Timing curve for a modified 283

[Nick_nl]

Hi Guys,

I have a question about the current timing curve for my engine.
It a 57 283 with a mild cam and aluminum heads and ramshorn exhaust manifolds.

* Cam Lunati 60100 207 in 213ex at 0.050 112 lobe sep.
* Head Trickflow super 23 175
* Intake Edelbrock 2703 with a Holley / QFT Brawler 570 vac sec

The distributor is a aluminum points distributor with a pertronix II installed.

RPM Advance
500 12* (24* with vac advance in Drive)
750 17* (33* with vac advance)
1000 21*
1250 23*
1500 23*
1750 27*
2000 30*
2250 30*
2500 30*

All in is at 2000 with these springs. How do i determine if this is OK? I didn't hear any pinging, but the i can?t drive the car at the moment.
I might have to elongate the slot a bit to get the last degrees.

Thanks Nick

[Rick_L]

You need to set up your timing curve with the vacuum advance disconnected, then connect it up and do it again.

The ignition timing you need is dictated by the engine compession ratio, fuel used, and camshaft timing.

The engine won't ping just running it with no load. You need to drive the car to create a load if you're going to check for pinging.

[Nick_nl]

ok, I did set the timing with the vacuum plugged, only the two mentioned are with vac advance.
The fuel used is RON 98, should be close to us 93 octane. The compression is 9.33:1 with this cam it gives 8.02:1 dynamic compression ratio according to the wallace racing calculator.
The driving part will be for the next year, the weather is not really nice at the moment.