VB921 performance?

[John L.]

I couldn't find anything on a search, but I was wondering just how capable is the VB921 as a coil driver, certainly it will work good for most people, but how does it stack up against factory ignition modules and even aftermarket modules, as far as output. I realize it's limited to 7 amps, which is why I want to know how good it is for high horsepower applications, especially very high boost turbocharged engines where spark must be very powerful to prevent misfires.

Thank you,
John Lewis

[GeorgeGt]

if u really gonna exeed 7amps , then u could use two in parallel , boths should have 330ohms on input and 0.05 ohms resistors between ground and pin3.

[John L.]

Well, I know that you can use them together, but I'm wondering what does it take for an aftermarket ignition box to produce such a powerful spark and how does the VB921 compare? The Ford TFI system is supposedly very powerful but I wonder how the VB921 compares to it as well. The problem isn't running the coil in general, it's supplying the coil with more energy so that the engine doesn't miss under elevated boost levels and under lean mixtures at cruise.

I guess the difference is still that most ignition boxes are capacitive discharge and the Ford TFI and the VB921 are inductive systems?

[jsmcortina]

With an inductive spark system the only question is whether the VB921 or spark box is able to fully charge the coil. If the coil needs more than 7A to reach saturation then you may have a problem. CD systems are a different game and use the energy stored in the capacitor inside the box. The ignition coil just becomes a transformer.

James

[John L.]

Alright, that clears things up a little I think.