Question on fueling limit with a bigger Walbro 255 pump

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PlasticMonster
Posts: 22
Joined: Sun Feb 13, 2005 10:37 am

Question on fueling limit with a bigger Walbro 255 pump

Post by PlasticMonster »

Hi, The previous owner fitted a walbro 255 intank fuel pump, but I am still running standard injectors.

Will this allow them to go slightly further than standard (my understanding is that that is about 330 bhp) or it it just a prep for bigger injectors and aftermarket ecu later?

During my new rebuild I will also be fitting piper fast road cams (basically 264's) again will the additional lift (or duration) allow more fuel in and thus extend the bhp level of the injectors or is this not related.

Hope you can understand what im trying to get at. basically the rebuild has left me more than skint and I want to know how far I can push my setup with whats in place already.

Before the build I had 265 bhp @ 300ftlbs on standard boost, I can afford a boost controller (the hybrid Turbo Technics CT26 I have is apparently good for 380 bhp) but wanted to keep my expectations realistic when its fitted and mapped. Just cant do bigger injectors or fuel rail right now.
PlasticMonster
Posts: 22
Joined: Sun Feb 13, 2005 10:37 am

Re: Question on fueling limit with a bigger Walbro 255 pump

Post by PlasticMonster »

Please anyone.. Will a bigger fuel pump extend the operational capacity of a standard rev 2 injector.. Ive run searches but cant get a def answer.
Martin F
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Re: Question on fueling limit with a bigger Walbro 255 pump

Post by Martin F »

no, they will still have there running limits, an uprated pump is designed to run enough flow for bigger injectors where an old factory pump wouldn't be able to manage or just to replace an older worn out pump...

the rev2 injectors are 440cc and should be ran at the set/recommended pressures to perform at there best.

at least now though the pump is in place if you ever decide to modify the car where it would need bigger injectors :wink:
PlasticMonster
Posts: 22
Joined: Sun Feb 13, 2005 10:37 am

Re: Question on fueling limit with a bigger Walbro 255 pump

Post by PlasticMonster »

Brilliant thankyou, am I also about right on the upper limit of them at 330 or are they gonna run out sooner than that. I think they are the next power barrier Ill hit.

Really appreciate the advice.
Martin F
IMOC Moderator
Posts: 14822
Joined: Fri Aug 04, 2006 1:19 pm
Location: The Couch !

Re: Question on fueling limit with a bigger Walbro 255 pump

Post by Martin F »

PlasticMonster wrote:Brilliant thankyou, am I also about right on the upper limit of them at 330 or are they gonna run out sooner than that. I think they are the next power barrier Ill hit.

Really appreciate the advice.


330 bhp is a rough limit for rev3 injectors which are 540cc, think the rev2 injectors are around 280 bhp :-k
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