Simplest mod ever

I imagine the terrible fuel economy will have adverse effects throughout the car in some way. If it's only running rich during idle then it doesn't seem so bad, unless the pressure causes something to fail/blow or the excess fuel in the system starts to work against you. How? I don't know, I have no idea. But dumping fuel with no regulation sounds like a terrible thing for a daily.
 
Might rethink (where the pressure goes) and read more, but I think I've shown myself the value of getting another FPR that removes the flat spot. I'm on the throttle so much maybe the pressure doesn't matter lol.
 
Definitely read up on it more, but if you can't see a fault and think it suits your application, by all means keep doing it. What the *fudge* do I know lol
 
Ok, I think I've got it. At WOT FPR is maxing out, and since injector opening time is controlled, max pressure delivers the right quantity of fuel for that throttle position. So, the system can handle the pressure and nothing will burst, does that seem reasonable?
Now, at low rpm the system is starved by FPR, less volume is delivered than throttle position and ECU would call for, bringing on economy and large amounts of lag. Upping the pressure provides a greater volume of fuel but maybe only slightly more than what is required, but I've done a couple of "breathing" mods meaning I have probably coped with the extra fuel. Does that seem plausible?

What are the problems with running mildly rich a small % of time, apart from on the hip pocket?

I'm looking to see if my ECU can be reflashed soon, so there might be an even better outcome if I can do that.
 
At low load (typically cruising or idle) the engine is not starved of fuel, its operating in closed loop mode, which means its regulating the fuel using the O2 sensor as feedback. The injector duty cycle is like less than 20%. Which means its not even near capacity.

The pressure regulator balances the pressure based on flow, its like your thumb at the end of a hose. When you cover it up, you get lots of pressure, but not much water, but the more water you let out, the more the pressure drops. The regulator is like opening the tap more, as you let more water out, to keep the pressure the same, but with more flow.
 
Also, look at any evo build or any car thats making any power. None of them have just disconnected the FPR.

Why? Because its not good to do lol.
 
All of that is fair enough, but I'm sure EVOs don't have an FPR designed for economy, plus their pressure needs to be related to boost. Also, closed loop means I shouldn't run rich since the duty cycle will be reduced accordingly, but also I'm breathing better, which helps compensate richness.

As I've said, maybe all I've done is shown the value of an alternative FPR (which must react better to vac changes and/or run higher pressure at each throttle pos apart from WOT). The FPR is holding pressure in the fuel rail up to a maximum, so less is returning to the tank. The stockie runs somewhere in the vicinity of 38-50 psi (idle to WOT) so I'm running WOT pressure always. Lag problem gone and possibly no others created. Will wait, read, watch and decide.

I guess I was really searching for a solution to that dreaded lag when I don't want to kick back (or sometimes it won't, manuals probably behave differently) and increase revs that way. It certainly has accomplished that. I can distinctly feel these things when driving: closed to open loop change, lag at low rpm, powerband. I'm not getting confused with these things so I'm glad I've found a possible cause.
 
I was also looking into getting rid of flat spots. The only safe way to do that would be getting a aftermarket fpr or getting your ecu reflashed and tuned. I had my ecu reflashed and instantly took the flst spot out. Part of the reason you get a flat spot is due to the air fuel map of your ecu. Factory tuned ecu are tuned for economy so anything under 3k is usually running slightly leamer to save fuel which was manufacturers priority when these cars roll out of the factory. So my suggestion would be to upgrade your fpr or get a reflash. The reflash really opens up your power band.
 
Willy.T said:
I was also looking into getting rid of flat spots. The only safe way to do that would be getting a aftermarket fpr or getting your ecu reflashed and tuned. I had my ecu reflashed and instantly took the flst spot out. Part of the reason you get a flat spot is due to the air fuel map of your ecu. Factory tuned ecu are tuned for economy so anything under 3k is usually running slightly leamer to save fuel which was manufacturers priority when these cars roll out of the factory. So my suggestion would be to upgrade your fpr or get a reflash. The reflash really opens up your power band.
Click to expand...

How much did your reflash cost?
 
Well lets just say it was worth it. I had llt reflashed mine. Fuel and ignition mapping cost me 300. Not sure the cc range ecus could be reflashed though.
 
Willy.T said:
I was also looking into getting rid of flat spots. The only safe way to do that would be getting a aftermarket fpr or getting your ecu reflashed and tuned. I had my ecu reflashed and instantly took the flst spot out. Part of the reason you get a flat spot is due to the air fuel map of your ecu. Factory tuned ecu are tuned for economy so anything under 3k is usually running slightly leamer to save fuel which was manufacturers priority when these cars roll out of the factory. So my suggestion would be to upgrade your fpr or get a reflash. The reflash really opens up your power band.
Click to expand...
So I'm artificially enriching the AFR but in an uncontrolled way. I'm heading to Steve Knight Racing in the coming days to see if he can read my ECU. A reflash is possibly the last easy mod for me and makes another FPR unnecessary.
 
That should help, as his core business or even interest is getting power from turbo variants....
 
He said he'd have a look. He has a bench top loom so if he can read my ECU he knows what to change that will work. He has a dyno so might do before and after runs or tune with it.
 
So today I had a relaxing day spent it at the new place slowly unpacking things and just generally chillin', then my fiance got home from her shopping (she was out with a friend). We then went out to office works and bought a study desk for her and ikea for a display case for myself yay! So after having burritos we went and assembled all the furnitures. Now after finishing the study desk and starting on the display cabinet i decided to have a small break and watch some deep space nine. So while watching i got on auslancer and read this.



My night has now ended in much disappoint... So much disappoint...

#putthatvachosebackonffs #realmodsfromnowongawdplease #blownengine #washedcylinderwalls #highfuelconsumption #bandaidfix #placeboeffect #makesbabyjesuscry
 
i still find it funny the only responses as to why not to do it are:
1.its a bad idea
2.Evos dont do it so you shouldnt
3.mitsubishi is so wonderful they tuned this car to be perfect so dont muck it up.
4.(implied) bad fuel economy

all with the end result of it will kill your car but not as to why or how.
 
Read the hash tags about. Mainly #blownengine #washedcylinderwalls

You will wash the oil off the bores if there is to much fuel. That inturn can cause glazing of the bore. That in turn will pretty much its farked and you need a rebuild. You know its bad when your oil smells like fuel.

This is the how. Might take a while being a smaller injector but still.
 
mycarlisa said:
i still find it funny the only responses as to why not to do it are:
1.its a bad idea
2.Evos dont do it so you shouldnt
3.mitsubishi is so wonderful they tuned this car to be perfect so dont muck it up.
4.(implied) bad fuel economy

all with the end result of it will kill your car but not as to why or how.
Click to expand...

Its not everyone's job here to educate on why it's a bad idea, maybe go google fuel pressure regulators and how they work and then you will hopefully have a better understanding of why it's called a fuel pressure regulator. There are many ways it could impact your car and no one here is a fortune teller so no one can give you exactly what it's going to make fail first. But by all means if you think you know better than the engineers and designers over the years go ahead and give it the ol' try and be that innovator to throw caution to the wind and prove generations of engineers wrong. Or fail miserably, worst case blow an engine or some other kind of bad thing.

Oh and here a simple google link as a starting point

https://www.google.com/search?=client=m ... tor+in+efi

#kidsthesedays
 
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