Are Fuel Regs Safe

[EVL032]

just wondering is my malpassi rising rate fuel regulator hurting my injectors?

some ppl say yes some say no whats your thaughts

this is my way that i can be bothered changed changing the injectors on my rb20det and will this support 200+rwkw cause i am up at 183rwkw and everything seems fine just want a little more boost and a little more fuel???

[NA_R33]

in my opinion they are a great alternative but this is gonna spark some great debate!!

[Sydneykid]

just wondering is my malpassi rising rate fuel regulator hurting my injectors?

some ppl say yes some say no whats your thaughts

this is my way that i can be bothered changed changing the injectors on my rb20det and will this support 200+rwkw cause i am up at 183rwkw and everything seems fine just want a little more boost and a little more fuel???

<{POST_SNAPBACK}>

Rising rate fuel pressure regulators are tricky to tune for at times, I prefer a linear rate adjustable fuel pressure regulator. Rising rate FPR's are usefull for the older ECU's that didn't have rich and retard mapping.

Nothing wrong with increasing the fuel pressure above standard, to sneak a little more flow out of the injectors. As long as the fuel pump can deliver the extra pressure and still maintain the flow rate. That's the difficult part, an example. You might increase the fuel pressure by 10% and achieve a 4% increase in fuel flow from the injectors. But because of the extra resistance (pressure) the fuel pump might actually flow 6% less fuel. So you can actually go backwards if the fuel pump is not up to it.

The other issue is the ability of the standard rubber hoses and hose clamps to hold the increased pressure. Split hoses and leaking clamps are not good for fuel and a hot engine bay.

cheers

[pnblight]

Sydneykids is spot on and i would just be carefull as you adjust regulator, chances are you need a new pump as they offen drop off dramatically as pressure increases (not designed to run much higher pressure but they will go a bit)

I have managed good results out of my std r33 gtr fuel system but only because i retain std fuel pressure and when the other way by putting big injectors (namely 530rwhp out of std fuel system and have done so on a r34 aswell)but for safety sake they will be upgraded in time.

So if your only looking for a few exact psi fuel pressure it shouldn't be a problem if your fuel pump still has a bit more in it. But if your looking for quiet a bit i would bit looking at bigger injectors and ecu to control them correctly.

[rob82]

If you want more fuel pressure make sure you put the rising rate regualtor on after the standard item as they retain pressure up to 40psi better than most aftermarket items as it has a steel diaphram.

[EVL032]

yeh i have a 500hp denso fuel pump and yes the adjustable fuel reg. is installed correctly as i got an adaptor to get rid of the standard item

so it is alright then by the sounds of it???

[Beer Baron]

my advice is don't trust the malpassi regulator i know of a number of people who have had trouble with them. particularly the gauges they come with.

[4door_Sleeper]

my advice is don't trust the malpassi regulator i know of a number of people who have had trouble with them. particularly the gauges they come with.

<{POST_SNAPBACK}>

I have also seen the malpassi used on a number of big budget drag cars - so they cant be all bad.

[dangerous_daveo]

I have also seen the malpassi used on a number of big budget drag cars - so they cant be all bad.

<{POST_SNAPBACK}>

Right on. If you keep them away from heat they really arent too bad. That said I have a bracket coming off my plenum for my reg, and its fine, get stuck in traffic, open the bonnet, its holding pressure perfect.