I’m facing an ongoing issue with my modified V8 engine, which is managed using the ECUMaster EMU Classic. Despite numerous emails back and forth with technical support, no solution has been found so far. I’m hoping someone here might have an idea about what the issue could be.
Summary of the Email Exchange:
1. Background:
• The V8 engine was converted from a carburetor setup to a turbocharged configuration with injection and wasted spark ignition.
• We’re using a 60-2 trigger wheel, and the injectors are set up in a semi-sequential pairing.
2. The Problem:
• To maintain a stable idle, we’ve had to set the ignition timing to 35 degrees BTDC. However, when adjusting to the usual 10 degrees BTDC, the exhaust headers start glowing red-hot after about a minute of running.
3. Support’s Suggestions and What We Tried:
• We checked the ignition timing using a timing light, ensured that the “First Trigger Tooth” was set to zero, and locked the ignition advance to 0 degrees as recommended. Despite all this, the issue remains unresolved.
• There is also an issue with battery voltage oscillating at higher RPMs, and the engine idles with a lambda value of 1.1, which isn’t ideal (should be closer to 0.98).
Current Status:
Despite following all the advice from the support team, including checking grounding and the voltage regulator, the engine still doesn’t perform correctly at idle, and we’re unsure what’s causing these issues.
Does anyone here have experience with similar setups or insights into what might be causing these problems?
This sounds like a timing mark/trigger setup problem to me.
Since you have mentioned that the engine was originally a carbureted V8 and your user name has z28 in it, I assume you have either a small block or big block chevy with an aftermarket/modified crankshaft pulley on it.
Did you physically check the alignment of your timing mark/pointer with cylinder 1 set at TDC?
Maybe your trigger setup is the problem:
„ensured that the “First Trigger Tooth” was set to zero“
Since you have a 60-2 Trigger pattern, every tooth is 6°. This would mean your sensor should point to the 9th or 10th tooth when the engine is set at TDC. Otherwise you are not in the
recommended “trigger angle” range.
Is your trigger angle setting in the recommended range of 50-60°?
Do you have a screen shot of your „Ignition – Primary trigger“ settings and maybe a picture of your crank pulley/trigger setup with the engine set at TDC?
If your engine doesn’t always ignite its charge, the measured lambda value means nothing, as the unburned charge will drastically increase the oxygen content in your exhaust gas, which will throw the measurement of.
If you have fitted a BIG camshaft, this will also be the case at lower RPM’s, even if your engine is running correctly, because of the large overlap a part of the fresh intake charge will end up directly in your exhaust gas.
The oscillating battery voltage at high RPM is probably a separate issue.
Is this measured at the Battery itself, or shown by the ECU? If
measured at the Battery, does this oscillation correspond with the voltage shown by the ECU?
If this corresponds it’s most likely a problem with your
alternator/generator or, if modified, with your accessory belt
pulley ratios, leading to an over/under speeding situation at the
alternator.