Weber DGV Noise

[Razor]

my engine/carb is now making a "rumble" sound after the carby swap
something like bru-bre-brap-bru sound when you let go off the throttle on speed around 60+ kph

drives fine though, idles good

checked the plugs (new), had it serviced


any ideas?

cheers

[A20A1]

It depends... how is your setup now... what vacuum lines if any did you keep. Have you upgraded the fuel pump... when you close the thorttle vacuum jumps sharply for a few seconds before it settles to normal... this spike will pull your vacuum advace making changes in the timing.

What rpm is the car at.
Normally slamming the throttle closed when the revs want to stay high will create a void so you might get some exhaust pops and some intake pops, especially if you are firing too early.

Make sure the PCV is still hooked up... other them that I'd need more info on your setup to make anymore assumpions on whats causing your noise.

[Razor]

vacuum lines are connected
engine is stock, fuel pump is stock I dont think I need a new fuel pump just for the weber swap as the stock pump can handle the weber fine.
it normally happens around 2500 rpm +
everything hooked up properly
no backfire from the exhaust or carby just that air noise.

[A20A1]

You sealed the coolant port on the manifold...?

[Razor]

I did seal the port