FSE, Power Boost Regulators - garbage or useful?

[Lewis]

Hello!

I keep seeing these FSE Power Boost Regulators drifting around on eBay...

http://cgi.ebay.co.uk/Fuel-Pressure-Lan ... 0054706672



Like this.

Are there actually ANY benifits at all or is it just smoke and mirrors? I keep looking at them and just thinking "erm...."

[racer]

>Are there actually ANY benefits at all or is it just smoke
> and mirrors? I keep looking at them and just thinking
> "erm...."

They provide real benefits..which vary depending on the fueling system you have.

Fuel pressure regulators provide the baseline for ECU. With the fuel pressure as a given, the only thing the ECU need do to execute its programming is vary the injector duration.

Additionally, we all use RISING RATE fuel pressure regulators. This means that in demand situations, the regulator increases the fuel pressure (with a vacuum operated diaphram). The FSE has a steeper curve for this temporary pressure increase than stock. Ergo, it provides more fuel on steep demand than stock and the car reacts accordingly.

Additionally, all pressure regulators can fail slowly over time. An adjustable regulator with a permanently installed gauge, allows you to trim this out in a second.

Specifics...

FOR FLAPPER SYSTEMS

Flappers use simple analogue ECUs. They are truly genius like in their construction and thinking, designed by fellows who grew up with carbs. The "fuel map" is linear and there is no self-monitoring and few inputs. In a nutshell, increase the fuel pressure and you have changed the programming. Between the AFM spring tension, the idle air valve and the FSE, you can do as much or more than a box full of jets and needles and 4 carbs. OR a buffet of aftermarket chips.

For a flapper, a FSE is a super addition.

FOR HOTWIRES et al

These systems use digital ECUs with many more inputs. They are designed (increasingly) to be emission sensitive..(aka paranoid). You cannot use a FSE to increase fuel pressure and expect them to let you get away with it. The ECU will tumble into default mode.

The AFM is also not adjustable. One reprograms the digital ECU with an new eprom fuel map, not with a fuel pressure regulator and the AFM.

However, the benefit of being able to adjust your pressure to the proper level assures you that the ECU's baseline is precisely the right one. That is often a big help. Additionally, you still will benefit from the steeper curve in demand situations.

The permanent fuel pressure gauge is great. Engine problems normally divide into two large groups...spark issues or no fuel issues. It is nice taking a quick glance at a fuel pressure gauge to confirm that 50% of the possibilites are or are not involved.

racer

[Coops]

FOR HOTWIRES et al

These systems use digital ECUs with many more inputs. They are designed (increasingly) to be emission sensitive..(aka paranoid). You cannot use a FSE to increase fuel pressure and expect them to let you get away with it. The ECU will tumble into default mode.
racer

im sorry i don't agree,
i used a hotwire system until start of this year with a FSE rising rate fuel reg and had no probs with it going into default mode at all,
i ran the car fault free like this for 3yrs,

[Lewis]

That made for very interesting reading - fantastic stuff!

I have a flapper ( ) so I shall seriously considering investing in one of these - as you say, a permenant pressure gauge is a useful addition to any vehicle anyway. It'll allow me to see wether my EFi pump in the tank is actually making good, anyway.

RE the discrepancies using it on a Hotwire system - I don't think Racer is saying it wouldn't work, just that if the baseline map on the engine is wrong, it may knock the ECU out?

Hobgoblin prevents me from thinking around this subject any more

Oh, thev8kid - Your Capri is lovely bit of kit - spent a while reading up on your website, good stuff! From the numbers it looks like it really goes some

[GreenV8S]

The hotwire map should be correct for the engine.

If it is, then the air fuel ratio will be correct using the standard pressure regulator. If you then fit one of these FSE regulators which raise the fuel pressure under load, the engine will end up running rich. The result of that will be less power, worse economy, possible more wear, more coke and soot in the engine.

If you have an engine that is running lean under power then this is one way to address that - although not a very good way imo.

[racer]

FOR HOTWIRES et al

These systems use digital ECUs with many more inputs. They are designed (increasingly) to be emission sensitive..(aka paranoid). You cannot use a FSE to increase fuel pressure and expect them to let you get away with it. The ECU will tumble into default mode.
racer

im sorry i don't agree,
i used a hotwire system until start of this year with a FSE rising rate fuel reg and had no probs with it going into default mode at all,
i ran the car fault free like this for 3yrs,

\

You didn't follow what I wrote kid. I did not suggest that FSE wouldn't work with a Hotwire. They will and provide some benefits..(precise setting of the stock fuel pressure level and a steeper rising rate in demand situations).

However, they can NOT provide a Hotwire with a de facto programming feature as they do with Flappers. You cannot play with Hotwire fuel pressure and expect it to love you for it. It will interpret the extra fuel as a serious problem.

However, a Flapper has no feature that allows it to see and blow the whistle on the amount of fueling. It is linear anyway. Increase the pressure and you increase the fueling..allowing you to adjust for different enhancements, more air and/or greater capacity. It's not precise but it is VERY flexible...more like a carb than an EFI but with all the combustible spray advantages that any EFI offers.

racer

[racer]

That made for very interesting reading - fantastic stuff!

I have a flapper ( ) so I shall seriously considering investing in one of these - as you say, a permenant pressure gauge is a useful addition to any vehicle anyway. It'll allow me to see wether my EFi pump in the tank is actually making good, anyway.

Actually..the original idea to add these gauges (that everyone is selling with the FSEs) is my own. (says he with puffed up pride!) They only cost 10 pounds.. The FSE comes with optional entries fore and aft and a plugs for the unused side. I simply removed the plug and screwed in the gauge. It caught on with the racers....and when that happens the rest is always history.

RE the discrepancies using it on a Hotwire system - I don't think Racer is saying it wouldn't work, just that if the baseline map on the engine is wrong, it may knock the ECU out?

Thank you! You catch on quick.

racer

[racer]

The hotwire map should be correct for the engine.

If it is, then the air fuel ratio will be correct using the standard pressure regulator. If you then fit one of these FSE regulators which raise the fuel pressure under load, the engine will end up running rich. The result of that will be less power, worse economy, possible more wear, more coke and soot in the engine.

If you have an engine that is running lean under power then this is one way to address that - although not a very good way imo.

It could be far worse than that. You cannot fool around with the fuel pressure on a hotwire..or any later fueling system.

However, your comments on the rising fuel, pressure on demand evidence some confusion. You already have a rising rate fuel regulator on your hotwire and it is working fine. You can confirm this by glancing the vaccum hose at the rear of the regulator. If the pressure is made to stay constant as you say, why is the regulator designed to respond to engine vaccum?

The FSE simply responds faster. In a performance scenario, that tranlates into faster throttle response.

racer

[softdash3.9]

I use an FSE valve on my Rover SD1 Vitesse TP (without a gauge) works well

[GreenV8S]

However, your comments on the rising fuel, pressure on demand evidence some confusion. You already have a rising rate fuel regulator on your hotwire and it is working fine.

I understand that; I'm trying to differentiate between the standard rate regulator which drops the pressure by 1 psi per 1 psi of manifold depression, and the higher rate FSE valve which drops it by 1.7 psi per 1 psi of manifold depression.

They are both variable pressure regulators, they each have a constant rate (NOT rising rate), the rates are different.

[racer]

I use an FSE valve on my Rover SD1 Vitesse TP (without a gauge) works well

If you want to add the gauge, it is a doodle. They are sourced from the US online.

http://store.summitracing.com/partdetai ... toview=sku

racer

[racer]

However, your comments on the rising fuel, pressure on demand evidence some confusion. You already have a rising rate fuel regulator on your hotwire and it is working fine.

I understand that; I'm trying to differentiate between the standard rate regulator which drops the pressure by 1 psi per 1 psi of manifold depression, and the higher rate FSE valve which drops it by 1.7 psi per 1 psi of manifold depression.

They are both variable pressure regulators, they each have a constant rate (NOT rising rate), the rates are different.

I think you may misunderstand two things; the dynamics of fueling in high demand situations and the fact that these thingies come in many models for different fueling systems. A Hotwire FSE and a Flapper FSE are not the same. I have never seen a problem with either installation.

That being said, I do NOT suggest that the reasons for buying one for a Hotwire are as weighty. I made that clear in my first epistle. If you are buying one ONLY to better your Hotwire's reaction when you floor it, don't bother unless you are a rallyist on steroids.

However, if you look at the cost of your stock fuel pressure regulator (ETC8494 = £75.12), a standard fuel pressure tester (£65 Halfords) and today's shop time costs (£45/hr+) , then £75 for a FSE/gauge kit is a bargain ..assuming you plan to keep the car.

racer

[r2d2hp]

When my car was setup by Mark Adams he advised I did not need one.

[racer]

When my car was setup by Mark Adams he advised I did not need one.

What fueling system do you have?

racer

[r2d2hp]

Low Pressure pump from tank to swirl pot, High pressure from swirl pot to Fuel rail which then return via standard fuel regulator back to the tank.

Engine is standard Rover 4.3 but now has supercharger fitted and now needs to be remapped.

With the supercharger came this device >> http://neptune.spacebears.com/cars/stories/scfmu.html

but I have not fitted it yet, do you think I should fit this in place of the standard regulator.