Fuel, fuel, fuel.

[t3ase]

Alright, I was running 14psi for months on the MSP and finally got the balls to go all out at 18psi before, what I think anyway, spinning a rod bearing. Now, during the times of 14psi, I had the Walbro Miata GSS342 pump installed. However, I ran the MSP literally out of gas and had issues with fuel delivery after that so the stocker went back in during troubleshooting. I forgot that it was in there after time and then the 18psi came. Needless to say, my car's been inactive since then.

Anyway, question is, even with stock injectors, was that pump even doing anything? Sure it could provide more fuel but isn't it up to the injectors how much actually gets in to the mix? Should I switch back to the Walbro even with stock injectors when the car's up again?

[t3ase]

Alright, I was running 14psi for months on the MSP and finally got the balls to go all out at 18psi before, what I think anyway, spinning a rod bearing. Now, during the times of 14psi, I had the Walbro Miata GSS342 pump installed. However, I ran the MSP literally out of gas and had issues with fuel delivery after that so the stocker went back in during troubleshooting. I forgot that it was in there after time and then the 18psi came. Needless to say, my car's been inactive since then.

Anyway, question is, even with stock injectors, was that pump even doing anything? Sure it could provide more fuel but isn't it up to the injectors how much actually gets in to the mix? Should I switch back to the Walbro even with stock injectors when the car's up again?

[greendragon]

Not knowing much about trbos and the fuel needed , I would think that the extra PSi from the pump would allow more fuel in under higher pressure , ie if you have a certian size hole in a sealed container and you send fluid through at say 20 psi for 1 min. then using the same hole at 40 psi for the same time ,I think you will find that the 40 psi will have more fluid in the contaniner . I hope this makes sense .

[greendragon]

Not knowing much about trbos and the fuel needed , I would think that the extra PSi from the pump would allow more fuel in under higher pressure , ie if you have a certian size hole in a sealed container and you send fluid through at say 20 psi for 1 min. then using the same hole at 40 psi for the same time ,I think you will find that the 40 psi will have more fluid in the contaniner . I hope this makes sense .

[t3ase]

True, I didn't think about it that way.

Kinda the "poke a small hole in a water glass at a high spot and then a low spot and see the pressure differences" kinda deal. The size is the same but more is exiting the hole.

[t3ase]

True, I didn't think about it that way.

Kinda the "poke a small hole in a water glass at a high spot and then a low spot and see the pressure differences" kinda deal. The size is the same but more is exiting the hole.

[Ken@ProtegeGarage]

stock fuel pressure on a protege is about 35 psi at idle. with the walbro intank, fuel pressure at idle hits about 45 to 50 psi. i would not recommend the stock pump for applications on the protege that require more gas (ie - boost). the pump is the same as in the 2nd generation miata and are known to frequently burn out on the MSM as well. i have burned out two.

that being said, your ECU will not know how to handle the extra fuel pressure and will do little to nothing to tune around it. in order to really utilize its extra flow, you will need engine management.

[Ken@ProtegeGarage]

stock fuel pressure on a protege is about 35 psi at idle. with the walbro intank, fuel pressure at idle hits about 45 to 50 psi. i would not recommend the stock pump for applications on the protege that require more gas (ie - boost). the pump is the same as in the 2nd generation miata and are known to frequently burn out on the MSM as well. i have burned out two.

that being said, your ECU will not know how to handle the extra fuel pressure and will do little to nothing to tune around it. in order to really utilize its extra flow, you will need engine management.

[505zoom]

Yea, geez man, no tuning and you were going for 18psi?... shame on you. The pump will raise the pressure PRE injectors and allow you to flow more out of them *only if you are tuning for it*. That pump was doing nothing to add more fuel into the cylinders at all on your old setup.

And in all honesty, the stock pump has held up fine for me for a very long time now running 275-300whp. Much more than that though, and I think it probably won't cut it anymore.

[505zoom]

Yea, geez man, no tuning and you were going for 18psi?... shame on you. The pump will raise the pressure PRE injectors and allow you to flow more out of them *only if you are tuning for it*. That pump was doing nothing to add more fuel into the cylinders at all on your old setup.

And in all honesty, the stock pump has held up fine for me for a very long time now running 275-300whp. Much more than that though, and I think it probably won't cut it anymore.

[BRIAN MP5T]

15 PSI is One Bar

One Bar Is Double The Air

Double The Air Requires Double The Volume Of Fuel..

You Were Running 18 PSI...

[BRIAN MP5T]

15 PSI is One Bar

One Bar Is Double The Air

Double The Air Requires Double The Volume Of Fuel..

You Were Running 18 PSI...

[t3ase]

yes, I've heard the speeches.

so for fuel, without management at this time, how about:

larger 440 injectors + rising rate FPR + walbro gss340 pump

would *that* help even with stock management?

[t3ase]

yes, I've heard the speeches.

so for fuel, without management at this time, how about:

larger 440 injectors + rising rate FPR + walbro gss340 pump

would *that* help even with stock management?

[t3ase]

14.75 is technically a bar, also. :D

[t3ase]

14.75 is technically a bar, also. :D

[pdhaudio83]

werd, i am running the stock pump *KNOCK ON WOOD* (but the same pressure, AFAIK)

[pdhaudio83]

werd, i am running the stock pump *KNOCK ON WOOD* (but the same pressure, AFAIK)

[BRIAN MP5T]

14.75 is technically a bar, also. :D


Blow Me. :)

[BRIAN MP5T]

14.75 is technically a bar, also. :D


Blow Me. :)

[t3ase]

Blow Me. :)
mmmmmmmmm, you have pm, big boy. (naughty)

[t3ase]

Blow Me. :)
mmmmmmmmm, you have pm, big boy. (naughty)

[505zoom]

yes, I've heard the speeches.

so for fuel, without management at this time, how about:

larger 440 injectors + rising rate FPR + walbro gss340 pump

would *that* help even with stock management?

How do you plan to tune the idle for the 440's with a FPR?

[505zoom]

yes, I've heard the speeches.

so for fuel, without management at this time, how about:

larger 440 injectors + rising rate FPR + walbro gss340 pump

would *that* help even with stock management?

How do you plan to tune the idle for the 440's with a FPR?

[t3ase]

eh? I haven't ever played with fuel before, so I dunno. I was assuming the rising rate regulator + stock ecu would handle idle conditions and the rising aspect would handle load.

[t3ase]

eh? I haven't ever played with fuel before, so I dunno. I was assuming the rising rate regulator + stock ecu would handle idle conditions and the rising aspect would handle load.

[505zoom]

Nope, you can't run bigger than stock injectors without something like DSM's AFC, emanage, and all the big boys. If you want cheap, go with the DSM + 440's, or go with a extra injector controller and some pre-TB secondaries like I am running.

[505zoom]

Nope, you can't run bigger than stock injectors without something like DSM's AFC, emanage, and all the big boys. If you want cheap, go with the DSM + 440's, or go with a extra injector controller and some pre-TB secondaries like I am running.

[Ken@ProtegeGarage]

injectors work by pulse time. the ecu or the engine management tells the injectors how much fuel to "pulse" into the manifold depending on engine load variables such as manifold pressure and RPM. the larger injectors flow more fuel, so for example a 190cc injector pulsing the same "time" as a larger 440cc injector will not flow as much fuel. its like two water hoses, one large and one small, that are both under the exact same water pressure. obviously the larger hose is going to spray more water regardless of the fact that both hoses have the same pressure.

[Ken@ProtegeGarage]

injectors work by pulse time. the ecu or the engine management tells the injectors how much fuel to "pulse" into the manifold depending on engine load variables such as manifold pressure and RPM. the larger injectors flow more fuel, so for example a 190cc injector pulsing the same "time" as a larger 440cc injector will not flow as much fuel. its like two water hoses, one large and one small, that are both under the exact same water pressure. obviously the larger hose is going to spray more water regardless of the fact that both hoses have the same pressure.

[BRIAN MP5T]

^^^ What he said. Basically the FMU and the Stock Injectors work well, Larger injectors leave you PIG righ all the time.

Here is another cheap way..

http://www.sdsefi.com/eic.html

[BRIAN MP5T]

^^^ What he said. Basically the FMU and the Stock Injectors work well, Larger injectors leave you PIG righ all the time.

Here is another cheap way..

http://www.sdsefi.com/eic.html

[t3ase]

so basically stay with stock until I can afford management.

[t3ase]

so basically stay with stock until I can afford management.

[t3ase]

and it's not that i *WANT* cheap, i've just been unemployed for about three months and carless for about a year and a half. i surely don't want to end up this way again, so I'm trying to get the "safety net" things out of the way.

[t3ase]

and it's not that i *WANT* cheap, i've just been unemployed for about three months and carless for about a year and a half. i surely don't want to end up this way again, so I'm trying to get the "safety net" things out of the way.

[BRIAN MP5T]

EIC-2

$400.00,

I have run it for 3 Years..

[BRIAN MP5T]

EIC-2

$400.00,

I have run it for 3 Years..

[t3ase]

what about fuel rails? are they needed?

[t3ase]

what about fuel rails? are they needed?

[BRIAN MP5T]

what about fuel rails? are they needed?

Why..

Stock Fuel system on the Intake, 2 Extra injectors before the TB..

Look Bottom Right


http://memimage.cardomain.net/member_images/11/web/503000-503999/503974_181_full.jpg

[BRIAN MP5T]

what about fuel rails? are they needed?

Why..

Stock Fuel system on the Intake, 2 Extra injectors before the TB..

Look Bottom Right


http://memimage.cardomain.net/member_images/11/web/503000-503999/503974_181_full.jpg

[t3ase]

MAM's got three stages of fuel system upgrades, and I know the first one at least has the rail.

When does that become a priority?

[t3ase]

MAM's got three stages of fuel system upgrades, and I know the first one at least has the rail.

When does that become a priority?

[BRIAN MP5T]

MAM's got three stages of fuel system upgrades, and I know the first one at least has the rail.

When does that become a priority?

When you are relying on the rail to deliver the added fuel for the turbo.

For mine at least, it's not required cause I still have the stock Injectors feeding the engine up to -1Vac. After that the EIC starts upping the fuel in conjunction witht he stock.

Basically, the injectors are your major concern for higher boost.The fuel rail is great, but think about what's going on with the fuel lines. The Rail can be 4 Feet in diameter, if the fuel line is still small then what's the point. Bling?

I don't know how much of an gain you are really getting without the fuel lines being changed.

Beau "In Hiding" would be the better to ask.

[BRIAN MP5T]

MAM's got three stages of fuel system upgrades, and I know the first one at least has the rail.

When does that become a priority?

When you are relying on the rail to deliver the added fuel for the turbo.

For mine at least, it's not required cause I still have the stock Injectors feeding the engine up to -1Vac. After that the EIC starts upping the fuel in conjunction witht he stock.

Basically, the injectors are your major concern for higher boost.The fuel rail is great, but think about what's going on with the fuel lines. The Rail can be 4 Feet in diameter, if the fuel line is still small then what's the point. Bling?

I don't know how much of an gain you are really getting without the fuel lines being changed.

Beau "In Hiding" would be the better to ask.

[Aric]

A new fuel rail is just eye candy and probably not NEED upgrading untill 400+ horsies.
You wouldnt really need one untill you cannot push enough volume through it.
So you would run 440cc injectors and if those are not enough you can up the preasure with a regulator, if thats not enough you need to overhaul everything. New larger fuel lines from the tank all the way to the front of the car.
And at that point the car would be something to take to the track on a trailer.

I suggest walboro intank with a BEGi rising rate FPR and a wideband O2 gauge. But if you are going to go the whole built engine route just wait for a full standalone.

[Aric]

A new fuel rail is just eye candy and probably not NEED upgrading untill 400+ horsies.
You wouldnt really need one untill you cannot push enough volume through it.
So you would run 440cc injectors and if those are not enough you can up the preasure with a regulator, if thats not enough you need to overhaul everything. New larger fuel lines from the tank all the way to the front of the car.
And at that point the car would be something to take to the track on a trailer.

I suggest walboro intank with a BEGi rising rate FPR and a wideband O2 gauge. But if you are going to go the whole built engine route just wait for a full standalone.

[pdhaudio83]

but wait, i dont think the stock fuel pump will have to push much harder if im holding stock PSI with a slightly bigger injector (440) thoughts?

[pdhaudio83]

but wait, i dont think the stock fuel pump will have to push much harder if im holding stock PSI with a slightly bigger injector (440) thoughts?

[Aric]

stock PSI on different injectors is probably OK, but you might run into problems with volume. Anyone know how to calculate fuel use/needs for 440cc injectors?

The miata walboro pump is a direct drop in, the RX7 pump flows more but needs some screwing around and cutting but is a pretty good fit.

[Aric]

stock PSI on different injectors is probably OK, but you might run into problems with volume. Anyone know how to calculate fuel use/needs for 440cc injectors?

The miata walboro pump is a direct drop in, the RX7 pump flows more but needs some screwing around and cutting but is a pretty good fit.

[Ken@ProtegeGarage]

but wait, i dont think the stock fuel pump will have to push much harder if im holding stock PSI with a slightly bigger injector (440) thoughts?
the stock pump period is really no good for boost above the equivalent of 8psi on a t3. this has been verified by the boys at FM.

[Ken@ProtegeGarage]

but wait, i dont think the stock fuel pump will have to push much harder if im holding stock PSI with a slightly bigger injector (440) thoughts?
the stock pump period is really no good for boost above the equivalent of 8psi on a t3. this has been verified by the boys at FM.

[BRIAN MP5T]

stock PSI on different injectors is probably OK, but you might run into problems with volume. Anyone know how to calculate fuel use/needs for 440cc injectors?

The miata walboro pump is a direct drop in, the RX7 pump flows more but needs some screwing around and cutting but is a pretty good fit.


I swapped out for the larger fuel pump.

It's possible the the stock will work well, but it will eventually fail sooner from the added load beyond it's design.

[BRIAN MP5T]

stock PSI on different injectors is probably OK, but you might run into problems with volume. Anyone know how to calculate fuel use/needs for 440cc injectors?

The miata walboro pump is a direct drop in, the RX7 pump flows more but needs some screwing around and cutting but is a pretty good fit.


I swapped out for the larger fuel pump.

It's possible the the stock will work well, but it will eventually fail sooner from the added load beyond it's design.

[Peepsalot]

Not knowing much about trbos and the fuel needed , I would think that the extra PSi from the pump would allow more fuel in under higher pressure , ie if you have a certian size hole in a sealed container and you send fluid through at say 20 psi for 1 min. then using the same hole at 40 psi for the same time ,I think you will find that the 40 psi will have more fluid in the contaniner . I hope this makes sense .
I'm pretty sure there's a fuel pressure regulator built in to the stock setup that only lets a certain pressure go to your injectors. I don't think supplying more fuel from the pump will change your tune at all, because the regulator will keep it in check.

[Peepsalot]

Not knowing much about trbos and the fuel needed , I would think that the extra PSi from the pump would allow more fuel in under higher pressure , ie if you have a certian size hole in a sealed container and you send fluid through at say 20 psi for 1 min. then using the same hole at 40 psi for the same time ,I think you will find that the 40 psi will have more fluid in the contaniner . I hope this makes sense .
I'm pretty sure there's a fuel pressure regulator built in to the stock setup that only lets a certain pressure go to your injectors. I don't think supplying more fuel from the pump will change your tune at all, because the regulator will keep it in check.

[Aric]

I'm pretty sure there's a fuel pressure regulator built in to the stock setup that only lets a certain pressure go to your injectors. I don't think supplying more fuel from the pump will change your tune at all, because the regulator will keep it in check.
the stock regulator is pretty dumb, it can only limit the pressure so much. Think of it like this, you have a tube with a small hole in it and you are blowing air into the tube, the harder you blow the air will come out faster but only so much air can get through that hole before you start to build more pressure in that tube.

[Aric]

I'm pretty sure there's a fuel pressure regulator built in to the stock setup that only lets a certain pressure go to your injectors. I don't think supplying more fuel from the pump will change your tune at all, because the regulator will keep it in check.
the stock regulator is pretty dumb, it can only limit the pressure so much. Think of it like this, you have a tube with a small hole in it and you are blowing air into the tube, the harder you blow the air will come out faster but only so much air can get through that hole before you start to build more pressure in that tube.

[t3ase]

and then your car explodes from built up fuel pressure.

[t3ase]

and then your car explodes from built up fuel pressure.

[NSNMotorsports]

Big injectors and small injectors run surprsingly similar injection open times at idle... has to do with the atomization and efficiencies of the injectors... I've typically seen that it's less than a half ms different at idle between a 550 and a 280... and while a half ms is about 30% different at idle... that doesn't match the difference between the injectors etc..

The "ideal" setup to go with for fuel is dual rails with smaller primaries and larger secondaries.. you get more cooling affect that way and a cleaner atomization at the ports...

[NSNMotorsports]

Big injectors and small injectors run surprsingly similar injection open times at idle... has to do with the atomization and efficiencies of the injectors... I've typically seen that it's less than a half ms different at idle between a 550 and a 280... and while a half ms is about 30% different at idle... that doesn't match the difference between the injectors etc..

The "ideal" setup to go with for fuel is dual rails with smaller primaries and larger secondaries.. you get more cooling affect that way and a cleaner atomization at the ports...

[NSNMotorsports]

Keep in mind guys that providing ENOUGH fuel is not all that you need to do... providing GOOD fuel and cool air goes a long ways... that is why I'm happy to have two rails.. I don't run my secondary rail yet as the 550 primaries have been enough to keep it going so far, but this summer when I go to 25 psi I will need the secondary rail... and when I do that I'll move the 300 cc injectors to primary position and put the 550s in secondary... that way I'll get improved tract charging etc... I've heard/read that in some formula cars they run a secondary bank as the very beginning of the intake runners because of the superior vapor charging...

[NSNMotorsports]

Keep in mind guys that providing ENOUGH fuel is not all that you need to do... providing GOOD fuel and cool air goes a long ways... that is why I'm happy to have two rails.. I don't run my secondary rail yet as the 550 primaries have been enough to keep it going so far, but this summer when I go to 25 psi I will need the secondary rail... and when I do that I'll move the 300 cc injectors to primary position and put the 550s in secondary... that way I'll get improved tract charging etc... I've heard/read that in some formula cars they run a secondary bank as the very beginning of the intake runners because of the superior vapor charging...

[pdhaudio83]

Ah yes Steve, 550s. You have those available at all?

[pdhaudio83]

Ah yes Steve, 550s. You have those available at all?

[NSNMotorsports]

Yes and no... I can get the ones that I have I think... but you can use other ones off the shelf... but all require spacers and different connectors to be used. I would just get the RC550's and work from there...

One benefit to the Microtech and how I get to run things is I wire the injectors together in parallel on each channel so my secondary and primary fire as one... the drivers in the Microtech are big enough to that unlike others :)... and I can even do that with 2 low impedance injectors as well as mixing and matching high and low etc. :)

[NSNMotorsports]

Yes and no... I can get the ones that I have I think... but you can use other ones off the shelf... but all require spacers and different connectors to be used. I would just get the RC550's and work from there...

One benefit to the Microtech and how I get to run things is I wire the injectors together in parallel on each channel so my secondary and primary fire as one... the drivers in the Microtech are big enough to that unlike others :)... and I can even do that with 2 low impedance injectors as well as mixing and matching high and low etc. :)

[pdhaudio83]

:p

I am still interested the Microtech at some point, I'm still learning more and more about the Haltech too though.

[pdhaudio83]

:p

I am still interested the Microtech at some point, I'm still learning more and more about the Haltech too though.

[Ken@ProtegeGarage]

pat i think at where you are currently at, the haltech is a good setup for you

[BRIAN MP5T]

The "ideal" setup to go with for fuel is dual rails with smaller primaries and larger secondaries.. you get more cooling affect that way and a cleaner atomization at the ports...

Basically, the EIC-2 that I run makes me very happy because of this "Cooling" effect, Money in the bank. I was thinking about the EIC-4 and running one injector per runner. I fear that the injectors being at the TB and not at the intake valve is a bit far..

I understand what you are saying about the injector size not being the root of poor idle, as long as the injectors are capable of atomization.

Did anyone ever bother to find out where the stock injectors on the MSP stop being able to keep up with boost? Like 10 Psi or is it lower?

When I first had the MP5T together I ran the Tial at 4 Psi on totally stock fuel delivery and it would run lean. 4 Psi is not alot of diference which is why I wonder if all these Boom threads were mostly caused because of MBC and No Fuel Delevery upgrades. A FMIC will help detonation, but will not magically fix a lean condition.

[Jeph]

So unless you have larger fuel lines running all the way from the tank a larger rail won't make a difference? Wouldn't the larger rail be able to hold more fuel for delivery even if the lines aren't any bigger between it and the tank?

[NSNMotorsports]

Yeah, pat if you already have a standalone and you are happy running it you aren't going to gain anything really by going Microtech etc... other than my help and some of the benefit of my maps and so forth. If Ken is shitting a brick with joy over the Microtech in 3 or 4 months and says it is the bomb compared to the Haltech, then think about it... but otherwise I'd stick with the Haltech if you have it already unless you start having problems.

[NSNMotorsports]

So unless you have larger fuel lines running all the way from the tank a larger rail won't make a difference? Wouldn't the larger rail be able to hold more fuel for delivery even if the lines aren't any bigger between it and the tank?

The fuel system works partially on the principle that the pump provides way more fuel than is used so it recirculates back to the fuel tank all the time... the rail is really a resevoir... put it this way... I'm running 550's on the stock rail without any issue... so I wouldn't worry a lot about the rail needing to be upgraded... a bigger rail can in theory level out pressure differentials and some other issues, but isn't anything of major significance in any way.

[Jeph]

Ok, but to use the stock rail, and bigger injectorrs, you have fitment issues with the injectors, the rail, and the IM, so the only real benefit to haveing the new rail is not having to make spacers to get the bigger injectors to fit right?
heh, long sentence...

[NSNMotorsports]

yeah more or less that covers it.. makes it easier to use braided line and fit a different reg if you need to as well...

[Jeph]

Yeah, I'll have a new FPR, lines, and injectors :)
THey are sitting in my room just waiting to be installed