Mk2 Fuel System Questions

For all Carb and Injection engines, standard or modified plus non-standard engine transplants. Heads; Blocks; Cooling (including heater issues related to the cooling system); Mounts etc

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thxxx
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Joined: Fri Jul 17, 2020 2:12 pm
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Mk2 Fuel System Questions

Post by thxxx » Fri Sep 04, 2020 10:00 am

Hey, this is on my resto thread as well and I’ve done a bit of research but can’t seem to work out the answer.

So I have an engine with a DX bottom end, with a twin choke carb and lynx setup to go into the car when it’s complete. However, there is no fuel pump on the front, only a blanking plate, and no fuel vapour unit which on my other engine is mounted to the cam cover.

I am assuming the pump, as the DX block was from the injection engine if I’m not mistaken, has been replaced with an electric pump on the doner car? I don’t have access to it or would find out. I’m assuming I can put a new mechanical fuel pump into the blank if needed? Are there advantages to an electric one?

And the vapour collector seems to be missing entirely? Is this required? Has anyone mounted it anywhere else in the engine bay, or is it always mounted to the cam cover?

Thanks for any advice!



mr.brown
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Location: Surrey

Re: Mk2 Fuel System Questions

Post by mr.brown » Fri Sep 04, 2020 11:09 am

The mechanical pump on a carb car runs off a cam on the intermediate shaft. The DX doesn't have that cam.
Regardless I'm pretty sure the mechanical pump wouldn't be able to supply enough fuel/fuel pressure for a Weber 40/45 or similar.
You'd be better off biting the bullet and installing an electric pump (search Facet pumps) and a combined Filter/Pressure Regulator (search Filter King or Malpassi). Before buying make sure you know the spec of the carb and pressure required.



thxxx
Posts: 18
Joined: Fri Jul 17, 2020 2:12 pm
fill in the right answer: 15

Mk2 Fuel System Questions

Post by thxxx » Fri Sep 04, 2020 11:17 am

Ah thank you for this! Ill see if I can source the parts off the old car, and go from there.

It's a Weber 40 I think, but will double check. Does this then cover the vapour canister as well?

Édit: sorry, re-read. Looks like I will need both. I now have the pump off the other car but looks like I’ll need a regulator too. Thanks for the advice!