The FSE - Adjustable Fuel Pressure Regulator - How / What / Where

This is going nowhere.

Paul, do a power run with a stock FPR & and FSE and post the curves, better still the AFR readings.

Ian, the reason for changing the stock out would be higher flowing units. I am not sure how the stock would cope having two pumps firing at it. I have a -6 Aeromotive one BTW.

Originally posted by Terry S

This is going nowhere.

 

Paul, do a power run with a stock FPR & and FSE and post the curves, better still the AFR readings.

 

Ian, the reason for changing the stock out would be higher flowing units. I am not sure how the stock would cope having two pumps firing at it. I have a -6 Aeromotive one BTW.

Agreed. A back-to-back dyno run would sort this out, especially with the fuelling results. On a stock Supra as well, as these ones are apparently for responsiveness, rather than additional top end fuelling.

Yeah, the stock FPR needs swapping out once you go mad, agreed I'll be going for something like that Aeromotive one I believe.

-Ian

Originally posted by Terry S

This is going nowhere.

 

Paul, do a power run with a stock FPR & and FSE and post the curves, better still the AFR readings.

 

I agree - going nowhere

Have spoken to Pete at Thor - and he will have some results in a couple of weeks - with a Celica to which one is being fitted and also to his own car -

I have asked him to let us have some results

Stock on his

FSE at stock fuel rail

FSE at higher Rail pressure

However not sure it will make a difference Terry

She's a witch...

Throw her in..

If she floats she's a witch - and we burn her!

If she sinks she's not a witch!

Oooo...now there's a challenge!

its so confusing hearing different thoughts on this matter. would it only be worth doing if you going with a bigger injectors or full kit. as the jap fuel system must be close to the edge on bpu+

would fitting an uprated fuel pump be wasted without a fpr.

seems a lot of people have them fitted to bpu+ cars

what do all the big power cars run with?

just curious.

have a look here for loads of FPR`s

http://horsepowerfreaks.com/ShowProductsMain.asp?ModelCd=SUP4&SubCategoryCd=FPRE

lots of fueling parts here, never seen so many items

http://horsepowerfreaks.com/ShowSubcategories.asp?CategoryCd=FUEL&ModelCd=SUP4&CategoryDesc=Fuel+Components

Originally posted by MONKEYmark

its so confusing hearing different thoughts on this matter. would it only be worth doing if you going with a bigger injectors or full kit. as the jap fuel system must be close to the edge on bpu+

would fitting an uprated fuel pump be wasted without a fpr.

seems a lot of people have them fitted to bpu+ cars

 

The FSE is NOT a substitute for a properly upgraded fuelling system

There is no problem with upgrading your fuel pump solely

It is great if you have jap spec injectors and add an uprated fuel pump (Uk or Walbro) and 12V mod relay (if you have a walbro particularly)

Originally posted by Ian C

How, I wonder, does this mechanical device provide a 1.7:1 increase in fuel pressure when off boost and only a 1:1 increase when on boost? There is one adjusting screw, there is one vacuum reference pipe, and there is one internal diaphragm.

 

I'm rather convinced that the FSE valve in fact increases fuel rail pressure by 1.7:1 all the time. This is why people use them on 440cc injectors, to up the fuel pressure and deliver a bit more fuel when on-boost.

 

Paul, your initial posts credit who said what apart from the first one which assures us that the FSE Power Boost Valve isn't a rising rate regulator. Is that from FSE themselves? It reads like a sales pitch, there are a few things I don't buy at all in that.

 

-Ian

Ian , you keep quoting the figure of 1.7:1 when i think the figure is 1.17:1 , there is a slight difference !!!!!!!

Dude:flame Dev

I'm sure there's a lot of people with both cats out, running 18psi or whatever that want some sort of safety net way of getting a bit more fuel at high boost past the end of the stock fuel map, as a stop gap until they upgrade further with bigger injectors/fuel computers etc with all the associated costs. What's the best way of doing this? Fuel pump alone, pump + FSE, or don't bother?

The conclusion I'm coming too reading all this is that there's no substitute for getting on a rolling road and checking what's going on with the fueling, which I think is what I'll do after fitting my Walbro, FMIC & taking the 2nd cat out.

Originally posted by Ian C

Paul, I think that under racing conditions engines are tuned so close to death that accuracy and longevity are huge considerations as one slip = blown engine and lost race rather than running a bit rough. I wouldn't call tweaking a stock FPR a 'fudge' when the word 'tweaking' is used in a race engineering context either.

 

Chris - how many race engines have you seen using FSE valves for improved responsiveness?

 

-Ian

None. Why should it give "improved responsiveness" Toyota spent months mapping the engine, why would increasing line pressure give improved responsiveness? It's like saying they haven't mapped it right, it needs more fuel to remove hesitations... Rubbish :)

Originally posted by Chris Wilson

None. Why should it give "improved responsiveness" Toyota spent months mapping the engine, why would increasing line pressure give improved responsiveness? It's like saying they haven't mapped it right, it needs more fuel to remove hesitations... Rubbish :)

But how many have got stock motors as Mr Toyota intended ??? not many and none with an FSE , why not wait till Thors dyno results or someone may have egg on their face !!!!

Dude:flame Dev

Dude,

The point of it is to richen up the mixture via more fuel pressure, yes?

Rich mix = less power. If it does what it says, power and response will suffer, although some think it would be safer with the rich mixture.

Personally, I don't see why it is needed. Supras run rich even when decatted etc. So why richen up the mix even more? Unless trying something silly like hybrids and 440s etc.

Unless I have got something wrong?

Can we all just wait for some power runs to be published. I must say that I have personally seen some really nice power curves with FSE's, but it needs to be compared with stock FPR on the same car, say day, same fuel, same boost etc etc.........

Not that I really want to get involved in this thread, but I just wanted to add that my previous car, (the red auto), used to run lean at about 1.25 bar. You could actually hear det from the engine if WOT was sustained for any length of time. (no hybrids, just stock fuelling & stock turbos).

I went to Leon for his advice, and he fitted a Walbro pump and FSE regulator. i have no idea what he set it up to, but from that day on, I could run 1.3 without det problems, and did so on many track days/top speed runs etc.

I also attended 2 entirly different rolling roads, and both produced perfect fuel curves...

Now, I don't know if it was simply the uprated pump that cured the problem, or a combination of the pump and the FSE, but I certainly had no problems 'caused' by using an FSE.

I agree with Terry, let's wait for Pete to run a couple of tests and see what the results are...

Personally, I don't see why it is needed. Supras run rich even when decatted etc. So why richen up the mix even more? Unless trying something silly like hybrids and 440s etc.

A bit of sweeping statement there Syed , ask Matt B to send you his Thor Dyno sheet of his car (fairly stock) with a walboro pump and then tell me they normally run rich !!!!!

Dude:flame Dev

Originally posted by dude

Ian , you keep quoting the figure of 1.7:1 when i think the figure is 1.17:1 , there is a slight difference !!!!!!!

 

Dude:flame Dev

There is a reason I keep quoting the 1.7:1 figure:

http://www.fuelsystem.co.uk/pbv.htm

This is FSE themselves. They say:

Supra Turbo 3.0i

05/93>

VK-384-TOY1-H

£98.00

"On acceleration from standstill the Power Boost Valve fuel pressure will increase at 1.7 times the standard rate."

They also sell a "FUEL INJECTION (ADJUSTABLE BASE PRESSURE) 1:1 REGULATOR" (http://www.fuelsystem.co.uk/regulators.htm) Interestingly their website offers it for £40, less than half the cost of an PBV. It's an entirely different bit of kit to the Power Boost Valve, it's just an FPR.

Random sales blurb from a.n.other tuning company:

http://www.rpw.com.au/Products/Fuel%20Products/FSE%20FPR%20units.htm

"On acceleration from standstill the Power Boost Valve fuel pressure will increase at 1.7 times the standard rate. This will produce a healthy, strong fuel mixture strength which will instantly improve the drivability of your vehicle"

" When you have done any turbo conversion or planning on doing so, the rising rate unit means it also increases fuel pressure an additional 1.7 psi for every 1 psi of boost. "

And finally:

http://www.miami-rice.com/index2.html

"FSE

£115.00

PBV (power boost valve) its a rising rate regulator thats adjustable and increases the fuel pressure as manifold pressure increases "

So, the FSE Power Boost Valve is a rising rate regulator that increases fuel pressure by 1.7:1 as boost rises. So it does affect the fuelling when under boost. I don't care if they 'fix' an inadequate fuel system or not, I'm not using one anymore - the point to all this is the initial posting about what a power boost valve is, isn't, and what it does, was incorrect. Dunno why people are getting so arsey about it.

-Ian

Originally posted by dude

 

A bit of sweeping statement there Syed ,

Im good at those

Seriously, MOST BPU cars run rich. Unless you have logged AF ratios showing an uncomfortably lean reading, there is no need. I would not run one unless setup for proper AF ratios. Nothing wrong with them if needed to cure lean condition and setup using a wideband.

Got to back Dude up there, my car was running very lean after being de-catted and the boost levels rising. I had the Walbro pump fitted but when it wason the dyno at the Jap show it was not good news. Having since had the FSE fitted and returned to Pete's for another run I'm told it's now running fine if a little rich.

Must agree though, when it was running lean it did feel a lot quicker. When I picked it up from Thor's it felt a little slower but I was happy enough with this as I knew the engine was safe from damage.

Cheers

I think it's fair to say the UK BPU cars may still run rich, but the J-spec's don't.

Remove the cats and up the boost and a JDM car is on borderline almost instantly. (depending on your boost level, I'm basing this on 1.2+). It's rare to find a JDM car running rich at high boost unless the fueling has been altered. In fact, from what I've seen, quite the opposite.

*** Please don't turn this into a UK vs J-spec thing, we all know the UK has better fuelling as standard ***

Originally posted by Matt Harwood

*** Please don't turn this into a UK vs J-spec thing, we all know the UK has better fuelling as standard ***

Doesn't make em any faster thought does it?

Originally posted by Matt Harwood

*** Please don't turn this into a UK vs J-spec thing, we all know the UK is better as standard ***

OI, you two...

Heres JOHNNY !!!!!!

Dude:flame Dev

So if you have a de-catted J-Spec running 1.2 boost a little lean you should get a Walbro correct?

And the FSE needs to go with the pump or not really needed? Is that right.

I'm asking not stating!

Thanks

J.

Originally posted by Justin

So if you have a de-catted J-Spec running 1.2 boost a little lean you should get a Walbro correct?

 

And the FSE needs to go with the pump or not really needed? Is that right.

 

I'm asking not stating!

 

Thanks

 

J.

Some say yes some say no but Pete Betts at THOR is gonna do a step by step Dyno 'experiment ' using his car with and without the FSE , there will be no arguing with the results and THEN would be the time to make up your mind , personally i have one and love it my car made 380 at the hubs and 404 ft lb on Petes dyno with good fueling so i will be leaving mine on !!!!

Dude:flame Dev

Justin,

I think the general conscensous (sp?) is that (at 1.2 bar) a warlbro or any uprated fuel pump will help, and should be on the list of mods to do for a J-spec as a matter of course.

The FSE will put more fuel into the engine, but is not the ideal set-up. Ideally you'd get larger injectors, and all the tom-foolery that goes with them to set them up correctly (fuel computers and the like)

However watch this space for the complete answer....

Regards

My BPU J Spec runs lean at 1.2 bar.