Hello, I have a question to ask about my XK120. I feel the car is a bit flat in its running. I tried a manifold pressure gauge on the car by fitting it to the tube out of the manifold for the windscreen washer. The gauge would only read 10" instead of the correct 18" at 750rpm. So I looked for leaks and could not find any ? It would only get to 18" at about 2,500 rpm. If I flicked the throttle it would go to about a high of 20" and low of 8". The engine has 9/1 compression and I checked the compression today as 180 to 190lbs on each cylinder. The timing is set at 10 BTDC and runs an electronic system by 123 of Holland. It has D type cams, 2x2" HD8's with UO needles, jet set about 1/8th inch down, volume screws about 6 turns up to run at 750rpm tickover to keep the engine smooth with the lightened Flywheel that chatters the gearbox at any lower tickover revs. When I start the car from cold with electric choke manual switch, it runs but only at about 500rpm until I give it some throttle to raise it to 1,000rpm which it will hold after about two minutes. I have tried every position of the nut on the electric choke, but it will never run at more than 500rpm at the initial start.
So, does all this mean some lack of suck in the manifold system ???
So, does all this mean some lack of suck in the manifold system ???