Individual Deadtime Tuning Idea

Hey All,

I wanted to get some opinions on a technique I thought of for tuning individual injector deadtimes using ECMLink.

Basically, I would use a good quality infrared thermometer to measure the temperature of each exhaust runner right where it exits the head to see if there is a difference in EGT's between the cylinders, I can then adjust the deadtime for each cylinder to match them. My main goal for this project would be to improve idle quality and low throttle driveability.

My plan would be to create a jig to hold the thermometer with a rail that it could slide on to test each cylinder to ensure the distance between the point of measurement and the thermometer would be consistent. I would also run the test with the fans disabled and in a garage with the exhaust vented outside to ensure that the airflow over each exhaust runner is identical and the effects of convective cooling would be very small.

Do you guys think this could work? I really want to take advantage of this feature of link but so far there isn't a great way of tuning individual deadtimes.

Why not individual EGT sensors? There cheap enough these days?

I think I could do this significantly cheaper, that's the main advantage.

An infrared thermometer able to measure as high a temp as the runners will get too is likely more expensive than 4 EGT sensors. The $100 guns you find at most places definitely won't read that hot, or they never used to.

What gun/thermometer do you propose using?

I'm with Mike - just throw in an EGT sensor on each runner. Or if you wanna do it on the cheap then use one EGT sensor and switch it between runners although this would be incredibly inefficient and time consuming. If anything just buy 4 sensors and one or two gauges. Heck, you can find them used for next to nothing.

I haven't seen these really cheap sensors around, would you use 4 gauges as well? A link would be great.

I would start with making sure your injectors all flow the same amount first. Of course engine geometry and airflow will make a difference on individual injectors deadtimes.

And you are probably better off getting youself a meter with a thermocouple then using an infrared thermometer.

What's wrong with Thomas method of dialing in individual injectors? It doesn't use any external sensors and gets the job done relatively quickly to Thomass standards.

Just in case you wanted his method.

Individual injector deadtime setup

This relies on someone having a solid understanding of what they're feeling and/or hearing from the car. That and you're going based on a purely qualitative/subjective observation vs. something objective/quantitative. That's not to say you can't get decent results with it but it's not exactly a foolproof or ideal method.

Always a good place for EGT: http://www.aircraftspruce.ca
Plus, aircraft stuff on car = make car fly

Just like RedBull; they give you wings!!!

Ghislain

Have a better idea, why don't you just send the injectors to ecmlink, they flow test them & give you all the data to input global, voltage correction & individual deadtime?

Side note, we sell IR guns at work & they likely won't work for what your trying to do.

You might be better off tuning injectors with an O2 sensor. Trying to tune a cylinder based on egt is risky, this would be safer and much more accurate

http://carprogrammer.com/Z28/PCM/O2/IndividualCylinderFuelControlWithSwithingSensor1999-01-0546.pdf

The only problem is the cost is higher. You can still get fairly accurate with EGT if you know what you're doing (key point).

I know Kiggly runs an EGT and a wideband per each runner of his manifold.

AEM makes this which is perfect for this sort of stuff:

http://www.aemelectronics.com/?q=pr...s/4-channel-wideband-uego-afr-controller

Hey Guys,

It's been a few months since I started this thread and I've been doing some more reading on ideas for individual cylinder tuning, I came across this today.

http://www.carbtune.com/colortune.html

Basically its a clear spark plug that allows you to observe the combustion chamber while the engine is running. It can be used on 4 strokes and although it was designed for tuning carbs I don't see why it wouldn't work for a fuel injection system that has individual injector adjustment like ECMLink.

What do you think, should I give it a shot? I think using a wideband in combination with this tool could result in near perfect injector settings.

you would have to make custom plug wires to see thru the plugs. Do they even come in our size?

The kit comes with some sort of electrical extension that you plug your ignition wire into to fire the plug and keep a field of view open, it then has a viewing attachment that covers the top of the plug so you can look through it like a telescope into the combustion chamber. Standard size is 14mm thread so it should work. I think I'm going to buy one anyway to tune my carbed jet skis which also use a 14mm plug so I'll probably give it a shot on the talon too, I don't think it will do any harm.

I personally don't think it'll help where it matters.

At idle and cruise the ecu is going to change the air/fuel metering constantly in reference to the narrow band o2 reading, I guess you could modify the DA cells in those areas if the o2 sensor happens to be off a hair but I don't see the potential for much real world gains. It's a whole different ball game from carb tuning when you have an ecu measuring and changing things on the fly.

Where it matters most would be in WOT, when you're putting that trust into your wideband on being accurate, it would be nice to have a way to verify it is, but this is a point you wouldn't be able to monitor the site glass anyway.

It's a near product but I don't see a need for it in our application.