etherhuffer

Well, consider this: Blow an ignitor on a trip and if you don't have a spare one, walk down to the dealer and cough up 175 bucks. With the MSD, you have no leading ignitor. If your MSD craps out, they have one in every local store. Even Aw Schucks in Seattle stocks them. And they are less than a new iginitor. Not everyone on the board can have a boneyard nearby or spare ignitors. Considering that poor spark will kill runability in a minute, I prefer the MSD. You can live with a small vacuum leak or fuel mix problem, but not poor spark.

peejay

You mean you don't carry spares in the car?

Jeff20B

iTrader: (13)

I carry a spare coil-to-cap wire, in the unlikely event of a blown ignitor. It costs me nothing

mar3

iTrader: (8)

There's a reason ignitors are the first thing that disappears off any 1stgen that hits the junkyards...and it ain't cause they're dead reliable...

peejay

lol

I'm glad the junk 12A I got came with its distributor.... got two good ignitors

PaulFitzwarryne

The theory is that on a NA engine with a carb and no oxygen sensor as with EFI, a MSD set-up will give a more consistent and stronger spark. This overcomes problems with the a/f ratio. particularily when its too rich.

The set-up as the result of a better spark is reported to give slightly better fuel economy, smoother running, and easier cold weather starting. Some drivers claim a 2-3% increase in power.

The reality is that the benefits for a well set-up street engine are minimal. However, a MSD sometimes helps when for some reason the engine is slightly off tune. It seems to be more forgiving to minor problems with jetting, wires and plugs.

For a relatively stock engine there are far cheaper ways of getting performance. In a high perfprmance situation it may be worth while installing a MSD to get that last bit of performance.

The improvement will always be small so in the end it becomes a matter of subjective perception. It gives a more classier look to your engine bay. At least adding a MSD will have no adverse impact except on your pocket.

peejay

This may be where many people report more power with the MSD.

The stock carb tune is not optimal for power. It's too lean down low for best power, and it gets really rich at the high end because of the undersized carb.

If you take the time to tune it well, meaning dick around with airbleeds and jets until you're blue in the face, or scrap it all and get a decent sized carb that is fully adjustable (ahem Yaw-modded Nikki or a nice Weber) then the stock ignition system is pretty good.

I should add that my best times with White Trash were with the fuel pressure cranked up so high and the idle mix so rich that the plugs would have to be sprayed with carb cleaner and brushed clean after each run. Just that much carbon! That's why I feel there was MUCH more power lockied away with carb tuning, since I was too stubborn/cheap to rejet the carb (hey they don't call me Shallow Pockets for nothing!)

Without the MSD that kind of tuning would have been QUITE detrimental. But with it... I just kept watching the ETs drop and MPH go up as I kept cranking up the fuel pressure, until I was bypassing the regulator entirely. The idle richness was for throttle response - just not enough accelerator pump. (i later found that the linkage was extremely worn, causing the throttle response problems)

Now, of course, I know better

mar3

iTrader: (8)

I gots 5 spares...