V8 Fuel pump advice

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3Diffs

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Northants
Hi All, forgive me if this has been discussed before, I couldn't find a thread. I'm rebuilding a 89 110 ex military V8 to EFI spec. Its got the metal tank with separate sender. I've extracted the fuel pump as its U/S and it looks pretty weedy. Is there a simple upgrade one that fits the hole? The Disco combined pump/senders look too wide in the pics and presumably have to go in a plastic tank? Or maybe I should switch to a plastic tank/pump?
 
I think this means you have an in-tank pump?

I've got a 90 - so this won't exactly work for you since our tanks are different...but the same approach should work I think...when I converted mine from carbs to EFI, the main change was I bought a range rover classic in tank pump. I kept the top half of the 90 in tank carb low pressure pump (bit that fits the tank), but the bottom half is now from a range rover classic efi. It was just a 5 minute nut and bolt job to switch the pump units over from low pressure to high pressure.

Worked well and been in use on my 3.9 EFI since 2008. Make sure you upgrade the fuel hose though and use a decent pipe clip on the tank fitting.

(Have a look at the parts diagram - I think it was a RR one, but I actually can't remember. It looked similar on the parts diagram so I had a punt and it worked)
 
@3Diffs , you need the following components to make the EFi conversion work properly, have correct flow volume and pressure, and to not suffer fuel starvation both under standard road use and when turning corners/off road with lower fuel levels
  1. from tank, large capacity fuel filter #1 to low pressure lift pump to fuel catch tank
  2. from fuel catch tank to large capacity fuel filter #2 to EFi high flow fuel pump to
  3. high pressure flow fuel lines to injector rail/injectors
  4. if using std RV8/RR EFi rail this has a constant/fixed pressure regulator on the return :. no need to add additional under bonnet pressure regulator
  5. high pressure return fuel line to fuel tank return - the return line should be of increased i.d to that of the flow line to ensure minimum fuel return to tank resistance
  6. although the EFi fuel cct is effectively a closed loop system it still need atmospheric relief - this is via your fuel filler cap :. you'll need a cap of known/new condition
Note: do not skimp and fuel filters, they are critical components and guard against premature fuel pump failure
 
Thanks guys for advice. I've laid new Kunifer lines out and back and my thoughts before your reply was to use a new carb V8 in tank pump to do the lifting then boosting it at the firewall with a high pressure pump rather like moderns use. Will digest the above. Couldn't agree more on the filters V8250, the number of cars I've seen where its never been changed(!)
 
This may help a little, my "tuned..." TVR 4.0 Griffith engined MGB Sebring mid build of the fuel set-up [Centre Top LP filter to LP FACET Red Top to Catch Tank, to HP Bosch 044 Pump to HP Filter to engine] The catch tank top outlet is the overflow return to the fuel tank.

I used HP lines, then through fixed bulkhead unions to insulated Kunifer copper lines [8mm flow, 11mm return - ultimately, the fuel lines control peak flow via their I.D.s/CSA's giving some 19% over peak flow rate at 263bhp.

You'll note I've added rubber sleeved filter/pump mounts, this to ensure minimal pump buzz/vibration through boot firewall to passenger cockpit.

upload_2022-2-8_18-30-11.jpeg
 
This may help a little, my "tuned..." TVR 4.0 Griffith engined MGB Sebring mid build of the fuel set-up [Centre Top LP filter to LP FACET Red Top to Catch Tank, to HP Bosch 044 Pump to HP Filter to engine] The catch tank top outlet is the overflow return to the fuel tank.

I used HP lines, then through fixed bulkhead unions to insulated Kunifer copper lines [8mm flow, 11mm return - ultimately, the fuel lines control peak flow via their I.D.s/CSA's giving some 19% over peak flow rate at 263bhp.

You'll note I've added rubber sleeved filter/pump mounts, this to ensure minimal pump buzz/vibration through boot firewall to passenger cockpit.

View attachment 258621
NICE! We're into B/C's too. I keep tripping over my MGC bonnet each time I go in the workshop, I really must do something with it!
 
Early Range Rovers use the same tank as 110's, so presumably Discovery V8 tanks can be made to fit 110's as well. I think that the main difference is that there is a strap that goes over the top of the plastic Discovery tanks.
It could be worth fitting the tank and fuel pump that matches the engine that you are using.
 
Early Range Rovers use the same tank as 110's, so presumably Discovery V8 tanks can be made to fit 110's as well. I think that the main difference is that there is a strap that goes over the top of the plastic Discovery tanks.
It could be worth fitting the tank and fuel pump that matches the engine that you are using.
 
Yes one of the options was to go plastic and what you say about the pump matching the engine makes sense. Does anyone know if the plastic tanks have baffles? The steel on in situ is baffled.
 
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