On ECU equipped cars without idle control valves, ignition timing is usually used to maintain a target idle as temperature increases.
The key to getting you timing right throughout the rev range is to achieve a 50% burn by 20deg ATDC (I think). Depending on the speed of your flame front you have to place the spark at a certain point of the rotation to achieve this. As the engine revs go part 3700 you will need to continue advancing the timing in order maintain the 50% burn by 20deg ATDC. The likelihood of an engine pinking will reduce as the revs rise so you can usually get away with more advance in the higher range.
Johny, this is great food for thought, thank you. I've often wondered why the curve stops advancing at 3k ish. With all I've read, I'm pretty sure the engine needs more advance further up (albeit subtle) but I assume it's to do with what they could achieve with springs and weights in those days and playing safe.
BTW - I thought this was a great read.
http://www.enginebuildermag.com/201...g-making-maximum-power-means-knowing-science/
can't blame me, I would have made you get the Kameari one with fixed timing and a massive starter motor!
Well you did suggest the 123 after all [emoji14]
123Ignition dizzy. No mechanical parts, app controlled via Bluetooth, with the extra features Ali mentioned. Made in the Netherlands. Been thinking about one for the FairladyZ. Even had the app on my phone to play with!
Did it come with the correct Z mounting bracket and drive cog to engage with the fuel pump drive?
The app is very cool indeed - much fun to be had. I like the real-time tuning which will come in handy when I'm next on the rollers at the tuning place to optimise, see the difference a little extra or little less here and there would make.
This is what it came with which I need to figure out, hence not on the car yet. But it looks fairly straight forward. The instructions are a little generic so I may do a write up on it and send the to 123 to adapt / include with the Datsun package.
@woody - you have far bigger fish to fry my friend and don't need the added expense of this if your car is running as it should!
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