[etdesrochers]

It just came back in stock I noticed yea. I bought some thanks! But the part is discontinued, would be nice to know a replacement for the future.

[pazi88]

Yeah. Buy the correct part from digikey/mouser and it will work correctly. I haven't searched alternatives for a while. But if memory serves me correct, there isn't really good viable options that have better availability than the STP75/62

[Dzeerve]

Hello again! even tho i have succesfully used your and other speeduino boards on other projects my own car with rev 2.1 board still gives me a headache. i am fighting with a wot misfire for a looong time, and finally i am getting some clue. today i upgraded to newer firmware and now it allows me to log measured dwell time and no surprise- dwell time drops at the same time when misfire happens. as you can see in this screenshot from my log
dwell time drops as low as 1.2ms even tho i am requesting 2ms in my tune. what could be the reason for measured dwell time be way lower than requested?

[NickZ]

Are you using a mega2560 MCU? with a 60-2 and either ignition or injection set to 6 cylinder the processor may be getting maxed out at high rpm and not having time to dwell the ignition channels.

[pazi88]

Are you using a mega2560 MCU? with a 60-2 and either ignition or injection set to 6 cylinder the processor may be getting maxed out at high rpm and not having time to dwell the ignition channels.

There is a lot of setups running that just fine and it's not really a problem. There is even 600-700hp setups running without misfires.

[pazi88]

Hello again! even tho i have succesfully used your and other speeduino boards on other projects my own car with rev 2.1 board still gives me a headache. i am fighting with a wot misfire for a looong time, and finally i am getting some clue. today i upgraded to newer firmware and now it allows me to log measured dwell time and no surprise- dwell time drops at the same time when misfire happens. as you can see in this screenshot from my log
dwell time drops as low as 1.2ms even tho i am requesting 2ms in my tune. what could be the reason for measured dwell time be way lower than requested?

Are you running the 202305 FW? The older ones have some random ign problems on these boards that might cause misfires at higher RPM.

[NickZ]

Are you using a mega2560 MCU? with a 60-2 and either ignition or injection set to 6 cylinder the processor may be getting maxed out at high rpm and not having time to dwell the ignition channels.

There is a lot of setups running that just fine and it's not really a problem. There is even 600-700hp setups running without misfires.

Mega2560 are not all the same, i've had good performing boards and bad performing boards, I have definitely had mega2560 boards that couldn't do the 60-2 trigger at high rpm

[pazi88]

Mega2560 are not all the same, i've had good performing boards and bad performing boards, I have definitely had mega2560 boards that couldn't do the 60-2 trigger at high rpm

You sure? The race condition problem in older FW was totally random and it was sometimes almost unnoticeable and in some cases it caused severe running problems.

[NickZ]

Mega2560 are not all the same, i've had good performing boards and bad performing boards, I have definitely had mega2560 boards that couldn't do the 60-2 trigger at high rpm

You sure? The race condition problem in older FW was totally random and it was sometimes almost unnoticeable and in some cases it caused severe running problems.

I referring to the quality of the mega chip on some of the cheap boards, I have had some that have underperformed, not the firmware.

Im not saying every mega2560 is going to have a problem, but the quality of board DOES make a difference.

[iltheo84]

dwell time drops as low as 1.2ms even tho i am requesting 2ms in my tune. what could be the reason for measured dwell time be way lower than requested?

Looks like the very same issue I have my Speeduino install in my Miata.
DIY EFI Core4, stock-ish 1.6L engine, misfiring at WOT upwards of 5000rpm.
I still have no solution.