elim0

hey just wondering how long will the stock fuel pump suffice before is it necessary to change the stock fuel pump (evo8) to a upgrade (ie. walboro 255l ) ? after exhaust? after intake ? tune? cams?

and what will happen if you mod the car and dont change it ?

i have heard you just 'need one' when modding the car and friend was asking but i couldnt give him a proper answer except that lol

TIA !

Ramen_Noodle

iTrader: (3)

It's a cheap part, it's better to be safe than sorry, never skimp on fuel system components. If you don't change it, you'll probably run lean, blow your motor, etc.

foxbat

8's are already 10 years old get a walbro 255

elim0

he's had the car for over 6 months now which he purchased with intake/exhaust/cams/ tune etc and it seems to be running fine, i was looking at the ad of his car and it didnt mention fuel pump upgrade and was curious, when i asked him he said he didnt know and would he need one? he would surely have to have it already right lol..

ReaperX

iTrader: (5)

Pull out the pump and take a peek to see. Fuel pump is cheap insurance.

M8NSTER

Cam/Tune I would assume there is an after market pump in there. 8 pumps are like 185lph (you would run really lean), 9's are like 215lph.

You can hear a whine from a Walbro, just fyi.

elim0

okay so we spoke to the previous owner and he said he does not remember putting a fuel pump in, spoke to his tuner (a reputable tuner i also know) and he says that, that is one of the first things they do before tuning and doesnt believe the power figures could be reached on a stock pump without being super lean which would have be spotted in the rune/dyno runs.

so tomorrow we are going to take it apart and have a look ourselves.

Another issue is, if its upgraded its fine and done. if its still stock, that means the car was tuned with this and would run fine? or would it be worth throwing the walboro 255 in, as yes i know its cheap, but some tuners have said it'll be fine with tune, while others say a re tune is needed (which is a lot of $$) ???? what do you guys think ?

foxbat

There a slight chance that tune might require some adjustment, but not a full re tune! Any decent tuners would take it for a couple of runs & do AFR data logging & confirm whether it require adjustments or not.

elim0

anyone else know if it'll be fine to install a walbro 255lph or will it have to be re tuned?

anyone know if the current one will be fine as its been tuned for it ? even though it runs full bolt ons / cams / evo9 20g turbo @21psi ..

3K

iTrader: (9)

If it was tuned w/stock pump, throwing a 255 in will make it run richer without a tune. So you'll pobably end up having to lean it out alittle.

elim0

a few people say this is the case, while others have said since the fuel pressure regulator and injectors are staying the same the car will be pumping the same amount of fuel as normal ? as in it will have the ability if anything fails to pump more fuel as a safety margin but otherwise wont? very mixed answers on forums and from asking people .....

also do you think it will be safe to run the stock pump and leave it as it is since its been tuned like that? im just worried cos of cams and increased boost

3K

iTrader: (9)

It will run richer. not in closed loop though because the ecu will compensate for that. only in open loop, wot that it'll run richer. without a WB02 you probably wouldn't even know its running richer. You may have to slightly tweak your tune or you might not even have to make any changes to your current tune.

But the pump swap is so easy and cheap to do, you should just do it anyway.

foxbat

AFR may or may not get rich, in either case, it's perfectly safe to install a new pump!

elim0

hopefully the install is simple and straight forward and the car doesnt change in driveability. any negatives of running a little rich? bad gas milage? loss of power ? bad for motor?

friends just short on cash and if a retune is in order got quoted $400, which is a bit steep i think, and if thats the case might as well save up for a few more things and get the thing properly fully tuned

sparky

iTrader: (1)

Hey, don't rub it in Foxster.