My recent 320 mile round trip to Arch Motors was my first long journey in the 7, giving me plenty of time to appreciate the car's idiosyncrasies. My only real complaint is the engine's part throttle histrionics. "They all do that Sir" seems to be the general opinion on the forum but I can't help but think things can be improved somewhat.
Refurbishing the 40 DCOE's is next on the to do list, but before I do I'd love to get advice from forum members on getting the engine to run more smoothly on part throttle. I suspect a lot of the problem is due in part to having a distributor optimised to give an ignition advance curve that produces maximum engine power output on full throttle rather than smooth running on part throttle.
My 1700 Supersprint engine is standard, specified with the optional 4 into 1 competition exhaust and Lucas High Performance ignition system, and it is in good health with all compressions around 160psi. It has subsequently been dry-sumped and at some stage the distributor was modified by Roger King - bob weights and springs changed to alter the advance curve perhaps? Instructions are to set the timing to 35degrees BTDC at 5000rpm).
I have quickly set the idle mixture and balance with a manometer, with the only observation being that the two outside chokes are drawing a tiny bit more than the inner ones which I'm sure would be sorted with the rebuild.
I came across a detailed post from one member saying replacing the main jets to 130 (originally 120), air correctors to 180 (165) and idle jets to 50F9 (45F9) really helps matters. Have any other members tried this or can offer other suggestions that have worked?
Thanks in advance,