quote:

Originally posted by BJs Wild Ride:
Gotcha.

It’s also possible to use a standard pickup in the distributor for the crank sensor and then use the rotor as a cam sensor. I think Ive seen a kit for sale somewhere but it’s a lso possible to fab your own.

Looks like there might be A third option that I’ve never heard of before is to use a missing tooth cam trigger as your only trigger. I’m not sure if Haltech can handle this but apparently mega squirt can so others must be able to as well.

https://www.stinger-performanc...ensor-conversion-tfi

I could be wrong, but I think that is considered running "wasted spark". Since it doesn't know which cycle the crank is on, it fires every cycle, just wasting the other spark. Which is what most of us did with regular ol crank triggers. IMO, unless maxing out the cop's power wise, or running sequential fuel injection, there shouldn't be a big need for the cam sensor. Somebody correct me if I am wrong. I missed coffee this morning.

Bucky, I don’t think you can run CNP as waste spark with a standard crank trigger. You have to identify when #1 is somehow. That missing tooth cam trigger I linked to specifically says it’s for sequential stuff. You could tell where the engine is at if you set the missing tooth of the cam trigger to 60 degrees btdc and then tell the computer that. All of these cnp and sequential systems are running algorithms to identify how fast the engine is spinning and where it’s at in the rotation to determine when to fire which coil. It’s not like a 7al2 or whatever that just fires as fast as it can when it sees a trigger.

The big deal on the standard cam/crank CNP deals is that the cam sensor pulse is far enough away from a crank pulse. On the LS stuff it’s not incredibly uncommon for an aftermarket crank trigger wheel to be rotated far enough from factory alignment that a crank and cam pulse line up. If this happens, none of these standard systems (Holley, Haltech, msd 6014) is going to fire the coils because they all look for the cam pulse to fall between 2 crank pulses to figure out where the motor is at in its rotation. Now, there may be some exceptions where a system is specifically designed to read something like a stock gm 58x wheel because it has assymetry to show the ecu where it’s at. This might make it possible for the computer to fire in waste spark mode because it knows where the crank is but not whether it’s on compression or overlap stroke.

Sorry, I know most of this isn’t relevant to Dave’s questions, just thought I’d try to share some of what I think this old dinosaur has learned about the new fangled tech. 10 years ago I swore I’d never let a laptop near my race car…

quote:

I don’t think you can run CNP as waste spark with a standard crank trigger. You have to identify when #1 is somehow.

True Statement. For this to work as waste fire, the rotational trigger device could not have more than 2 triggers per revolution.

quote:

Originally posted by BJs Wild Ride:


Sorry, I know most of this isn’t relevant to Dave’s questions, just thought I’d try to share some of what I think this old dinosaur has learned about the new fangled tech. 10 years ago I swore I’d never let a laptop near my race car…

Don't mind me.. I always learn something from almost all conversations..

Dave

quote:

Originally posted by markemark:

quote:

I don’t think you can run CNP as waste spark with a standard crank trigger. You have to identify when #1 is somehow.

True Statement. For this to work as waste fire, the rotational trigger device could not have more than 2 triggers per revolution.

Wouldn't a 60-2 toothed wheel identify exactly where the crank is?

You can use the cam sync plug you listed (85231) for your cam signal, and your MSD crank trigger with a 554-118 hall effect sensor for your crank signal. It is pretty simple to wire the sensors. You need a Holley 570-204 connector (it comes with the pins as well), and there are only 4 wires that are used for the 2 sensors (each sensor is 3 wires: 12v, ground, and signal). On the 570-204 and matching MSD connectors, pin A is the 12v for both, pin B is the ground for both, pin C is for the cam signal, and pin D is for the crank signal. The other loose wires get hooked up according to the MSD instructions. As for the coils, LS coils are smart coils, and are not suited for waste spark (paired cylinders firing together: 1/6, 8/5, 4/7, 3/2) and can burn out quickly. A waste spark uses dumb coils, which are suited for the shorter charge time. A missing tooth crank wheel can run in waste spark, provided the ignition system has that option available in the software (the 6015 does not), and the coils are correct. The cam sync is needed to tell the system where number one cylinder is so that it can fire sequentially. I would never recommend using a dual sync in any race application. If you have any other questions, feel free to ask.

quote:

Originally posted by Bucky:

Wouldn't a 60-2 toothed wheel identify exactly where the crank is?

I suppose you’re right.

Besides botmbulbs comment about duty cycle, I would also add that I would not recommend running waste spark on any boosted methanol setup. I accidentally enabled waste spark on my Haltech even though it was triggered properly for sequential CNP operation (another Haltech “feature”) and almost burnt my garage down.

quote:

Originally posted by BJs Wild Ride:

quote:

Originally posted by Bucky:

Wouldn't a 60-2 toothed wheel identify exactly where the crank is?

I suppose you’re right.

It will only tell it where TDC for #1 and #6 is. It won't tell it whether it should fire #1 or #6. Crank turns twice for every cycle, cam turn once. That's why you need the cam sync, so it knows the difference between #1 and #6.

quote:

Originally posted by botmbulb:I would never recommend using a dual sync in any race application. If you have any other questions, feel free to ask.

Agreed. Some racers whether using analog or digital, are still using, and swear no performance difference with distributor trigger.

Would you list the Holley part number for the mating male plug with pins to the Holley 570-204 connector?

quote:

Originally posted by markemark:

quote:

Originally posted by botmbulb:I would never recommend using a dual sync in any race application. If you have any other questions, feel free to ask.

Agreed. Some racers whether using analog or digital, are still using, and swear no performance difference with distributor trigger.

Would you list the Holley part number for the mating male plug with pins to the Holley 570-204 connector?

Dual syncs tend to have issues above 6500 rpm.
The mating connector is 570-203.

quote:

Originally posted by botmbulb:

quote:

Originally posted by BJs Wild Ride:

quote:

Originally posted by Bucky:

Wouldn't a 60-2 toothed wheel identify exactly where the crank is?

I suppose you’re right.

It will only tell it where TDC for #1 and #6 is. It won't tell it whether it should fire #1 or #6. Crank turns twice for every cycle, cam turn once. That's why you need the cam sync, so it knows the difference between #1 and #6.

Right. That's the waste. It's firing them both. One needs it, the other is wasted. Maybe I'm looking at it wrong, which is always possible.

In a wasted spark system, the spark plugs fire in pairs, with one plug in a cylinder on its compression stroke and the other plug in a cylinder on its exhaust stroke. The extra spark during the exhaust stroke has no effect and is thus "wasted".

But again, it's always possible for me to look at this incorrectly.

This message has been edited. Last edited by: Bucky,

quote:

Originally posted by botmbulb:
You can use the cam sync plug you listed (85231) for your cam signal, and your MSD crank trigger with a 554-118 hall effect sensor for your crank signal. It is pretty simple to wire the sensors. You need a Holley 570-204 connector (it comes with the pins as well), and there are only 4 wires that are used for the 2 sensors (each sensor is 3 wires: 12v, ground, and signal). On the 570-204 and matching MSD connectors, pin A is the 12v for both, pin B is the ground for both, pin C is for the cam signal, and pin D is for the crank signal. The other loose wires get hooked up according to the MSD instructions. As for the coils, LS coils are smart coils, and are not suited for waste spark (paired cylinders firing together: 1/6, 8/5, 4/7, 3/2) and can burn out quickly. A waste spark uses dumb coils, which are suited for the shorter charge time. A missing tooth crank wheel can run in waste spark, provided the ignition system has that option available in the software (the 6015 does not), and the coils are correct. The cam sync is needed to tell the system where number one cylinder is so that it can fire sequentially. I would never recommend using a dual sync in any race application. If you have any other questions, feel free to ask.

Thanks..

Pretty much the conclusion I have arrived at..

Dave

anyone messed with megajolt?

Been contemplating it on a rons injected ford.

quote:

megajolt

Looks like it uses Ford coil packs, one coil per 4 cylinders.
Is the output as good as the 8 coil packs like other systems?

dave