I am installing a Msd Blaster 2F coil on a '78 F150 Custom L6 300 with the Durospark 2 ignition system.
I have read that the plug gap can be opened up to .50 from .44??
But just about every thread I have read also had a Msd 6,6a, or some equivalent ignition control box. I am just installing a coil at this point.
I in advance, appreciate all input. Thanks JoeWelds.

 

Go ahead and go 50 those basic spark boxes don't create a stronger spark. Only a good coil and wires in junction with a DS2 do that. IMO it doesn't get much better without spending huge bucks.

What condition are your wires in and what are they?

Did you just buy the coil? Have you installed it yet?
I ask cause for the money there are better coils if you are ok not using a canister type coil.

 

Wires are accel 8 mm spiral. They are less than a year and in good shape. When I got them I didn't know I should go 8.5 mm.
I did just buy the coil. It was a 8202 blaster 2. I was too sure on the wires, as the coil has a +&- stock coil only had batt on one terminal. So I called Msd and asked which was which. They told me there was a Blaster 2F #8205 that I could still use the Ford ds2 cap thing. So I ordered thru Oreallys. Supposed to be in today.
What are some other ones you were thinking of? I would just like a good one and price is always a factor. The only reason I got the first one was it was on sale for $39

 

Please no more accel wires, they blow as with most accel products, next time either the MSD 8.5 or my fav the taylor 8.2 thundervolts. Both are only 50 ohms per foot where the accels are somewhere in the thousands.

99% of aftermarket coils will have a + and - marked threaded post. On the duraspark the red wire goes to + and the green to -.

So you got a MSD 8205? That coil will of course work just fine and install super easy. It's a 45,000 volt coil which is as high as canister style coils go, but most aftermarket canister style coils are 45,000 volts so nothing really special.

An E-core style however can do better. I use this 60,000 Volt Canister Coils 60,000 volts and a decent price. I think I paid about $65 for my last one. Two downsides for you though. You'll have to make a way to mount it and it's a male plug as your coil wire is likely for a female coil plug.

My suggestion is wait until your doing a complete tune up, $39 for a blaster isn't that unusual of a deal that you have to get it now. Then you can replace the wires, coil, cap, plugs etc all at the same time and set it all up together.

Edit, on my 460 I use the pertonix coil, taylor wires, MSD cap, and normal autolite plugs gapped at .65 but could certainly go bigger/side gap if I was less lazy and willing to change my plugs more often.

 

Whoa that is pretty tough looking. 60,000 volts is just under a third more power. Even if it was mounted on the firewall it'd only be an other 50 ohms more R. Hmmm

 

Yep, go ahead and gap your plugs to .050 (not .50).

Just make sure your block ground/battery negative ground is as near perfect as you can get it too.
A poor block ground can/may cause spark jump in weird places and you'll also get the "corona effect" at the spark plug boots.

Bob

 

Thanks TB, I have gone thru and made sure most of my important grounds are in good shape. As soon as I got my truck from my brother it had electrical issues.
There is more work to do but most major grounds have been redone.

 

Wait till you get new plugs, the ground tang on plugs weakens over time and regapping only makes it worse, when the tang breaks off it eats pistons. The parts motor I just bought has 4 pistons that look like chewed up and spit out hamburger due to the previous owner being cheap.

Plugs are a LOT cheaper than a rebiuld!

According to "Performance Ignition Systems" Book written by the man that created Jacobs Ignitions

Conditions Gap Change Expected benifit

1 Tune up often (+) .006 4% mileage gain

2 Only tune when (-) .004 Increase between tunes
runs poor

3 Install Aftermarket (+) .025 Power 8-12% +
ignition box Mileage 11-23% +
Double to triple between tunes
Engine life 33-38% +

4 Aftermarket wires (+) .006 4% mileage +
2% power +

5 Drive easy/light throttle (+) .010 6% mileage +
5% power Loss
Tune more often

6 Aftermarket Coil (+) .007 5% mileage +
4-7000 more between tunes
3-7% Max Power +

7 Lead Foot Driver (-) .010 6% power + around 4K RPM
7% Loss Mileage -
25% decrease between tunes


This is a rough chart and I Summarized and changed wording from "Jacobs Products" to "Aftermarket"

I run a Jacobs Mileage Master box, Jacobs Ultra Coil (Variable Magnetic) , Taylor Wires, Autolite copper plugs and acording to everything on chart I could have ran .095 gap, I ran .080 gap and had no detonation and motor was VERY happy with Power and Mileage.

 

Theoretically you can just keep opening up the plug gap .005" at a time until it starts to miss at load then close it up .005".

And you can get a set of indexing washers so you've got all the plug gaps pointed down towards the piston. It makes a tiny difference, but a difference nonetheless.

 

I index so the gap opening is facing the intake charge, seems to have worked the best dynoing my Harley but that's a massively different combustion chamber design.

 

Wouldn't side gaping be better. Even tho you have to replace more often?

 

Very interesting thread.

I've been getting lazy with my engine. I have the Taylor wires, but one of the boots tore and I replaced it with --the ultimate crime--a j/y wire.

I need to go through it all with a good tune up. I have an msd 6a, with a ds2 dizzy recurved, a TFI coil.

 

So along the same lines, well a part of the ignition system.
Is recurving a dizzy or aftemarket the way to go?
Recurving, it is involved doesn't seem to be to daunting of a task.
Some aftermarket dizzy's get spendy. Compared to weights and springs.
Just a question.

 

All depends on many many factors, the curve you have, the one that is best, the wear on the dizzy you have, etc.

No real answer to the question until you know more.

 

I wouldn't bother recurving until you get the new motor done, as with the new intake/exhaust/carb setup the curve would need to be different anyway. Duraspark distributors are pretty good, msd uses the same magnetic reluctor design as the Duraspark just in a fancier housing, the bigger cap is a plus but your engine will probably never see the rpms that warrant the cost, is just get a Cap-A-Dap next tune up.