MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Necessity for Vacuum Advance

My limited understanding is that the vaccuum control unit on the distributor attaches by a tube to the carb/manifold assembly. My distributor vaccuum unit has no such tube attached, yet the car runs fine. How necessary is it to so attach the vaccuum unit? Does such attachment improve performance?

Regards,
M.D.
'57 coupe
M. D.

Vacuum advance does indeed improve performance although initial advance can be set to compensate for the lack of vacuum advance it often leads to hard starting and maybe pre ignition ping under load. Vacuum advance is just a method of tailoring the ignition timing to suit the load placed on the engine.
Yours was probably disconnected due to a leaking advance assembly by a PO. I'd check the assembly for leaks and if none, reconnect the vacuum line to the carb/manifold and reset the timing. I think you'll notice some improvement.
Bill Young

And it will be a lot more economical, finally repaired mine after 15 years and fuel consumption improved by 5 mpg out of town
martyn

This thread was discussed between 19/08/2005 and 21/08/2005

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.