Fuel Pump???

[MichaelGT]

Hi there,
The fuel pump on my polo gt has completely split but i'm just looking for a new one and not too sure if the standard pump is what i need, if a g40 pump would be better (or if they're the same) or if there's another i should get? i'm confused because my polo now has a 1.6 in it with twin 40 dellortos, cams, vernier pulleys, bigger valves and some other engine mods, including a nos kit (but i've taken the nos tank out and don't plan on using it).
I don't know much about fuel pumps to be honest but i know i need to get the right flow rate to balance with the carbs, any help?

Thanks, Michael

[hayesey]

the GT fuel pumps are the same as a G40 one already. 

[MichaelGT]

alright hah, thought that may have been the case, so would that be ok for the carbs etc. because it'll be able to take the extra hp?
also, where can i find one for a good price?

[gofasterpinch]

if you're running twin 40s, then i assume you have a fuel pressure regulator in the engine bay before the carbs?

the reason being, your twin 40s will want about 3.5 psi of fuel pressure, your standard GT pump will be pushing more like 120psi so even a replacement stock GT pump would be way over spec.

when i ran twin carbs on other cars (such as 200+bhp mk2 escort) we ran facet red top pumps which peak at about 7.0psi.

[hayesey]

is/was the car already working with a GT/G40 fuel pump or are you currently asking if we think it'll work or not?  I've also made the assumption that you are talking about the in-line pump and not the lift pump.

As Pinches says, an injection pump isn't really suitable for carbs as they expect to run at MUCH higher pressure.  But you can reduce the pressure using a suitable regulator.  Most people will use a pump specifically for carbs in the first place though, Facet ones aren't expensive at all.  Often people will keep the in-tank lift pump as normal and then use a Facet pump in the engine bay being fed by the lift pump.

None of this has anything to do with what power the engine makes, just the pressure the pump will run at.  To make sure whatever pump you use can cope with the power you need to look at it's maximum flow rate.  I don't know the figure for a G40 pump off the top of my head but it is good enough for over 200bhp. 

[MichaelGT]

i'm not 100% sure what pump is on it as i haven't removed it yet, but i think it's the original one :S and yeh it's the external inline pump sorry. i'm not too sure about regulators on the car to be honest, it was Jeff Seddon that built the engine so i've not got much of an idea. The car is running at around 170-180 bhp.

These are a few i've found so far;

http://www.fuelpumpsonline.co.uk/vw-polo13i-g40-main-pump-fuel-pump-1730-p.asp

http://www.fuelpumpsonline.co.uk/sytec-external-in-line-fuel-injection-pump-otp017-1931-p.asp

or one of the bosch ones: http://www.fuelpumpsonline.co.uk/bosch-fuel-pumps-original-16-c.asp

would one of these do?

[gofasterpinch]

170-180 bhp from a 1.6 on dellortos? with what other mods? 8v/16v??

[MichaelGT]

it's got a lot of other mods, cams, vernairs, bigger valves, and to tell you the truth i don't even know what else hah.
i don't even know what engine it is, it was built by Jeff Seddon, the guy with the twin vr6 700bhp mk3 golf B16DUB

[gofasterpinch]

i'd just replace the pump like for like, for a carbed application it will be way over specced.

is it an 8v or 16v? even so, 180bhp is optimistic.

[MichaelGT]

yeh think i'm just going for the original pump, it's got a pressure regulator and if it worked before then there's no point in using a different one.

it's a 16v, it was a totally handbuilt engine i think, the engine has only done around 5000 miles since being fully re-built.

i'll try to get it on the dyno soon to get a real idea, but that's just what i was told when i bought it