[Rusty85]

If I don't really get the speedy going with the "stock" setup I'll be a bit disappointed but the main reason I've gone into it is for the "next" engine I'm slowing getting parts for. I have a vortec distributor for the oil pump and cam sensor and a 60-2 wheel for the crank. I'm planning on using LS coils for paired injectors and wasted spark. I didn't want to put together the new wiring harness until the engine and fabrication is ready and that will probably be a few years down the road.

[PSIG]

You seem to be on a reasonable track; but we can't see what Speeduino thinks it's doing, or how it's responding, without a log and the tune used to take it. At this point, it's like a spectator sport on the radio.

BTW, I had a session where I was assisting a tuner on his project, and we were going crazy. The timing was not where it should have been. We put a measured timing mark at 30° on his damper and shot it with the dial-back light at zero. Perfect timing.

We verified with another light. I guess his light was dropped once too many. Whenever I hear about timing issues, this is one of the first things I think of (of course), and suggest you test yours — just in case.

[Rusty85]

I do have a second "dumb" light I could try that with. So far this light has been fairly reliable and I've used it on several vehicles with carburetors and FI. It can add its own "jitter" (maybe 1/2 a degree) over 30 degrees of advance but I'm not worried about 1-2 degrees of jitter, I'm more concerned with the 6-12 degrees I'm seeing under 1k. The timing is still absolutely correct at 1k+rpm. I have a few changes to test out with a friend (so I'm not running back and fourth) and I'll post all of the logs/observations/changes we try out. I could see some bad data ending up here or there after X number of small changes so I'll try another reflash before I start.

[Rusty85]

While testing with a friend, it looks like the timing is only dropping 4 degrees when the rpms are falling now. Thats completely usable in my opinion. I tried switching to use the tps instead of VE to get the idle stable at lower rpms but making it leaner or richer didn't really help any. It was decently stable with the GM VE curve with a bit subtracted so I'll go back to that and see what happens. I took logs but they're not particularly useful from what I saw. If I can get the idle stable with the speeduino disconnected from timing (what I tried in the first place) I'll get some logs both connected and disconnected.