Not sure whats going on.

[grapro]

I have my car running again after changing out my latest new motor which only made 6 passes before my oil filter collapsed and starved the engine, not nice. But I seem to have a different problem with my new set up. When i apply the transbrake it seems to starve some power from the MSD box and it takes a second before the motor comes up to speed but only a short sec. I have tried  this without using the trans brake and there is no hesitation at all. My battery may have been a bit low but I've charged it since and have not tried it. Is it possible I was short of some voltage and it caused this or do I have to wire my brake directly into my battery as now it comes off the same main harness?

[Paul New]

Voltage drop what size of wire are you using for your main? Also an MSD requires 12-18 volts to operate lower voltage in means lower out. Pretty sure most people running an MSD ignition switches to a 16volt battery or put an alternator on their cars

[dreracecar]

Very common problem while running a MSD ign over a magneto. Door cars get away with it because they can run an alt to cover starting draw and fuel pumps and still provide for the MSD while on the brake. Its imperitive that one keeps the battery fully charged at all times, but can bite you in the later rounds if they start "hot lapping" the cars and not enough time to charge the battery.

[JrFuel Hayden]

We use a light weight , one pound, 14 amp battery with our MSD mag , just for the transbrake and RacePak, and we don't need to charge the battery all week-end. We use two 12 volt light weight batteries [ 10 lbs] for our remote starter pack. BTW our RacePak always reads the voltage of the on board battery. If anyone wanted to mount the two light batteries in the car and remove 10 lbs of ballast, then you could not have to mess with remote starting or the motor killing after a burn-out.
Hayden Wheels, sells them.

Jon

[masracingtd1167]

Sounds like low voltage or a huge draw from the trans brake . You do need a good battery and charge it between rounds and you will be fine !

[dreracecar]

Or throw a magneto in it  and dont worry about it

[Van]

Don't throw a mag on it and don't worry about it. Mags die & their coils do to. In the last 4 years I've seen at least 8 times a blown car came to the start line at Bakersfield and The mag was dead. There is a video on the 6.0 Altered site showing a mag coil going up in flames recently. Point is nothing is going to be 100% reliable.  I run a MSD 10  (ancient)
we recently did 6 startups and 5 runs & charged the battery once. I start and run on one 12 volt Optima. Some day I might run a mag again but not to just- not worry about it.

[dreracecar]

20 years running and 1 coil,  20 years and 6 rounds won because the other guys ignition quit

[masracingtd1167]

I have my car running again after changing out my latest new motor which only made 6 passes before my oil filter collapsed and starved the engine, not nice. But I seem to have a different problem with my new set up. When i apply the transbrake it seems to starve some power from the MSD box and it takes a second before the motor comes up to speed but only a short sec. I have tried  this without using the trans brake and there is no hesitation at all. My battery may have been a bit low but I've charged it since and have not tried it. Is it possible I was short of some voltage and it caused this or do I have to wire my brake directly into my battery as now it comes off the same main harness?

   I just re read your post . With an MSD you should run a separate power wire to the box and a separate ground wire as well ! There seems to be a difference of opinion about what ignition to use but seeing that you have the MSD I would stick with it . I can't tell you witch one is better but I can say that the MSD that I use has worked very well ! 

[JrFuel Hayden]

Van,  what mags were your buddies running went they came to start and they were dead ?  Mags with points ? Spud makes some better points for those mags.

[Van]

Van,  what mags were your buddies running went they came to start and they were dead ?  Mags with points ? Spud makes some better points for those mags.

 Hi Jon
 All of the times I've seen a no fire was with the Funny cars at the March meet or the Saturday nite nitro. I know the Funny cars must run the points mags. None of those guys are buddies & I couldn't even name names, just what I've observed as it happened. Most everyone knows about the points mags killing the points & the smart guys have upgraded to the new system Spud now offers. To bad it took 35 years to see that fix come around. Mag guys are very defensive about their mags and love to say     THROW A MAG ON IT    most have one or two spares in the trailer *** except Bruse*** . I don't hate on mags, I just want to see real solid reasoning to put mags at the top of the ignition food chain, then we will all know that the high percentage of racers using battery systems are doing it all wrong.

[dreracecar]

The longer spark duration of the mag works better in an alc app. Would I run a mag with gas--NO--different spark required.

 I dont carry a spare because I know some racers that carry one and can always borrow one, How many racers carry a spare MSD box???
Main cause of mag breakdown stems from the coil wire going bad and it seems that racers often take that wire for granted.

[masracingtd1167]

The longer spark duration of the mag works better in an alc app. Would I run a mag with gas--NO--different spark required.

 I dont carry a spare because I know some racers that carry one and can always borrow one, How many racers carry a spare MSD box???
Main cause of mag breakdown stems from the coil wire going bad and it seems that racers often take that wire for granted.

       I can't tell you witch one is better or faster . I ran a Vertex for years and can say it never let me down ! when I built my current car I went to a 7al3 msd box because it had some nice features like a high rpm chip , a burn out chip and an rpm switch for my shifter ! I have sprayed it with a 300 shot of Nitrous and Alcohol and it has performed very well for me ! I do see the advantage of a mag when you are running huge amounts of fuel like a blown motor . i think an MSD puts out like 4 amps . What dose a good mag put out ? Bruce over here in Division 1 I would have a better chance of gettind an MSD box than a mag !

[dreracecar]

A fresh Vertex puts out 1.7 amps and a Mag III @ 3.5
West Coast rules for 7.0 , one is only allowed 1 high RPM over-rev chip, so those other features must be blanked and sealed.

Alc fires at different times during compression stroke as heat and cyl pressure builds. A cold engine it fires towards the top of the stroke and when warm and boost is present, where the mag is timed at, so the duration covers the range.  Gas fires off where to tell it to from the timing aspect so it requires a hot spark at that moment.

I am very simplistic in my approach to racing I only have 1 wire on my car and thats only for the mag ground, even then its only used for starting the engine. Running a battery, starter, ignition wireing loom and boxes,and battery shutoff,  increases the chances for something fail, I even won a major GoodGuys race because the battery kill switch on the other guys car failed and had no power to start the car---Single for the win!!!!!