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Ignition upgrades
https://www.slantsix.org/forum/viewtopic.php?t=25680		 Page 1 of 1
Author:  RamSST [ Sun Nov 04, 2007 12:39 pm ]
Post subject:  Ignition upgrades
Ok I went through the previous posts in a search and found alot about ignition upgrades but I'm curious which way is best for me?

I've always been partial to the msd 6al for an ignition box but with the limited options wasn't sure if there was a distributor suitable for that upgrade.

I've seen the pertronix upgrade

but I'm not sure what world be good for my turbo'd efi project?
Author:  SlantSixDan [ Sun Nov 04, 2007 12:59 pm ]
Post subject: 
Lots and lots of options. MSDs are good, HEI is good, Pertronix is good, Mopar electronic ignition is fine, Ford EDIS is good...which one's best depends on the nature of your build, intended usage, fuel system, budget, etc.
Author:  slantzilla [ Sun Nov 04, 2007 1:11 pm ]
Post subject: 
I have run a 6AL for years and triggered it with a stock electronic distributor. Many have triggered one with a stock points distributor too. :D
Author:  Shaker223 [ Sun Nov 04, 2007 1:32 pm ]
Post subject: 
I run an MSD 7A triggered by the points dist. with no problems.
Author:  RamSST [ Sun Nov 04, 2007 2:32 pm ]
Post subject: 
so what would I get if I wanted to run a MSD 6AL and upgrade from the stock points? I want my car to perform well and still have it run good and reliable for a daily driver
Author:  Matt Cramer [ Sun Nov 04, 2007 4:33 pm ]
Post subject: 
The key here is that it's a turbo/EFI build.

A turbo / EFI build is a rather extreme case; you've got to deal with a lot of cylinder pressure, and for best power and drivability, you'll want to use timing controls that advance under vacuum and retard under boost. While you could use a standard distributor plus an MSD BTM box, it makes more sense to place the ignition under the ECU's control and dyno tune it if you want maximum power.

So I'll base this around a computer controlled ignition. Two common setups, the Pertronix and the Mopar boxes, aren't readily adaptable to computer controlled timing. Triggering a Mopar box with a computer is a bit of a cobbled together deal, while the Pertronix would only work as a pick-up unless you did some major changes to it. EFI needs to be split into two areas: the input (how it reads the RPM and determines when to fire the plugs) and output (what it uses to fire the coil).

There's two good ways to trigger a computer controlled ignition on a slant six. One is to use a Lean Burn distributor - it has no advance mechanism and is pretty straightforward to set up. The other is a crank trigger setup. I started out with the Lean Burn distributor, but I think I might gain a bit of accuracy with the crank trigger. Particularly since I'm pretty sure there's nearly 200,000 miles on my timing chain! It'd be closer on a fresher motor, but a crank trigger opens up some distributorless ignition options, too. Your call here.

In another thread, you mentioned you were thinking Megasquirt. Here's the rundown on some of the possible ignition outputs you might pair a Megasquirt with.

VB921 controlling the coil directly - These are roughly equivalent to a typical stock ignition and likely to be a bit marginal for distributor + turbo applications.

HEI 7 or 8 pin module - Possibly a bit hotter than the VB921, but probably not ideal, either. It will depend on what brand of module and what coil you use. I originally used this on my Dart.

MSD 6 box - Ok, this one is a pretty hot setup. And it can be paired with a Lean Burn or any other slant six distributor.

Ford EDIS - This one might do pretty well, as it has plenty of time to charge its three coils, and they're pretty darn hot coils, too. The easiest distributorless ignition to set up.

Mitsubishi 3000 GT VR4 ignition - A somewhat more complicated distributorless ignition. Proven to work on applications up to 35 psi of boost.

GM LSx coils - Another hot factory ignition, and gives you the option of putting a nice row of six coils down the valve cover for some extra pizazz. About the same degree of complexity as the Mitsubishi setup.

I'm not entirely sure which of these setups is the hottest, but I am planning a MSD vs HEI vs LSx coil dyno test once the Dart's running again. My gut feeling is that on a turbo setup like this, you'll benefit from either having the extra coil charging time of a distributorless ignition, or a capacitive discharge setup that doesn't need a large coil charging time. An inductive discharge ignition (stock, Pertronix, HEI) with a distributor is held back by the limits on maximum dwell.
Author:  RamSST [ Sun Nov 04, 2007 8:27 pm ]
Post subject: 
What do you think would be best for me? should I build the motor for a turbo but run it in stages? I mean something like this:
1)Build the motor for turbo but just run efi perfect and tune
2)add Ignition timing perfect and tune
3)add turbo perfect and tune

Just so I'm not ruining all my work?


lol it sure helps understand something if I read it beginning to end. I've been reading about how to tune your megasquirt for street driving and I'm actually learning alot, and understanding more.

If I'm understanding right you tune individual sections of the programming so the engine runs properly and you have a specific goal to hit with slight changes

I'll follow this DIY Autotune crank trigger setup to see how it turns out before I decide what I'll use
Author:  RamSST [ Mon Nov 05, 2007 2:50 am ]
Post subject: 
Ok so I've read pretty much the whole writeups about MSII. Wow thats alot of stuff to plug. almost scared me away but I'm going to stick with it. the performance gains and power gains will be worth all the trouble. Plus I just like efi over carbs. And I think I've got the ignition pretty much figured out. :D this should be fun. I found a good dyno shop in my city here so tuning my megasquirt efi will be tuned the way the megamanual reccomends
Author:  Matt Cramer [ Mon Nov 05, 2007 5:40 am ]
Post subject: 
It's certainly not a bad idea to add mods in stages; that way you wouldn't be fighting several things at once. I'm not sure I'd bother dyno tuning it until it reaches the turbo form unless you want to practice tuning with an engine that's less risky.
Author:  RamSST [ Tue Nov 06, 2007 1:34 am ]
Post subject: 
ok sounds good to me. thanks guys.
Author:  RamSST [ Tue Nov 06, 2007 1:52 am ]
Post subject: 
ok so one thing I don't understand. If I wire up for 6 injectors are they all firing at once?
Author:  Matt Cramer [ Tue Nov 06, 2007 8:49 am ]
Post subject: 
Quote:
ok so one thing I don't understand. If I wire up for 6 injectors are they all firing at once?
They can if you want them to. You can also set it up so it alternates between 3 and 3. My Dart seemed to run better that way.
Author:  RamSST [ Tue Nov 06, 2007 10:53 am ]
Post subject: 
ok so setting up that way then it would probably be best to run them so that the 3 that fire are the 3 that are going to going to fire in a row. I thought they all fired on their own.
Author:  Matt Cramer [ Wed Nov 07, 2007 6:31 am ]
Post subject: 
Quote:
ok so setting up that way then it would probably be best to run them so that the 3 that fire are the 3 that are going to going to fire in a row. I thought they all fired on their own.
The current Megasquirt has two injector drivers and is a bank to bank system. While a sequential system can run a bit leaner at idle, I've found this still idles better than it did with a carb. I've paired my injectors with bank 1 driving 1, 2, and 3, and bank 2 driving 4, 5, and 6. Some others like all the odd numbered injectors on one bank and the even numbered ones on the other. I don't think it makes a big difference.
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