Tuning Fuel Pressure Regulator 1242 8v Feed Only

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Tuning Fuel Pressure Regulator 1242 8v Feed Only

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hey all,

as you know im turbo converting the engine 1242 8v MPI FIRE in a punto mk2...was just wondering am i needing to use one of them rising rate aftermarket adjustable fuel presure regulators (FSE)?? to raise the fuel pressure at the injectors?

the engine only has a fuel feed and no return to the tank i dont know wether this will effect it or not?

i think the standard regulators are built into the pump on the punto so not able to remove the standard one iv been told but i can still add this on the feed near the injectors if needed

cheers
brin :)
 
Mk2s (MPI's in Cinq/Sei speek) deliver at 3 bar which is the right pressure. The only question is, will the stock pump deliver at the correct volume?

I doubt it. Ask a fuel pump specialist. Work out how much fuel you'll need to supply an engine making your target horsepower and ask them.

But the whole idea of using a half-arsed peice of bolt on tat on an MPI system is beyong me.

It's barking mad.
 
Mk2s (MPI's in Cinq/Sei speek) deliver at 3 bar which is the right pressure. The only question is, will the stock pump deliver at the correct volume?

I doubt it. Ask a fuel pump specialist. Work out how much fuel you'll need to supply an engine making your target horsepower and ask them.

But the whole idea of using a half-arsed peice of bolt on tat on an MPI system is beyong me.

It's barking mad.

im just needing to increase fuel pressure tbh mate dont care how lol...i know the SPI turbo cinqs had one fitted from van akken

only other option will be to change the punto pump for say a GT one and plumb me own return line and change the fuel rail..which is a big job the FSE just seemed a lot easier but if it dont do sh*t then i cant see the point tbh
 
Why do you think you need to increase fuel pressure?

Engage brain, man.................

A given engine will need a particular quantity of fuel to produce a particular bhp figure.

It doesn't care about the pressure.

BUT the injectors are calibrated to produce a particular flow at a particular pressure (on modern injectors 3bar). Changes to this pressure will increase (or decrease) flow, but generally in a non linear and (above 4 bar or so) erratic fashion.

You need a pump to produce the required flow, not the pressure.

There are a huge number of pumps available. Some will expect a return, some not. Most will simply fit into the existing carrier ion your Punto.
 
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Why do you think you need to increase fuel pressure?

Engage brain, man.................

A given engine will need a particular quantity of fuel to produce a particular bhp figure.

It doesn't care about the pressure.

BUT the injectors are calibrated to produce a particular flow at a particular pressure (on modern injectors 3bar). Changes to this pressure will increase (or decrease) flow, but generally in a non linear and (above 4 bar or so) erratic fashion.

You need a pump to produce the required flow, not the pressure.

There are a huge number of pumps available. Some will expect a return, some not. Most will simply fit into the existing carrier ion your Punto.

Cheers bud, sorry I was just going by what the SPI cinq have done I noticed that van akken used one these fuel pressure regulators is all mate wondered if I needed one as it seems to work on the SPI and wasn't sure about it....thanks for clearing it up :)
 
Regulators with a return are superior for a number of reasons unless the regulator is positioned after the injectors. This will save me some typing:

http://www.centuryperformance.com/f...tanding-fuel-pressure-and-volume-spg-140.html

However you would need to remove whatever regulation is currently fitted and also upgrade the pump to make it worth while. Of course this is only worth doing if your current fuel system can't handle the requirements of your turbo set up. Also you need a regulator that will understand boost refference I have have no idea if the standard item on a Punto can do this.

How are you planning on adding extra fuel with the MF2 anyway? Are you going MPI/MPI?

I have SPI/MPI but going MPI/SPI would be rather insane and not worth the effort IMO.

Your cheapest option would be upgrading the fuel system, use bigger injectors and fool the map with a comprehensive piggy back to give sensible fueling off boost. Otherwise go the hole hogg and just fit a stand alone and get somone knowledgable to set it up.

It's a lot cheaper and more fun than a minced engine.
 
go the hole hogg and just fit a stand alone and get somone knowledgable to set it up.

It's a lot cheaper and more fun than a minced engine.

Yep. Pretty much the point many of us have been making all along.

If you start MPI, then aftermarket ECU is really the only sane way to go. Cheaper, too, and if you learn something useful, it'll be useful in this century!

Think of the joy of not having to wonder if you're about to loose a piston due to underfuelling! ;)
 
Of course but bear this in mind, if the current injectors aren't up to the job at 100% duty cycle 3bar you'll still have to either increase the fuel pressure, enlarge the injectors (and pump) or finally add a new bypass or restrictive regulator.
So as many Fingers stated earlier you need to calculate the maximum output of your current fuel system and go from there. Personally I'd upgrade with a bypass regulator and a better fuel pump, then rather than learn all about setting up a piggy back/standalone get a pro to do it and hopefully let you watch and learn.

Of course there is the option of reprogramming the standard ECU but that is beyond most and takes a fair amount of dedication.
 
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the VA tubs use them coz the standard injector runs a low pressure (1.0-1.2bar) and you want a higher pressure (2.5-3.0bar) on the 'extra' injector..

From what you wrote your not understanding how these work.. they control pressure upstream of the fpr not after it so sticking it in before the fuel rail would be wrong in every way. It has to go after the fuel rail to control pressure in the rail. As i understand your rail is a non-return type, in which case i'm not sure how you can plumb one of these in properly tbh? i've seen it done but how it was fitted exactly i don't know.
 
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the VA tubs use them coz the standard injector runs a low pressure (1.0-1.2bar) and you want a higher pressure (2.5-3.0bar) on the 'extra' injector..

From what you wrote your not understanding how these work.. they control pressure upstream of the fpr not after it so sticking it in before the fuel rail would be wrong in every way. It has to go after the fuel rail to control pressure in the rail. As i understand your rail is a non-return type, in which case i'm not sure how you can plumb one of these in properly tbh? i've seen it done but how it was fitted exactly i don't know.

Yh yh I got you now mate...I thought it justbolted between the feed as a sort of restrictor to increase pressure but I now see it goes in the return after the injectors mate...il have a play around d with the fuel pump if it's needed :)
 
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