Section 4-General Regulations 8:4

[BblockAbody]

Master Cutoff, 2008 NHRA Rulebook. :read2:

I would like some ideas about how you guys handled this Rule.

I'm thinking the easiest thing to do is route power to the coil from the battery side of the switch, this should cut power to the coil when the switch is in the off position. Due to my battery being in the trunk this will make the lead for the coil pretty long and I'm a little worried about the amount of voltage drop at the coil.

some other ideas that have been mentioned was a diode somewhere in the alternator circuit I'm not an electrical genius so this sounds more complicated.

Or routing alternator output back to the battery side of the master cutoff switch, heavier gauge wire needed and an increased risk of a short large enough to start a fire.

Our first Test 'N Tune is Sunday so any help would be appreciated. :clock:

 

[68gts340]

I use a #4 welding cable for the charging wire, it has very thick covering so it wont short out or rub through easily, and it will not loose voltage going to the trunk. I put the cut off switch in the battery pos . feed line. the charging lead direct to battery pos. terminal. I also used a heavy welding cable for the pos, feed line.. ( size "00") be sure to solder the connectors to the cable....hope this helps.....

added thought,,,,, at the firewall i used a bulkhead connnector to bring power into the fuse block , every thing pulls power from there....

 

[bOb shingler]

purchase a continuous duty solenoid and wire it into the feed wire from the alternator and trip it from your battery cable going to the starter. this way when the cutoff switch is in the off position the alternator can't feed the ignition or anything else.

 

[BblockAbody]

Thanks for the great ideas, I think I'll go with bOb's idea it sound cost effective and not to difficult.

btw, I didn't take the car to the Test N Tune but with 2 more weeks until the first race I should be able to get all the little details sorted out. :cheers: