I am trying to get more fire to my 327/350 '67. I replaced the points with the Lectric Limited breakerless conversion. I plan on installing a MSD 6A box and mounting it between the radio and firewall. Would welcome input on does and don'ts of wireing it to my stock motor and wireing harness except for the points conversion.
-
-
Re: MSD ignition installation on 67
If you haven't bought it yet, consider the following points of wisdom from my 40 years of reading IC engine textbooks and SAE technical papers.
1. Once sufficient ignition energy is available to consistently ignite the mixture, further energy is of no value, however, all systems have excess energy to provide reliable ignition with deteriorated components.
2. Road engines that idle and spend a lot of time at low load need long duration sparks because exhaust gas diluted and low density mixtures are more difficult to ignite than rich, dense mixtures.
3. The Delco single point spark duration is about 120 microseconds, which is typical of point type inductive ignitions. Inductive electronic systems are usually greater because of greater ignition engery. A typical CD is about 35.
4. ALL OEMs currently use inductive ignition systems in production cars.
5. Multiple sparks are of marginal value because succeeding sparks are significantly retarded from optimum timing. You need a system that lights the fire with one properly timed spark 99.999999999999999999999999999999999999999 percent of the time.
If you need "more fire" with a electronic switch replacing the points, then there is something wrong with your ignition system. Give the distributor a good overhaul/blueprint and check the coil, ballast, and wires for conformance with OE specs.
Distibutor overhaul and blueprinting is discussed extensively in the archives, and it is a relatively easy job as is checking and replacing other OE igntion system components.
Duke -
Re: MSD ignition installation on 67
The only thing I have changed on my original owner 68 327/350 are the spark plug wires. I like the aftermarket sprial core wires. Have had them on it for about 20 years. Original point type ignitions are reliable.Comment
-
Re: MSD ignition installation on 67
Chuck - Like Jim, I'm original owner of '67 L-79 4 sp. I understand you're wanting to 'get more fire' to the engine, but the rationale behind that is unclear in your post.
First off for me, this particular motor is an incredibly dependable power plant. I have always kept is completely stock, and believe me, it runs strong and never, ever, ever coughed when I asked for power. It starts hot or cold, and idles smoothly. Electrically, be sure to keep the OEM settings dead-nuts right-on. Timing, dwell and plugs.
Duke's post nicely addressed the technical aspects of this issue.
Perhaps the motivation to 'get more fire' may actually be caused by some other engine system, such as fuel. Or perhaps the MSD device you cite offers some benefits that I'm unaware of. If so, have at it.
In any event, without understand your performance goal, I would say start with the basics. In my experience, it will run just fine per OEM.
Good luck.
TomComment
-
???
I guess I don't understand why you want to install BOTH a Breakerless SE and an MSD 6A. The Breakerless SE is already a solid state ignition system featuring precision spark timing and stable output (with a self-compensating dwell feature for accurate high RPM spark)...
If memory serves the MSD 6A is a capacitive discharge based, electronic ignition system that provides most of the features you've already got. About the only feature that's not included would be the rev limiter function that's part of the MSD 6L.
I don't think it's wise to try and 'gang' two electronic ignition systems and for typical to aggressive street use, I'd say just stay with the Breakerless SE. Now, if you're into off-road competition where you really want the rev limiter protection (blown shift), then remove the Breakerless SE and run the MSD system by itself.Comment
-
Re: ???
We have found that the MSD box used with their coil enhances the performance of most street engines. If the car is a point ignition, I just leave the points in. They last forever. My wife's '72 has a set of points that have been in for over 15 years and they still look like new. Usually you will see an increase in idle speed of 200-300 rpms after addition of the coil and box. Fouled spark plugs are a thing of the past.
We have used these on every car that we put through the PV process until the Judging Reference Manual specifically barred the installation. You can install this system on a '66 425 hp with a '67 L/88 cam and idle the engine at 750-800 rpm's with no problemsDick WhittingtonComment
-
Re: MSD ignition installation on 67
Thanks for all of the good advice. I seem to foul plugs to often and was just looking for a remedy. I am going to go back to points and try the MSD box and coil. Has anyone wired one lately? I have a diagram but thought someone had some practical advice for wireing.Comment
-
Re: MSD ignition installation on 67
Small Orange + coil
Small Black - coil
Small Red (To the wire you took off + side of coil or better to the ign. side of resistor to get 12v)
Small White (To the wire from your dist.)
Big Red + Battery (ONLY)
Big Black - Battery (ONLY)
Make a small metal plate and mount standing up under battery, paint black, tape wires. You'll never see it. Have always run 7AL2 on race cars and 6A on street cars. Works great even using points as a trigger. Go ahead and get Blaster 2 coil.Comment
-
Re: MSD ignition installation on 67
What spark plugs are you using?
AC heat range "5" or equivalent in another brand is best for normal driving. The OE heat range "4" is too cold, and heat range "3" will foul out in a couple of hundred miles of driving.
The best way to solve a problem is to find the root cause and correct it - not just keep adding expensive band-aids.
DukeComment
-
Re: MSD ignition installation on 67
Thanks Dana and Duke just changed to AC 45's from 43's and then changing to MSD and figured I would be all set.Comment
-
Re: MSD ignition installation on 67
To echo what Dick said, I installed an MSD on my dual carb '61. The plugs fouled, especially on trips to the mountains. The MSD keeps the plugs clean. I know it is treating the sympton rather than the root cause, but I have never chased down the spare jets and metering rods for the WCFB carbs. It helped with the performance since it was not misfiring as much and therefore it had better throttle response. I trigger it using the points and have not replaced the points in 10 years. Prior to that, I was lucky to get 3 to 5000 miles out of a set of points.
DougComment
Comment