Unique: Throttle Bodies|Intake Plenum and Manifold

MADFTO · Post by **MADFTO** » Fri Aug 20, 2004 6:15 pm

*laughs* I didn't even try =)

mine's set to 5.7 at the moment, gives a smoother changeover for me, not much else different =)

GWIDO · Post by **GWIDO** » Tue Sep 07, 2004 4:50 pm

well there seems to a lot of confusion about FPR's here so lets see if i can make it worse...
more air requires more fuel to maintain the same mixture.
So extractors, downpipes or throttle body will require more fuel to be supplied to maintain mixture.
Rising fpr increases pressure in the rail which in turn allows more fuel to flow through the injector( they can flow upto 300% of factory i think).
As extra air goes in the car starts to lean, Oxygen sensor detects this and changes injector rate to get correct mixture. With stock fuel system this would mean the open pulse would be longer. with increased fuel pressure this would mean the pulse would be the same, just the fuel flow rate would be higher.
keep increasing airflow and eventually you get to a point where the injector cannot stay open for long enough and so you have to increase flow.
the point of the rising rate regulator is to supply more fuel as it is needed, instead of just having that pressure there all the time, less load, less wear and tear.
Now its up to you whether you need it or not.
Standard idle pressure is around 38psi for whoever asked, about 42 is good with mods...
I've found the car has flat spots at about 36psi (i think it was), but this is still with rising rate so actually supplying fuel at about 55psi at what. So with stock system, delivering about 38psi pressure (idle and what) and intake/exhaust mods you are gonna have trouble.
Now its still up to you whether you need it or not.

G_A_V · Post by **G_A_V** » Tue Sep 07, 2004 5:24 pm

ok i may be consfusing people even more, but i always thought that a fpr keeps fuel pressure on standby for when you first hit what, giving better throttle responce, though im prob wrong

ruchi · Post by **ruchi** » Tue Sep 07, 2004 5:57 pm

WTF!

GWIDO wrote:well there seems to a lot of confusion about FPR's here so lets see if i can make it worse...

I think you succeeded

GWIDO wrote:So extractors, downpipes or throttle body will require more fuel to be supplied to maintain mixture.

The only item that requires more fuel to keep the air/fuel ratio the same when airflow increases is the cyclinders

GWIDO wrote:Rising fpr increases pressure in the rail which in turn allows more fuel to flow through the injector( they can flow upto 300% of factory i think).

WTF!

ummm... no! Most cars injectors will be running at around 80% capacity (give or take a little).

GWIDO wrote:keep increasing airflow and eventually you get to a point where the injector cannot stay open for long enough and so you have to increase flow.

Yes, but the mods required to reach this point are quite extreme and well beyond what most people ever do.

GWIDO wrote:I've found the car has flat spots at about 36psi (i think it was)

Sounds like you're getting brainwashed by RPW

GWIDO wrote:So with stock system, delivering about 38psi pressure (idle and what) and intake/exhaust mods you are gonna have trouble.

um, no. With the exception of forced induction, you'd need a lot more than the standard intake and exhaust mods most people have done before your injectors or FPR would need upgrading.

G_A_V · Post by **G_A_V** » Tue Sep 07, 2004 7:11 pm

settle down ruchi, he is just relaying what he thinks, no need to critisize

Post by **smorison** » Wed Sep 08, 2004 9:29 am

ruchi: told you your explaination would confuse people

lol

gwido: i'm not sold on the FPR yet... when we finish the mivec cams we'll be putting all this on my car... whilst doing that we will be sonic cleaning and flowbenching the injectors to see where they are at. We will also put them in and test duty cycles and other tests to ensure that with the mods there are no leaning out issues...

if you are experiencing flat spots i would suggest that your fuel filters are very dirty (including the pickup filter) or the Fuel pump is on its way out...

the TB and intake mods will probably allow upto 25% more air to FLOW ... that isn't necessarily 25% more air DELIVERED to the cylinders (this distinction is very important) my testing at the moment shows that i'm running between 1 to 3mm (mecury) of restrictions through the intake system... (depends on air temp and car speed)... so our mods todate are working pretty damn well... the new mods should help flow and it would be really nice to see it change for a pressure of -3mm to a positive figure (car on boost when pressure is positive).

ruchi · Post by **ruchi** » Wed Sep 08, 2004 10:04 am

smorison wrote:ruchi: told you your explaination would confuse people lol

LOL!

geez, I said the figures were for "example" and "not accurate or indicative of real-world situations". But I tell you what, 300% headroom would make it real easy for mods!

MADFTO · Post by **MADFTO** » Wed Sep 08, 2004 11:27 am

Just a quick note . . .

All the FPR does is to adjust the baseline fuel rail pressure and to increase the fuel pressure threshold as the RPMs are increasing if you've got one that does increasing rate.

Pressure can only build up if there is resistance for the pressure to build, now there shouldn't be a point where the regulator stops needing to return fuel to the tank and actually allow all the fuel to be piped into the rail because the needs of the fuel system match or overtake the fuel pump's flow rate to provide that fuel. However, the pressure in the rail is to allow for sudden changes in fuel system demand towards positive, as the RPMs climb, there should be less emphasis on pressure and more on being able to provide flow as you've got to supply fuel on a continuous basis rather than a peak impulse that fuel pressure provide.

It's true that if you've got a fuel pump that is way overspec for the fuel system, you'll be able to provide a "boost" effect for the fuel so you can get more fuel into the cylinder in a given time slice, however I believe if you put too much pressure through the injector, the injector will fail to atomise the fuel correctly and this will actually provide a detrimental effect on the combustion process. Anyway, the injectors have a very fine nozzle, something tells me that no matter how much pressure if you have behind it, you'll get a dimishing returns effect as you increase the rail pressure.

The last couple of points are things I've inferred, people who are enlightened with the ways of the flow dynamics and how injectors work, please englighten us =) I don't want to be spreading wrong information =)

Post by **smorison** » Wed Sep 08, 2004 12:02 pm

MADFTO wrote:
It's true that if you've got a fuel pump that is way overspec for the fuel system, you'll be able to provide a "boost" effect for the fuel so you can get more fuel into the cylinder in a given time slice, however I believe if you put too much pressure through the injector, the injector will fail to atomise the fuel correctly and this will actually provide a detrimental effect on the combustion process. Anyway, the injectors have a very fine nozzle, something tells me that no matter how much pressure if you have behind it, you'll get a dimishing returns effect as you increase the rail pressure.

The last couple of points are things I've inferred, people who are enlightened with the ways of the flow dynamics and how injectors work, please englighten us =) I don't want to be spreading wrong information =)

I'm not sure about the atomisation process when it comes to too much pressure through the fuel rails into the injectors however it makes sense... i've never tried it...

simpliest way to describe it is as a watering system with one of those trigger handles on it..

Ok imagine you have:

hose = Fuel Rail
Tap = FPR
Trigger handle = Injector

for this test you turn the tap fully open and adjust the spray so it comes out in an arc of atomised water.

You turn the tap to set the pressure in the hose, you turn it 25% pressure and press the trigger... the water dribbles out as one line of water... if this was fuel when you add O2 and a spark ... the fuel will burn very very slowly... and the mixture would be very lean (even if there is liquid fuel in the bottom it doesn't burn, only the vapour burns).

You turn the tap to 50% pressure and press the trigger... the water comes out in a spray however the drops are not atomised properly and when you add O2 and Spark the fuel ignites... this time it ignites properly and all the fuel burns however it burns slowly as it has to heat the large drops to turn them into vapour.

You turn t he tap to 75% and press the trigger... the water atomises properly... it burns properly ... etc etc....

the injectors in the FTO will be functioning somewhere around hte 70-80% mark when at what... as the injectors are designed to flow more there will be no real problems with delivery until we get close to 100%... i'd say 90-95% and we'd be wanting to change injectors...

paladin · Post by **paladin** » Thu Sep 23, 2004 8:06 pm

sounds very itneresting, but also sounds like it would run rich and ruff ? you still need the air imput to burn in combination so i dont think it would work very well/ reliably.

i once had a alfa 90 wich had hte wrong injectors in it (mix up at the injector cleaners) and it ran very rich/low revs it would stall

RichardH · Post by **RichardH** » Thu Sep 23, 2004 9:07 pm

GWIDO wrote:As extra air goes in the car starts to lean, Oxygen sensor detects this and changes injector rate to get correct mixture.

Can I add my tuppence worth to this. I'd understood that at wide open throttle the oxygen sensor don't do diddly. The engine ECU uses preset mappings for fuel delivery, using MAP sensor etc. to determine proper mixture.

Oxygen sensor is used at idle, and maybe light throttle. I'm fuzzy as to when the system goes from "closed-loop" (ie. feedback from O2 sensor) to "open-loop" (ie. preprogrammed behaviour).

As usual, feel free to correct/enlighten as required, anyone.

- Rich

MADFTO · Post by **MADFTO** » Fri Sep 24, 2004 12:12 am

Closed -> Open loop and vice versa is usually transitioned to at a certain throttle percentage I think.

That's generally what happens from my understanding.

Black_FTOGPX · Post by **Black_FTOGPX** » Mon Oct 04, 2004 11:42 am

HI Steve,

Have you had any luck getting the flow tests done yet?

Post by **smorison** » Tue Oct 12, 2004 8:15 am

Black_FTOGPX wrote:HI Steve,

Have you had any luck getting the flow tests done yet?

i didn't get hte results i've been stupidly busy at work and haven't visited Unique in a month at least (much to my girlfriends delight

)...

i have to get up there sometime this week and grab a heap of stuff from them as well as give them a nice set of cams for hte MIVECS....

i know on the GR the gain was approximately 10kW when the piggy back was retuned ... this also included riching up the car as it was dangerously lean...

Post by **smorison** » Mon Oct 18, 2004 8:58 pm

hey guys...
finally got the flow bench figures off rob's GR... mine will be going in soon (cams were sent in today)... as soon as we have this tested on a MIVEC we will be almost ready to sell them - we're just trying to locate a spare set so we can do them on an exchange basis (same day service) rather than taking a week.

Flow bench figures

MITSUBISHI FTO INLET MANIFOLD
FLOW FIGURES @ 28â€

wildfaye · Post by **wildfaye** » Sat Oct 23, 2004 1:31 pm

err...i m in spore...how do i do e exchange?
shipping costs will kill!

G_A_V · Post by **G_A_V** » Sat Oct 23, 2004 1:50 pm

hey steve what gains can we expect ?
the 10kw gain was from other things on top of the throttle body (ecu and tunning) what can we expect just from the new throttle body ? also any ideas as to cost yet ?

Post by **smorison** » Mon Oct 25, 2004 8:49 am

G_A_V wrote:hey steve what gains can we expect ?
the 10kw gain was from other things on top of the throttle body (ecu and tunning) what can we expect just from the new throttle body ? also any ideas as to cost yet ?

i haven't had a look at the GR dyno runs yet so i can't tell you...
there was a change made to timing so investing in a cheap piggy back like the perfect power one could be a good thing

p13nox · Post by **p13nox** » Thu Dec 02, 2004 1:15 am

I'm just about to attempt to bore out my throttle body. I have a spare mivec throttle body to try first. First question;
Is the mivec TB the same as the GX?

Second question, On the manifold side of the manifold there is a 'ledge' that protrudes, its only about 1mm thick and looks like it will be removed from a 3mm or 5mm bore. What happened with your TB?

Cheers

Post by **smorison** » Fri Dec 10, 2004 1:01 pm

p13nox wrote:I'm just about to attempt to bore out my throttle body. I have a spare mivec throttle body to try first. First question;
Is the mivec TB the same as the GX?

Second question, On the manifold side of the manifold there is a 'ledge' that protrudes, its only about 1mm thick and looks like it will be removed from a 3mm or 5mm bore. What happened with your TB?

Cheers

sorry can't give away the trade secrets

if you have a spare we'll happily do it on an exchange basis in the new year.

FTO AUSTRALIA

Unique: Throttle Bodies|Intake Plenum and Manifold

confusion

Re: confusion

Re: confusion