ttotired - 2015-12-17 7:04 PM

For salt racing, dont you want to get it to rev like crazy?

Things like electronic ignition and heavy valve springs and a light flywheel with a manual box would be the important (building blocks) first?

I dont think we really have much like that here, so not really sure

ttotired - 2015-12-17 9:10 PM

The problem with CD ignition of that type is that although the switching of the coil is done electronically (which is good) it is still triggered by the points

The problem with that is contact float and bounce which happens at high rpm

Basically, the cam in the distributor at high rpm works like a ski ramp which alters the timing and reduces dwell time, thats where full electronic ignition comes in

Because there is no mechanical contact in a fully electronic system (be it hall effect or luminition) its rpm tolerance is almost limitless

It gives the cleanest spark possible for a distributor based ignition system, only way to get better is to go to a computer controlled ignition and individual coils mounted in the spark plugs as its done on the latest fuel injected engines

Not impossible to do on any engine, but rather impracticable for the slight gains you would get on an engine not designed or built to do F1 engine rpm

Pretty much the same as for indexing the spark plugs, gains are possible, but not huge

Weight savings will help a lot more

Personally though, I would forget the CD ignition, it was a great improvement as a budget way to make your points last until the rubbing block wore away to not much, but as full electronic ignition systems became more main stream and cheaper, the CDI systems fell out of favour if full electronics could be fitted or retro fitted (like a pertronics type kit)

One thing that is a positive for the CDI system is the adjusability of the dwell time thats factory set in all full electronic systems (except for computerized electronic systems that can be tuned using a computer)

Only way to adjust those is by varying the size of the holes in the chopper plate for luminition or the gaps in the hall effect

The things that will limit rpms are contact bounce from the points, valve float and fuel supply and exhaust including cylinder scavenging and combustion chamber dilution

I am probably getting a little carried away here with full race engine considerations that might not be in your plans, but getting a car up to a certain speed is easy, to get it to go that bit faster after that is where the silly stuff (like indexing plugs) comes into it

Bad idea showing me go fast stuff