View Full Version : Spark / Nos

Paul Webster
09-22-2003, 02:17 AM
We've tested the current spark plug leads on our car and they measure 1900 ohms resistance, we then made up the a 3ft MSD lead and sure enough they measured 150ohms resistance.

We earthed out the spark plugs on the chassis and wound the engine over on the starter motor and there's no visable difference in spark.

Do you think it could be one of the following;

The MSD 7AL is not performing

The MSD HVH pro race coil is not performing

Dizzy is a points type.

The main problem we have is when we hit the secound stage not alot happens in fact no improvement at all;

Could we be blowing the spark out??

or is the battery / alternator i not keeping up?

what amperage battery should we have??

what ameage alternator can you get away with??

496 BBC
1 x Fogger 300hp
1 x Big Shot Plate
1 x NOS Controller digital
1 X MSD 7al
1 x MSD HVH Coil
1 x Electric water pump
1 x electric fan (not running on the run)
1 x Mini torque starter
1 x BG King Enduro Pump
1 x Holley Blue Fuel Pump

1953 Ford Pop 8.64 @ 163 on Pump gas on Mickey Thomson Sportsman Pros
( Treads )

http://eurodragster.com/live/2003doorslamm...ian_jackson.htm (http://eurodragster.com/live/2003doorslammerinternationals/pictures/sunday/html/jeff_meads_v_ian_jackson.htm)

09-22-2003, 11:13 AM
If the spark is going out, you may want to reduce the plug gap, to see if this will help. The voltage requirement for the MSD Unit should be around 12 to 16 volts; this is where it will get the better spark energy. The amperage is 1 amp per 1000 RPM's so as long as it has an alternator that maintains voltage you should be fine. If the problem still persists it may be you are running to much cylinder pressure for the 7AL and you may have to upgrade to the Digital 7 Plus, this will have 40% more spark energy.