Manifold question ??????

Chop Top VW Slammed & Awesome Dubber

91 posts · joined May 2010 · 1 Jun 2010, 6:56 pm

#782272

I'm installing a bugpak exhaust system and just relised that the holes for the two skinny pipes that come from the manifold are blocked on the exhaust system.
Are they necessary or is it ok to leave them blocked

thanks

71-BEETLE-SEDAN AKA Josh

1,058 posts · joined Mar 2009 · 1 Jun 2010, 6:57 pm

#782273

I believe that they are okay as they just use the radiant heat off the exhaust pipe.

Chop Top VW Slammed & Awesome Dubber

91 posts · joined May 2010 · 1 Jun 2010, 6:59 pm

#782275

thanks mate, what are they used for anyway

Joel Now containing 100\% E-Wang

9,368 posts · joined Feb 2006 · 1 Jun 2010, 7:11 pm

#782280

Definately drill them out

They're just left undrilled from the factory so they can be used with twin carbs

You'll end up with a pig in winter if you leave it undrilled

Extractors with preheat dont work terribly well as both side are positive pressure inlets where as stock only has one but it's still better than none at all

Fuel only burns properly as a vapour and going from a liquid to a vapour in the carb causes a refrigeration effect and the manifold ices causing really poor running
heating the manifold helps keep the fuel suspended as a vapour and stop icing

Bizarre Moderator The artist formerly known as blue74l

12,785 posts · joined Aug 2002 · 1 Jun 2010, 7:41 pm

#782294

Depends what carburettor you are running

If you are running duals leave them blocked

A single............hmmm...............Leppington................cold winters

The hard part is the undrilled ones are at an angle
REALLY dard to drill out

Futue te ipsum!!!

68AutoBug Beetle Restorer - Experience over 138\% - YIKES --

11,654 posts · joined Aug 2002 · 2 Jun 2010, 12:26 am

#782385

Chop Top VW wrote:I'm installing a bugpak exhaust system and just relised that the holes for the two skinny pipes that come from the manifold are blocked on the exhaust system.
Are they necessary or is it ok to leave them blocked

thanks

really depends on the temperature...
but I would drill them out and use the preheater

if Your temperatures aren't too cold, You won't need them
but its 6C outside here at the moment..
and will be even colder in the morning, so I really need Mine.

My beetle iced up last year going to the VW Nationals..
and My engine stopped....

so, for a little bit of fiddling...

LEE

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