Fuel Lines

All the info you need to race E30's

Moderator: martauto

chips
Was Pzero
Was Pzero
Posts: 523
Joined: Tue Jul 04, 2006 11:00 pm
Location: Edinburgh

Post Wed Mar 10, 2010 10:15 pm

Because I started with a 316 carb car, I need to add a fuel return line back to the tank. Is it worth running new flow and return lines through the interior of the car instead?
MillRat
E30 Zone Newbie
E30 Zone Newbie
Posts: 249
Joined: Mon Dec 07, 2009 11:00 pm
Location: Santiago, Chile

Post Wed Mar 10, 2010 10:25 pm

Correct me if I am wrong, but isn't there already a fuel line to the tank even though it is carburettered? I know my E21 320 has a fuel return line.

Look for a three way fuel pressure regulator before the carby (it maybe mounted on the LH strut tower). Once the fuel pressure builds up in the fuel line to the carby, the pressure regulator then send any excess fuel to the fuel tank. Otherwise the fuel pump would be constantly fighting against a pressureised system and it would burn out very quickly.
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Cheers,
Michael.
chips
Was Pzero
Was Pzero
Posts: 523
Joined: Tue Jul 04, 2006 11:00 pm
Location: Edinburgh

Post Wed Mar 10, 2010 11:02 pm

Thanks Michael. It looks like you might be right, I've just never checked before and assumed that there was only a feed pipe.