OK, I'm in the process of installing my aftermarket fuel pressure regulator.
Installation seems pretty straight forward.
However, when I come to set it what PSI can I go to?
The manual states between 38-44 PSI as standard.
Can I increase the PSI over 44, if so to what PSI?

Also, what PSI can the standard Fuel Pump cope with?

Any help would be greatly appreciated.

BTW: I have a '97 ST with standard injectors, an Injen IS2040 intake, Denso Idridium spark plugs and Magnecor KV85 spark plug wires.

I think the standard psi is 35+.

You can set to a high value, but try not to go over 50psi on stock injectors.

If you have a SAFC, then 44+ is possible, if not, you will fun to rich.

West_minist thanks for the info.

I think I'll start at 40 PSI considering I have an intake on (increased air flow).
Then, after I have everything I want installed, I'll get the car dynoed and play around with the pressure to see what the best setup is.

I'm getting a SAFC II for my st-185 swap. What should i do about the AFPR? What brand? At what psi? Where can i get one pretty quickly?
>> >> >>

-ToYCeLi8+Aug 17, 2003 - 11:09 AM

-97sccelica+Aug 17, 2003 - 12:12 PM

-vphmc+Aug 16, 2003 - 9:25 PM

-ToYCeLi8+Aug 17, 2003 - 7:24 PM

-vphmc+Aug 17, 2003 - 12:34 PM

In order to play it safe, I'm going to initially set the fuel pressure to the standard settings as indicated in the Haynes manual I have, that is, in the range of 38-44PSI.

Gauges are on the list of items to buy soon...
AutoMeter A/F Ratio, Fuel Pressure and Temperature.
I'm also in on the Lotek Pillar 3 Gauge group buy.
However, I want to get a header and high flow cat first.

Later on I'm looking at uprating the fuel pump and injectors.

For those that are curious, I'm looking doing a 7afCe
(A compressor setup).
That will give me better acceleration than a Turbo set up (no lag).
...and if that's not enough there's always Nitrous! >>

-west_minist+Aug 17, 2003 - 2:33 PM

Thanks for the advice.

I installed my Cosmos Racing AFPR today.
I set the pressure to 40PSI.

I then revved the engine "fiercely" to see what the gauge reading was doing.
Interestingly enough it rises to about 45PSI when I increase the throttle abruptly and when I let the throttle off abruptly it drops to about 35PSI.
It idles at 40PSI.

This seems good to me and safe as it is within the manufacturers setting range of 38-44PSI.

BTW: Having fitted the Injen IS2040 intake, Denso Iridium plugs, Magnecor KV85 spark plug wires and AFPR, I took it for a spin and noticed a substantial difference in acceleration.

When I have my other parts fitted (exhaust, header, high flow cat, underdrive pulley) I'll being getting it dynoed correctly.

-SpedToe169+Aug 17, 2003 - 10:46 PM

-west_minist+Aug 18, 2003 - 6:28 PM

Toyceli8, don't bother with the SAFC2. How about skip the wiring crap and the SAFC2 and get a standalone engine management system. such as the PRS8 over at PerfectPower.

One very very basic thing that has been overlooked is...spark plug colors.
They give a very good indication as to whether you are running to rich or too lean. >>

Also, something to bear in mind is that the standard ECU uses the standard sensors to track and adjust the A/F ratio electronically. So I'm assuming that even with an S-AFC connected (but not set) its the ECU that is managing everything.

To gain optimum performance the S-AFC has to be set correctly and IMHB the best way is to get dynoed.

I believe unlike you, he is not going to be racing or always looking for that little bits for each part added to win that race.

Why put him through the added rising expense when more can be done before a full tune.

You think just by adding a AFR should demand one large tuning experience? >>

We all know that different cars have different emission standard to some points. Some cars like to run lean because there are program to produce less emissions. So increase fuel is not always warrant. Just like the wrx aftermarket changes. Soo much is tied in tuning by the cpu, you have to know what you are doing.

Who the hell would like goingthe street running rich. I believe he and other knows what it looks like to be running rich.

The o2 sensor going bad would not trigger the ecu to display a faulty o2 sensor until it is really gone. Why you think that the bigger case like Mercedes and BMW are coming up early stats for sensors.

I personally believe that there is a difference in need for race tuning and street tuning when advising someone.

I just you should take him under your arm when he has done all of these dynos and let him have your successful career.

Nice talking to you

>>

-snadman+Aug 18, 2003 - 10:36 PM

It replaces your ECU and offer you flexibility in tuning and engine management in a nutshell.

if anyone needs a FPR let me know. i have one with a gauge
adam

-ToYCeLi8+Aug 19, 2003 - 12:16 PM

While we're on the topic of fuel pressure regulators....Would an FPR deliver more fuel by the increased pressure, and would a FPR, an ignition unit, and proper guages be a good route to go for N/A tuning?? Or would i get better results if i got an S-AFC, and possibly an ignition unit so i could run rich on that, then compensate with the ignition upgrades?

-Silver94CelicaOwner+Aug 20, 2003 - 1:45 PM

Stand alone systems just cost so much... If I were doing an engine swap I might get one, but not for flexability. Get a Super AFC.

Jon

So what exactly will a fuel pressure regulator do for your engine??

Sorry for the n00b sounding question, i just want to understand this better. >>

The AFPR (Adjustable Fuel Pressure Regulator), as the name suggests,allows you to adjust/regulate the pressure or the amount of fuel to the fuel rail thus the injectors.

The AFPR alone probably wont do much other than make your car run rich if you set the pressure to high.
It's an upgrade that I did with a combination of other things.

I read somewhere that to increase basic performance you need to upgrade the fuel distribution, air intake and ignition.

So, I have the AFPR installed with an Injen Intake, Magnecor KV85 leads and Denso Irdium plugs.
To make them work all together properly you need to adjust the Air/Fuel ratio hence why I got an S-AFC (Super-Air/Fuel Controller).
You'll also need to upgrade your exhaust system (Header, High Flow Cat and Cat-back system) to get rid of the extra gases better.
I have a Greddy SP cat-back exhaust (not fitted yet).

It's really a question of what do you want to do and where do you want to go?
If you're looking to Supercharge or Turbo later on these upgrades will help.

I didn't want to go the full SC/Turbo straight away because of the down time (and finances).
So I've decided to do things in stages.
I wanted items that I could "bolt on" myself and still use the car.

The next upgrade I would like to do is get a header and high flow cat, then an ignition module and coil (Crane Cams HI-6S).
Thereafter, I'm looking at upgrading the Fuel Pump and Injectors.
Then, when I have the finances, I'll go either the SC or Turbo route.

There are others on the board that are more qualified than I to answer your questions but I hope this helps a bit.

Thanks vphmc, thats the kind of response i was hoping for. I think i have a good understanding of how the AFPR comes into play now....i was just wondering what a good tuned N/A engine setup would be, and as far as i know the way to go about doing that is to increase fuel delivery(AFPR) and the power of the ignition(ignition box, coil)....so now could i just install a AFPR and ignition system and have it tuned properly by a shop and be done, or do i need to use a S-AFC to help integrate the higher volume fuel delivery with the air??

This is where I would start ...
First of all, you can get what I call "bolt-on" no tuning parts,
that is, parts you can bolt on without having to tune them.

I'd start with an Air Intake either RAM or Cold Air.
Next I'd get decent set of irdium plugs (Denso, NGK, ...).
Next a set of leads (Magnecor, Nology, ...).
Then you get an AFPR. Adjust/set it to the factory PSI settings (38-44PSI) to start with. Adjust the PSI up or down depending upon the color of your plugs - they should be a light brown/tan color if the engines running correctly.
I would then go for an exhaust.
Just with these items you'll notice the difference in acceleration.

Later on you can get an ignition module (+ trigger adapter) and coil - there expensive c$250-300.

Thereafter, you start getting into the Tuning parts.
The S-AFC falls into this category. (Having said that you can fit one without tuning it, which is what I have done).
The S-AFC connects/wires up to the ECU and is used to convert/override the settings sent by the sensors of the engine in order to optimize the Air Fuel ratio dependent upon what you have fitted (intake, AFPR, ...).
This will need to be done by a shop with a dyno facility.

Bear in mind that once you have it dynoed the majority of items you add afterwards will mean that you will have to have the S-AFC re-dynoed.

I suggest getting all your parts, fitting them all and then get the S-AFC dynoed.
(That's what I'm doing).

Bit of a long reply but I hope it helps.