does anyone know what is a design gap between distributor rotor and cap posts for each cyl when rotor is just above it? I roughly measured both and it's about 2mm. Basically what I see with my cam at 3 degrees retarded:
my dyno tuner did some weird stuff and I'm catching a lot of mistakes, wrong injector flow/dead times would be the worst one. My VE table was weird looking so I went digging. All figured out and corrected.
Now I wonder if some knock he heard mid range that made him drop the timing was related to improper fueling.
But not what my question is about, I'm just second guessing everything that was programmed into this car by him now. So he made my Base IGN table like this: low tps regions 1-3 (I run AlphaN) above 2000 rpm-redline at 41' adv and 5% tps at 40 at the same rpm range. I've been having some throttle tip-in roughness after decel so I dropped the ignition down in those cells to 38 and 36 and all better now.
Just wondering if it's due to rotor to distributor contact limitations on M20? At his 41 degree setting, spark has to jump calculated 4mm gap from the rotor corner to the edge of the contact. At my current 38 and 36 btdc the spark gap is 3mm and 2.55mm.
- Rotor-to-cap terminal air gap: approximately 2.0 mm, calculated estimate, not physically measured.
- Rotor leading edge over terminal center: 25.5° BTDC (measured).
- Rotor trailing edge over terminal center: approximately 35–36° ATDC.
- Total rotor-to-terminal overlap range: approximately 31.6° BTDC to 42.1° ATDC, accounting for the 4.6 mm terminal width
my dyno tuner did some weird stuff and I'm catching a lot of mistakes, wrong injector flow/dead times would be the worst one. My VE table was weird looking so I went digging. All figured out and corrected.
Now I wonder if some knock he heard mid range that made him drop the timing was related to improper fueling.
But not what my question is about, I'm just second guessing everything that was programmed into this car by him now. So he made my Base IGN table like this: low tps regions 1-3 (I run AlphaN) above 2000 rpm-redline at 41' adv and 5% tps at 40 at the same rpm range. I've been having some throttle tip-in roughness after decel so I dropped the ignition down in those cells to 38 and 36 and all better now.
Just wondering if it's due to rotor to distributor contact limitations on M20? At his 41 degree setting, spark has to jump calculated 4mm gap from the rotor corner to the edge of the contact. At my current 38 and 36 btdc the spark gap is 3mm and 2.55mm.
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