Walbro fuel pump overpowering the standard MY99/00 fuel pressure regulator
#33
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Pete/Tim W
Did you monitor the fuel pressure under different conditions ? Or do you mean the engine 'ran' fine ?
Andy
[Edited by Andy.F - 3/4/2003 8:02:20 PM]
Did you monitor the fuel pressure under different conditions ? Or do you mean the engine 'ran' fine ?
Andy
[Edited by Andy.F - 3/4/2003 8:02:20 PM]
#34
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I was shocked at how weedy looking the standard reg is. Let me be clear this is not an issue with the fuel pump, just wondering if it "should" be fitted with a regulator? Everyone is recommending a fuel pump for any decent tuning, should be all be doing the regulator as well as a matter of course (on the models affected)? If the 22B is doing it sounds like a Phase I reg if it is the same on the 22B as the rest... Phase II is doing it on the 99/00. What about the new age/STi? Particularly on the STi 7 with the PPP/Ecutek/other ECU s(especially since there is a well documented issue with the STi 7).
[Edited by john banks - 3/4/2003 8:32:01 PM]
[Edited by john banks - 3/4/2003 8:32:01 PM]
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John,
did you bottom this out. Have had horrendous overfueling problems recently - and very non-linear - walbro with standard reg - and it seems to be gettings worse all the time!
My sense is that it is the reg - generally running richer than it is mapped - also getting high fuel misfires and resulting BK flamer whoppers on WOT!
Rannoch
did you bottom this out. Have had horrendous overfueling problems recently - and very non-linear - walbro with standard reg - and it seems to be gettings worse all the time!
My sense is that it is the reg - generally running richer than it is mapped - also getting high fuel misfires and resulting BK flamer whoppers on WOT!
Rannoch
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I changed the regulator to a static rate FSE one and the starting problem resolved completely - before it used to fire up far too abruptly on the 550s - idle fuel pressure when measured was silly high - it wasn't really dropping on vac. I didn't have a problem with full load mixtures, but things seemed to go off with time on the standard reg from the point of view of idle mixtures and starting.
#37
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So - after reading all that i'm still a little confused...
the story so far: MY99, decat, a JB tek2.5, dawes and ITG Filter.
I've just got the walbro fuel pump kit and was about to fit it in preparation for a revised turbo (probably front entry TD05 from Mark) with a view to just over 300 bhp. i wasn't planning to revise injectors or TMIC.
1. do i need a new fuel pressure regulator before i fit the pump?
2. will i need one before the turbo and remap?
Many Thanks...
Jon
the story so far: MY99, decat, a JB tek2.5, dawes and ITG Filter.
I've just got the walbro fuel pump kit and was about to fit it in preparation for a revised turbo (probably front entry TD05 from Mark) with a view to just over 300 bhp. i wasn't planning to revise injectors or TMIC.
1. do i need a new fuel pressure regulator before i fit the pump?
2. will i need one before the turbo and remap?
Many Thanks...
Jon
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Jon, until I personally experienced the problem (which for some reason was far worse after 550cc injectors) I would have said just use the pump. However the regulator would have two advantages - 1 the consistency, and 2 it would give us some extra fuel which you TD05 may well need depending on boost.
#39
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I've had 2 OEM regs give up the ghost when using the Walboro pump with 550's. With one of them the mixture was so varied at idle we could not add/remove fuel quick enough to keep it running. Also had problems with an FSE adjustable too.
#41
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The pump just has too much flow for the std reg, its only got a 2.0mm orifice to flow all that fuel thro' so its not suprising, if you fit an uprated pump you should change the reg as well otherwise you are not getting the full benefit of the pump and almost certainly will suffer variable off boost fueling, think I posted this up sometime last year as I had horrendous problems with my own car in this respect.
#44
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I think Mark at Lateral performance sells a nice one with a pressure guage too. (saw it on Fuzz's thread)
http://www.scoobynet.co.uk/bbs/thread.asp?ThreadID=184332&Page=3
I'm looking at getting one of these myself.
http://www.scoobynet.co.uk/bbs/thread.asp?ThreadID=184332&Page=3
I'm looking at getting one of these myself.
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Its worth noting the size of the orrifice in after market regs as well they arent that big on the 1000hp rated fpr's so I dont think its down to the hole..
possibly more down to the diaphram in increased boost pressure..
David
possibly more down to the diaphram in increased boost pressure..
David
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