Club G40 Forum

Technical => Electrical => Topic started by: Nick_S on March 06, 2012, 09:23:58 PM

Title: Uprated fuel pump
Post by: Nick_S on March 06, 2012, 09:23:58 PM
Looking at uprated fuel pumps to go with my 300cc red top injectors. What higher flow pumps have people gone for? The OEM G40 inline pump has flow rates 75 litres/hour MAX and 28 litres/hour MIN @ 300kPA pressure. There is a Walbro pump listed for the G40 as an OEM replacment which has a flow rate of 156 litres/hour. Is this going to be enough?

Anyone know the bosche part number of a G60 fuel pump on the off chance, so I can check its flow rates?

Cheers
Nick.
Title: Re: Uprated fuel pump
Post by: dub-disaster on March 06, 2012, 09:43:05 PM
I went for a sytec opt017 flows 135lph  max should be good for roughly 250bhp and was only £60 try  http://www.balancemotorsport.co.uk/main.asp?category=Fuel+System  (http://www.balancemotorsport.co.uk/main.asp?category=Fuel+System) really good for fuel pump sizing. That all said if i was doing it again id go for the walbro as it will flow more than i could imagine a g40 could use, give you plenty of scope for the future.
Title: Re: Uprated fuel pump
Post by: Nick_S on March 06, 2012, 09:52:44 PM
Yeah looked into the Sytec ones here

http://www.demon-tweeks.co.uk/performance/fuel-pumps/sytec-performance-replacement-injection-pump (http://www.demon-tweeks.co.uk/performance/fuel-pumps/sytec-performance-replacement-injection-pump)

but like you said, the Walbro has a higher output.

From what i can gather from a bosch fuel spreadsheet I found, the G60 inline pump is 172 litres/hour MAX
Title: Re: Uprated fuel pump
Post by: Andy on March 06, 2012, 10:55:42 PM
With 300cc/min injectors at 85% duty cycle (you won't get near to this) you're flowing 255cc/min per injector*, so 1020cc/min total.
*Assumes a linear relationship between flow and duty cycle.

1020cc/min = 61200 cc/hour = 61.2 litres/hour.

Add 20% headroom and you're at 73.4 l/hr, still within the spec of the OEM pump.

So 156 l/hr is plenty big enough, I'd avoid going too large, as the regulator can only return so much back to the tank and throttling back a beefy pump can do it more harm than good.
Title: Re: Uprated fuel pump
Post by: Nick_S on March 06, 2012, 11:06:50 PM
Haha if only i was better at the Math  ;D Cheers Andy, OEM pump is teetering on its limit so will uprate for peace of mind. That Sytec OPT017 looks very tempting now, but not at Demon Tweeks prices :D
Title: Re: Uprated fuel pump
Post by: Jezza-7 on March 07, 2012, 06:16:14 PM
Im looking to get one of them pump as well nick. Might be worth seeing if we could get a discount.


Title: Re: Uprated fuel pump
Post by: dub-disaster on March 07, 2012, 08:25:42 PM
Doubt you will get a discount there pretty cheap I've seen them for £55 in ppc mag
Title: Re: Uprated fuel pump
Post by: Jezza-7 on March 21, 2012, 09:59:46 PM
something like this?

http://www.ebay.co.uk/itm/SYTEC-IN-LINE-HIGH-PRESSURE-FUEL-INJECTION-PUMP-250BHP-/150778904831?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item231b1f80ff#ht_2738wt_956
Title: Re: Uprated fuel pump
Post by: dub-disaster on March 21, 2012, 10:13:05 PM
yup pretty much although mine was painted with opt017 written on it aalthough that may not actualy be the picture of the one i used. im tempted to upgrade to the walboro one for my future plans!! ;D