The Ignition Pages

This area discuss some of the ignition options that are available on GenBoard. Along with that, are discussions about timing technique, parts, availability, and other research.

Ignition Topics

EdisIgnition - Ford EDIS System where we calculate the spark advance, send (1536 - spark_adv_degrees * 25.6 ) usec SAW pulse to EDIS, and EDIS takes care of the actual ignition timing relative to crank position, dwell control and spark generation. EDIS uses it's own VR input from 36-1 timing (crank-)wheel so you'll have to add this to your crank.
DwellControlIgnition -
DummyIgnition - Taking care of dwell control. To make sure the coil is charged sufficiently.
IgnitionPage/COP - Coil Over Plug technologies.
IgnitionPage/TransformerWithAmplifier - coil with builtin driver
TimingLight - See this page for a very simple DIY timing light


Q: are the COP off a BMW M5 3.5,3.6, or 3.8ltr diffrent?

what do

measurements suggest? If they fit mechanically, there shouldn't be any difference electrically. Maybe minor difference in dwell, but hardly anything that couldn't be configured easily.

Q: how can I use GM LS1 (???) smart coils which have built in drivers. Can you get some links to the documentation ? Maybe aliases (other names for the same , part numbers) ?

In the worst case, you can scope the signals while running on an alien system, and test on the table to verify.

Is there any chance that there is no such thing as "GM LS1 smart coils" because LS1 is a car (corvette?) ?

LSX are 3rd gen chevy engines

LS1 >> C5 corvettes, 98+ f-bodys, Holden Munaro, Commodore and ( chevy caprice and lumina in the Middle East)

LS6 >> Z06 corvettes

LS2 >> C6 corvettes and 2005+ pontiac GTO

LS7 >> will be on corvette Z07

there are also 2000+ truck VORTEC engines that have the same ignition system but with hotter sparks

each of these engines has 8 coils "CNP" and uses a variable reluctance type camshaft position sensor


I've read that these coils have built in drivers and considred as smart coils






download this pdf file it has some info about LS1 ignition system

[LS1.pdf Dead Link!!] According to the drawing the "smart coil" has an NPN inside (maybe same type that Keith bought the other day). However it might just be a draft. It's easy to verify (eg. with DVM: the Base-Emitter of an NPN drops about 600mV).

Here, you can buy several ignition coils, wires and several usefull things: http://www.nology.com/products.html

Runtime switch between maps

The VTEC Honda uses 2 different and independent ignition and injection tables for low speed cam profile and for high speed cam profile.

Multiple maps already exist (since 1.0.29 or so?): Save / Load config and tables from a particular slot via

command. Replace the dot with 0..9 (1 digit, maybe not 0..9 just 0..3 so max 4 can be saved, not 10 different set of maps and config). The slot '0' gets loaded at boot (or saved with megatune or with mcs command). This might be useful (eg.) with different fuel (ignition advance) or if the same ECU is used for different engines and can be reconfigured with 4 keystrokes with a PS2 (without notebook).

However, in some cases it would be nice to switch between maps according to an input (voltage-level) condition (eg. when cam changes to high-RPM profile, or with a driver actuated dash-switch).

Controlling the honda VTEC does not needs such input, since the ECU switches cam-profile according to loadsite and the loadsites can be configured (similarly: I'm using longer runner length at certain RPM and MAP, notably 1000..3000 RPM and MAP > 80kPa ; and have those cells set up for the right VE and ignadv); The feedback from the actuator is useful if the actuator is likely to fail or if the actuator has an unpredictable delay.

AFAIK there's no pressing need to have VEMS switch maps during runtime. But that feature might be appealing to some, so a good candidate for firmware development (even if some will just use it to shoot himself in the foot).

I have things I want done too. I have asked for them, and they seem to be in progress. It just takes a little time, and it's never quick enough is it!?!