved up to get standalone and porting done.

F1blueRx7

iTrader: (5)

Isn't this going to make it run really rich? You'd need some sort of fuel computer to pull together the added fuel going into the engine, right?

ERAUMAZDA

I thought I need a linear fuel regulator 1:1.

deltr0n`

no you need to tune the RRFPR, its not just a bolt on.

ERAUMAZDA

but fuel pressure is suppose to rise 1 psi for every pound of boost.

deltr0n`

Pressure calculation: the fuel pressure required increases with the square of the boost pressure ratio:
Example: 6 psi boost is a pressure ratio of 1.41. With stock fuel pressure of 36 at zero boost, than:

Needed fuel pressure = ( PR2 x 36) + boost = (1.412 x 36) + 6 = 77.5 psi



http://www.bellengineering.net/Pages...struction.html

ERAUMAZDA

you didn't read that page right.

OEM System Regulator: diagram 2022 is linear

Aftermarket Turbo/Supercharger Regulator : 2025 non linear

pip

In theory if you had the rtek7 chip you wouldnt need the safc, I say in theory because i havent seen any post about the v1.5 yet but im pretty sure those guys wouldnt release a bum product

NZConvertible

Rising rate FPR's are a crude band-aid for injectors that are too small. Stick with a linear rate FPR and get the right injectors for your goal. A set of four 720cc/min injectors will be adequate for 300rwhp, with a bit of headroom for further mods.

Bukwild

Stand alone first. Stand alone and tuning can get you the numbers you want safely. I always hear people on this forum talking about saving up money to get a stand alone after getting a upgraded turbo and some used fuel injectors of ebay. This is a bad idea if you ask me.
2 things kill our cars. Clogged/old fuel injectors and overheating. Never use used fuel injectors and if you do send them to RC to be cleaned and flow tested. Spending a couple of extra bucks in the right areas save you thousands in engines and down time.

ERAUMAZDA

won't 4 720cc make my idle high and rich.

ERAUMAZDA

When u run the FPR do u run it on the same line as the stock regulator? Do have have to remove the stock regulator?

jacobcartmill

iTrader: (6)

dont get a rising rate FPR. get some injectors and an safc and you'll be fine.

of course its always better to get a standalone, but you'll be fine with injectors and a safc

imloggedin

whats wrong with an RRFPR? just for my knowledge.. i dont know much about them.

deltr0n`

theres absolutely nothing wrong with it, and its hardly a CRUDE bandaid.

- its safe
- you dont need to waste your money on a piggyback/injectors (you will need bigger injectors later on anyways if you plan on pushing any decent numbers)
- once you get a standalone you can still use it.

i dont understand why some people will waste their money on an safc, injectors, and tuning when they are just going to have to do it ALL over again when they get a standalone.

with the $259 model you run it along with your stock FPR, to get a base, but with their new model im pretty sure it replaces your stocker.

NZConvertible

Cranking up the fuel pressure far beyond the pressure things were designed to work best at, just to force more fuel through, is crude. It's the easy way around undersized injectors, and the easy way is seldom the best way. That's a dangerous assumption. It does not make you set-up safe, there are many other considerations. A RRFPR doesn't need a fuel controller? How does something that completely changes the fuel curve not not a fuel controller? How is that not crude? Simply jacking up the fuel pressure under boost is going to result in mixtures richer than they need to be. You have no control of the amount of fuel injected through the rev range. To accurately compensate for the fuel pressure change you need a fuel controller. If you have one of those then you should just spend your money on bigger injectors instead of a new FPR.

You also have to seriously consider pump capacity. A FPR doesn't create pressure, it simply restricts fuel flow. The pump still has to be able to make the higher pressure at the required flow. At higher pressure the pump cannot flow as much. Perhaps it's because they want their engine to run safely and efficiently. Perhaps it's because they have no plans to get a standalone.

deltr0n`

who said anything about "Cranking up the fuel pressure far beyond the pressure things were designed to work best at" not me...

you like jacking/cranking things up dont you? there you go again, once again i didnt say anything about JACKING up the boost...

and NO you dont need a piggyback for a RRFPR, you dont just bolt the **** on, you TUNE it... thats why you need a pump to support the higher fuel pressure, walbro's get maxed out i know that for a fact, a denso pump on the other hand is plenty.

but hey if you wanna spend a ridiculous amount of money on un-neccesary things then go for it, no one is stoping you.

im not going to say anything else about it because there will always be someone like you, saying just because you dont like it, means you shouldnt do it...

NZConvertible

That's what a rising-rate FPR does! It increases fuel pressure far more than a linear-rate one does. Instead of keeping fuel pressure at fixed amount above manifold pressure, the pressure differential increases as boost increases. It's the higher fuel pressure that forces more fuel though the injectors. What did you think it was doing?

Neither did I. I'm talking about fuel pressure...

You cannot "tune" an engine with a regulator, that's just silly. All you can do is set the static pressure. A RRFPR totally changes the fuel delivery curve and hence mixtures. You may get the mixtures you want at some points but it'll be richer than it should be at others. That's why you should have a fuel controller.

You may be happy with overly rich mixtures, bit I certainly wouldn't be.

deltr0n`

ah well, i dont feel like arguing about it...we both gave him 2 different ways to do it, let him decide which one is best. if you dont want big numbers, yeah sure go with a piggyback, get yourself some injectors and keep it at that. however if you want big numbers with a standalone the way i suggested is going to save you a bunch of money and time.

its really up to you how you want to set up your car.

oh and i sure as hell hope wherever you take your car to get tuned will have something to tune it with, not just through the FPR. unless you do it yourself.

gsracer

If you go with a stand alone, you won't want a RRFPR, that'll just make tuning it harder.

If you're sticking with the stock ecu and going with a hybrid, for fuel I'd recommend.

4 x 720cc injectors
walbro/fd fuel pump
SAFC (wired via pressure sensor for almost sane gas economy)

NZ already hit this many posts ago.

Honestly I think RRFPR's are ok, even if crude. However, you'll still want a safc or something similar to fine tune it.

ERAUMAZDA

but why not 680cc and 850cc setup

gsracer

It's a lot easier to tune the safc if you're using equal sized primary and secondary injectors.