I have just changed the original twin carbs on my 1973 Bays 1700 Engine for a single Empi 32/36 progressive carb kit from VW Heritage . everything works better but now revs increase when I put my foot on brake...Is it a problem with the servo (bit of a coincidence) or is it the new carb and pipework..maybe letting in air ?? Or something else ?? Cheers ian
Servo pipework is leaking or servo is leaking. Get those original carbs back from over @snotty 's fence and start refurbishing them for when the outside air temperature drops below 20 degrees C and your mistake becomes obvious. You will be posting "it hesitates and runs like a dog" in a couple of months so you might as well get fixing that problem now. You started with a perfectly designed but troublesome and possibly worn out set up and now you have fitted a bodge that is just wrong for your engine. Good luck but expect more trouble with that carb/ engine combo.
Get a smaller pair of shoes! You are probably catching the accelerator pedal when you have your foot on the brake!
