poor fuel consumption
Posted: Thu Jul 03, 2008 8:16 pm
Hi All,
I have finally lost patience. I have rebuilt the TC big valve with new just about everything, pistons valves etc...
I have overhauled the Dellorto carbs with new gaskets, seals etc, balanced using a carbtune. All jets etc.. are what they should be. The floats have been set correctly for float and droop level.
My ignition is spot on, and the internals of the dist have been replaced.
My problem is that the engine runs rich. I have turned the idle mixture screws in pretty much all the way, but the plugs and exhaust are always sooty black, and my fuel consumption is pants, around 10 -15 MPG.
I have an aftermarket Stainless exhaust that a PO has put on and I have been told by one or two sources that it cause lack of back pressure, resulting in an over rich mixture.
Question is do I fit a smaller idle jet from 50 to a 45? Change the back box on the exhaust? Or is there something I have missed?
Any suggestions gratefully received.
Kind regards
Jeff 72 +2
I have finally lost patience. I have rebuilt the TC big valve with new just about everything, pistons valves etc...
I have overhauled the Dellorto carbs with new gaskets, seals etc, balanced using a carbtune. All jets etc.. are what they should be. The floats have been set correctly for float and droop level.
My ignition is spot on, and the internals of the dist have been replaced.
My problem is that the engine runs rich. I have turned the idle mixture screws in pretty much all the way, but the plugs and exhaust are always sooty black, and my fuel consumption is pants, around 10 -15 MPG.
I have an aftermarket Stainless exhaust that a PO has put on and I have been told by one or two sources that it cause lack of back pressure, resulting in an over rich mixture.
Question is do I fit a smaller idle jet from 50 to a 45? Change the back box on the exhaust? Or is there something I have missed?
Any suggestions gratefully received.
Kind regards
Jeff 72 +2