Do I need to upgrade my fuel pump
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Hi, I'm having a de-cat down pipe fitted to my 06 wrx this weekend and I'm getting it remapped by dynamix. I keep seeing people recommending upgrading to welbro fuel pump etc. Should I get one? essential or opinion?
Thanks
Thanks
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From: The hell where youth and laughter go
Ain't broke don't fix:
Quick blast on the rollers with a fuel pressure guage connected (or taped to windscreen if done on the road - as I do
) will prove its up to the job.
Would consider it if upgrading the turbo to a larger unit, but before that I wouldn't bother.
Quick blast on the rollers with a fuel pressure guage connected (or taped to windscreen if done on the road - as I do
) will prove its up to the job.Would consider it if upgrading the turbo to a larger unit, but before that I wouldn't bother.
Last edited by ALi-B; Jan 26, 2010 at 03:17 PM.
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This isn't a conclusive test, to give a fuel pump a clean bill of health...
Consider the flow volume, as well as it's ability to make the pressure dictated by the regulator

I recently tested a mildly modified STi3 on the dyno that was running at 12.5:1 at full boost on the standard ecu. The original pump was showing 3.0Bar of fuel pressure with no vacuum.- Having changed the pump for a Walbro 255l/h, the pressure remained the same, but the fuelling richened up to 11.3:1 through the midrange, tapering to 10.8:1 at the top end
Had the fuel pump been deemed OK by a simple pressure test, the engine would have blown itself to pieces in fairly short order

For the sake of £70 odd, a Walbro255 is a good investment for any standard or mildly modded Impreza IMO
Last edited by FB Tuning; Jan 26, 2010 at 07:37 PM.
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From: The hell where youth and laughter go
I recently tested a mildly modified STi3 on the dyno that was running at 12.5:1 at full boost on the standard ecu. The original pump was showing 3.0Bar of fuel pressure with no vacuum.- Having changed the pump for a Walbro 255l/h, the pressure remained the same, but the fuelling richened up to 11.3:1 through the midrange, tapering to 10.8:1 at the top end
Flow and pressure are proportional. To change flow without changing pressure another variable in addition to the pump must have been altered. Assuming there is more flow and the enrichment is not due to something else that was done other than the pump...
Not going to go into page long specifics in fear of derailing the topic - Maybe something better left for another thread. So just take it as my opinion.
Last edited by ALi-B; Jan 27, 2010 at 12:28 AM.
Why pay for the testing of yours when you could put the money towards the upgraded fuel pump fit and forget.Its the best option its a false economy paying to have it tested.I was told by my mapper to change mine before getting it mapped whatever the mods are, and he is one of the best outhere.You will almost definately go for more power and it will be ready to provide .
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