Walbro fuel pump overpowering the standard MY99/00 fuel pressure regulator
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Bob originally mentioned this, and on checking my fuel pressure it was about 3 bar at idle, atmospheric, throttle blipped etc. Fitting a new regulator has given the expected response, although perhaps not quite the setting minus idle vac it is not far off.
The closed loop correction varied over time and sometimes it started abruptly. Leaning out the map sorted it for a while and then it happened again, as though fuel pressure was rising over time.
Any others? Should we all be doing a regulator with the fuel pump because of this issue?
The closed loop correction varied over time and sometimes it started abruptly. Leaning out the map sorted it for a while and then it happened again, as though fuel pressure was rising over time.
Any others? Should we all be doing a regulator with the fuel pump because of this issue?
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The pump can make a huge difference - especially if you have upped your boost.
On track I had a real problem controlling the egts at the top end - and no amount of mapping would correct it - simply it was the fuel pump not providing enough fuel. With the Walbro - problem solved - plenty of headroom in fuel flow and egts were fine.
So IMHO a HUGE difference for one low cost change.
Rannoch
On track I had a real problem controlling the egts at the top end - and no amount of mapping would correct it - simply it was the fuel pump not providing enough fuel. With the Walbro - problem solved - plenty of headroom in fuel flow and egts were fine.
So IMHO a HUGE difference for one low cost change.
Rannoch
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Indeed agree massive benefits from the pump when you tune UK cars much beyond the high 200s and it seems STis at all. Just wondering about the idle fuel pressure thing. Needed to change the regulator anyway because it was in the way of the turbo. I suppose it only became an issue after the 550s.
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It is overpowering my regulator on the 22B like you say. It is having the new Mark Aigin supplied reg fitted Thursday then another re-map
The figure with the "hose off" was too high i.e its not closing properly (as I understand it?)
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#8
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The std fuel reg has about a 2.0mm orifice to flow all the fuel thro' so its no suprise it gets backed up when the Walbro pump is installed, also means it ends up very non linear and variable. RCM are now offering the SX reg plus fitting kit as a complete package and will also install to boot, its a pig of a job on the Classic cars but the new age have the reg at the front of the fuel rail. Be aware that the rail adaptor that fits the classics will not fit a new age.
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Andy, no didn't monitor the fuel pressure, didn't have the means to do so, all that I can remember were that my IDC's dropped after fitting and a remap.
Can't remember much about the car at all these days, it's been in pieces since September
Can't remember much about the car at all these days, it's been in pieces since September
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Is it recommended to fit an uprated fuel pump/regulator prior to a remap. Could the car run too rich or does the duty cycle of the injectors simply lower to supply less fuel? Going to be fitting Link set up in the not too distant future.
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John if your still using the standard fpr I guess you havn't converted the fuel rails into a parallel configuration. So you don't believe thats necessary? (I'm only asking, not sayoing your wrong)
Duncan
Duncan
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Here we go again ![Big Grin](https://www.scoobynet.com/images/smilies/biggrin.gif)
Question: Are any of the mappers / tuners of STI-7's changing the regulators....if so why ? if not why ?
Once again, why would Prodrive supply uprated pumps with the new PPP but not regulators if neccessary ?
Seems like a whole new tin of worms about to be unleashed but I need to know as I am having a remapp and new fuel pump stuck on me old JDM STI7.
Cheers,
Ray
PS: What is the worst that can happen if the regulator is not replaced.....is it the same as not upgrading the fuel pump...ie: fuel starvation and bang ! ??
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Question: Are any of the mappers / tuners of STI-7's changing the regulators....if so why ? if not why ?
Once again, why would Prodrive supply uprated pumps with the new PPP but not regulators if neccessary ?
Seems like a whole new tin of worms about to be unleashed but I need to know as I am having a remapp and new fuel pump stuck on me old JDM STI7.
Cheers,
Ray
PS: What is the worst that can happen if the regulator is not replaced.....is it the same as not upgrading the fuel pump...ie: fuel starvation and bang ! ??
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Wether to change a reg or not in addition to the pump is really down to what level you are going to upgrade, the further you go the more specific you need to be with fueling, as a guide, if installing uprated injectors then the reg "should" be changed, if sticking with std's then probably ok as is. This is because granularity ids affected when injectors are changed and a small pressure variation can cuase a much bigger fueling change as a result.
bob
bob
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Bob, im going to be arranging for a Link setup i bought to mapped by yourself (used to be Toby Meech's). Is it ok to use NGK PFR-7B's when doing so? Also going to fit an uprated fuel pump to go with the Link, so i would be ok leaving the standard FPR?
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And an STi 7/8?
Bob (or anyone else![Wink](https://www.scoobynet.com/images/smilies/wink.gif)
), you say when fitting bigger IJ's the FPR becomes more important? Bigger than what? I ask because the STi 7/8 has 565cc's (right?) so would they constitute "bigger" than say what I assume is being called "standard" (440's?) so basically, on a 7/8, do you think an uprated FPR is required if you uprate the pump?
Ta,
Matt
Bob (or anyone else
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Ta,
Matt
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