fuel pump Upgrade ?

[vxr2010]

Any one got any thoughts please , I've found a very good price on the mapping with FB Tuning , the car is a jdm sti ver 7 2001 bugeye , I have changed the plugs and panel filter it has original cat down pipe after that I have a straight through pipe and sports box , I'm only looking for a standard remap car is on 85k miles , do you have to upgrade fuel pump or is it advised ? It's a budget issue lol

[v8250]

Logically, if it's a standard remap you will not need a new fuel pump providing the fuel supply flow rate AND pressure required remain the same. If this changes you may need a larger capacity fuel pump. Talk to Richard at FBTuning...he knows is onions and will advise correctly.

[TEKNOPUG]

v8250 said:

Logically, if it's a standard remap you will not need a new fuel pump providing the fuel supply flow rate AND pressure required remain the same. If this changes you may need a larger capacity fuel pump. Talk to Richard at FBTuning...he knows is onions and will advise correctly.

As above. If the fuel supply is inadequate, the car can still be mapped but obviously performance will be reduced (more air/boost, requires more fuel). I would however, advise fitting one anyway. Fuel pumps rarely fail as in they stop working completely. What more often happens is that their efficiency reduces over time. They aren't that expensive and will be one less thing to worry about in the future. If money is tight, maybe consider a second-hand one from one of the breakers and take it with you to the mappers, just in case.

[vxr2010]

Hi cheers for replies , I'm assuming fuel pressure can be measured when mapping ?

[AntiLagGC8]

A lot of the engine builders/mappers suggest changing the pump if its over 5 years old anyway.

The Walbro 255 fuel pump is a common one.

I've got one of these and think the pricing is very reasonable; http://rogerclarkmotorsport.co.uk/store/product/24...

I'd recommend you chat with the person doing your mapping about what they'd suggest.

[vxr2010]

One warlbro ordered , but do I fit in the Foz sti with 125,000 or the Impreza with 87,000 miles , the last chap who mapped the car said I did not need one, so its more of an age or mileage covered issue, both basic mods as in cat back and a basic remap , expensive sorting two Scoobys out

[AntiLagGC8]

I would replace the pump on the car having the remap first.

[vxr2010]

Unfortunately Foz already done and Impreza due , and now it's getting to buying Xmas present time , oh a warlbro from the Mrs I hope

[vxr2010]

Good old eBay , I've bought a fuel pressure guage it was only 12£!, I think its supposed to be around three bar , I will see how the pressure is and therefore how worn the pump is

[Vixpy1]

replace the pump in the Sti as a matter of coarse before the remap, the RCM one's are very good, don't buy a cheap one off ebay.

[vxr2010]

I bought a walbro 255 on eBay , both are Sti s , at least I can pressure check them , lowest pressure gets the new pump now and if other car is too low then a new one on that too if it needs doing , the boost will be higher on the sti Impreza as a larger turbo , it's surprising how different the 2 and 2.5 litre sti s drive

[Vixpy1]

The foz has a bigger blower , and you won't see a pressure drop until you put more demand on the pump with the remap

[vxr2010]

Foz has much smaller turbo it's only a vf39 which is why there is less lag but lower boost its Max's around 1.25 to 1.3 and that's after mapping , the Impreza is peak 1.4 to 1.5 in higher gears and it's not been mapped yet , Subaru went bigger cc smaller turbos

[Vixpy1]

Foz should have a vf41 on it , and it spools better and runs less boost because it's a 2.5 engine .

[vxr2010]

Yup my error the vf41 I could not remember which one , power is more instant on Foz it just runs out quicker , it was as quick as or possibly quicker than my friends 2.5 spec d that was remapped so no slouch

[vxr2010]

Any one got any idea ? I've put the guage on it showed about 10 psi on idle on both cars is that normal , I assume pump works harder when it needs to , no cel or any thing else showing up , my thoughts are why change what's working plus the cost of doing two of them

[vxr2010]

I think I connected it wrong seems I need to stop return fuel pressure to find out what it's actually doing , a job for tomorrow

[vxr2010]

Well finally all done , both have around 43 psi which goes up when fuel rail regulator is disconnected , so that is peace of mind , plus I have a walbro that should do either one if I need to , I'm going with don't touch it if it's not broken fuel pump idea , one has highish mileage around 130,000 miles , the other is age it's a 2001 car but neither has currently effected the fuel pump working , on the plus side I needed to change two fuel lines that were not that obvious with out closer looking , guage was about 12 £ to my door via eBay , and you need ptfe tape to seal joints on the guage , and connect it between the fuel filter out and the in line to the fuel supply which is the top one of the three , but if nothing else check your fuel lines