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8mm fuel pump?
the_big_1 - 31/7/19 at 09:47 PM

Hi guys,

I now have my alloy tank etc. It has a 8mm fuel outlet. I have found a 8mm in 8mm out pre filter too.
What fuel pump can I use that's 8mm in, 8mm out to feed a 2.0l silver top zetec on original injectors?

Cheers!


big_wasa - 1/8/19 at 07:38 AM

It doesn't work unfortunately. And I have tried. High pressure fuel pumps like to be flood filled and do not like sucking especially through a filter. The fuel cavitates and the pump will scream.

If you have a flat bottom locost style tank then it makes problems even worse.

If the tank is new get it modified with a sump on the bottom and a 13~15mm out let.

Or

Get a swirl pot and use a low pressure pump from your new pre filter to fill it then a high pressure filter then pump to feed the rail.

Or

Get an internal pump ideally with some kind of surge pot.


coyoteboy - 1/8/19 at 09:43 AM

Had no problems with a BMW e30 inline fuel pump pushing through a pressurised filter, but the connector would need adapting.


the_big_1 - 1/8/19 at 09:49 AM

Hi Guys,

Had a quote of £30 to have the 8mm outlet that on the sump of the tank, changed to a 13mm one. This ok to input of high pressure pump, then out to high pressure filter, then 8mm pipe to fuel rail. Return back to tank 8mm.


40inches - 1/8/19 at 11:16 AM

If not using a swirl pot, the pump should be as low as possible,ideally below the tank with a very coarse/large mesh filter before the pump.
The best would be a large volume low pressure pump feeding the HP pump.


the_big_1 - 1/8/19 at 12:02 PM

I guess its a question of whats best?
Not planning to race etc.

A. Keep tank as is, 8mm outlet. In to filter, then LP pump. This feeds swirl pot like this? https://www.carbuildersolutions.com/uk/pressed-aluminium-fuel-swirl-pot-surge-tank. The from that to HP pump, Canister filter to fuel rail.

B. Change tank to 13 mm outlet. In to course filter, in to HP pump. Canister filter to rail.


B just sounds more simple to me?
Fuel pump in B would be level almost with the bottom of the tank.


adithorp - 1/8/19 at 02:37 PM

Go with b and get the pump as low as possible.


the_big_1 - 1/8/19 at 06:03 PM

Hi guys,

Could you recommend a short pre pump 10 mm in / out filter course type for before the HPpump? Also one for after the pump?


big_wasa - 1/8/19 at 06:04 PM

The swirl pot may be overkill for a road car but it’s future proofed if you go for more power and track work.
For your application, Spend a couple of quid more and get a sump on your tank and fit and forget.

I’ve been in one, same set up as yours and it would cough and splutter on roundabouts with less than half a tank of fuel




[Edited on 1/8/19 by big_wasa]


the_big_1 - 1/8/19 at 06:06 PM

Hi ya,

The tank I have has a sump. Just an 8mm pipe out lol


big_wasa - 1/8/19 at 06:19 PM

Job jobed then.

I thought I would get away with the set up you first asked about on my test stand. You can here the pump scream over the exhaust and induction. And you can see the bubbles in the filter.

https://youtu.be/afwiOZWXQKk


the_big_1 - 1/8/19 at 06:21 PM

Lol I know the feeling lol
Do you think with the sumped tank, converting it to a 10mm out let, to a pre filter, then to a HP with a filter after the pump will be fine?

Cheers!


the_big_1 - 3/8/19 at 11:39 AM

Hi guys,

Do you think with the sumped tank, converting it to a 10mm out let, to a pre filter, then to a HP with a filter after the pump to the fuel rail will be fine?


big_wasa - 3/8/19 at 04:50 PM

What size is the inlet on your pump ?

I am guessing 12mm ( 1/2" )

It’s not going to cost you more, why are you wanting to go smaller ?

[Edited on 3/8/19 by big_wasa]


the_big_1 - 3/8/19 at 05:42 PM

Hi,

Sorry I did mean 12mm lol. So the tank would be 12mm at the sump, 12mm filter then 12mm to pump. 8mm from pump the HP filter, 8mm to fuel rail


big_wasa - 3/8/19 at 07:53 PM

Yep, pre filter wants to be fairly coarse. But yeh that will fine.


the_big_1 - 3/8/19 at 09:43 PM

Perfect! Any recommendations on the pre filter?


big_wasa - 4/8/19 at 07:12 PM

No, I’ve gone the swirl pot route.

One guy on here used to recommend lpg filters. They come with 12mm ends and are dirt cheap. There are the expensive “motorsport” billet alloy filters at x10 the price and then some. Other people say wash the tank out and don’t bother.