Autosport Labs

I am preparing the car for a 12 hour enduro and anything that can go wrong is likely to go wrong.

Has anyone thought out the details of running 2 units parallel and being able to switch back and forth from a simple switch?
Thanks

Anthony

I'd just keep a spare coil pack, EDIS and crank sensor in the paddock. Provided the wiring joints are all good you'll not have any issues.

The bloke who i bought my megajolt from had had it as a spare as he raced. However he just had it, with his map on it, in a box in the paddock.
- I imagine he had a spare coil pack, edis unit, cps and tps too. BUt the most sensable thing to do to me would just to have a spare, rather than a second that you can hot switch to. Becuase otherwise you switch is almost as likey to fail as anything else.

Dhutch wrote:Becuase otherwise you switch is almost as likey to fail as anything else.

Insightful point!

Anthony,
The components Gilesy998 listed will all stop your car if they fail. The MJLJ will only put you into limp home mode, so the listed parts would need to be on board for a quick trackside fix. The Megajolt could be left in the paddockand you could drive to the pits and replace it.

spitfire50 wrote:Anthony,
The components Gilesy998 listed will all stop your car if they fail. The MJLJ will only put you into limp home mode, ...

If the megajolt unit fails, it's the EDIS unit that goes into limp home mode (10 degrees static advance).

If anything, on the car you would want switchable coilpacks and EDIS modules rather than Megajolt. As stated, if the coilpack or EDIS module fails, you stop.
Atleast if the Megajolt fails you can still race with the EDIS at 10 degrees static.

Jason.

On a racer, even an endurance racer where reliability is more important than outright speed I'd certainly not waste weight and complexity on the car to run dual ignition systems as the reality is that they just don't fail.

EDIS modules, particularly the EDIS-4 modules are indistructable, 4-post coils don't tend to fail either but they are both cheap enough to be worth having one in the spares kit in the paddock for diagnostic purposes if nothing else. In enduro racing you are far more likely to foul your spark plugs or melt wiring/plug leads than anything else so keep spares of those in the spares kit too.

"On a racer, even an endurance racer where reliability is more important than outright speed I'd certainly not waste weight and complexity on the car to run dual ignition systems as the reality is that they just don't fail. "

The reality is that they do fail. In a hi vibration environment (where we have mounted the MJLJ on anti-vib stand-offs) we seem to have minor issues about every 12 hours of track time. The culprit previously has been a processor which likes to separate itself from the board. We have now potted the component with some silicone and will see how we are doing....we are 16 hours into racing for the year so far.

So yes they do fail and a swap of the unit (we already have a spare) takes 10 minutes. Would be better to have it switched IMO.

Anthony

Anthony,

I think it would be preferential to fix the vibration-induced reliability issue rather than put a band aid on the problem with a dual redundant switch. To that point, who's to say the backup unit didn't have it's processor rattled out of it's socket as well?

A switch to a V4 unit with it's surface mount components and using soldered, un-socketed chips will go a long way towards improving vibration resistance. If this *somehow* proves to not offer very long term durability then one can look into dual-redundant systems. Then, of course, you have the problem of the mechanical switch being a single point of failure. sigh!

Your potting will likely help as well. I'd like to hear how it fares after your race.