what is a better choice for a revlimiter the pcm or and ignition box? why

 

It's my opinion that an ignition box makes a better "rev limiter" due to the fact that it drops spark rather than fuel.

 

Ignition box with rev limit is much better than the stock limiter.
Just have your stock limiter raised to 7k or so and then use the limiter in the ignition box you choose.
For example, my stock limiter is set to 6800 and my Accel 300+ is set at 6250.

 

What's wrong with the PCM's method of cutting the fuel? Contrary to popular opinion, it doesn't "lean out" the engine as it is cutting fuel completely for any particular cylinder for that combustion cycle. In other words, NO fuel is injected durring that cycle, and thus the cylinder should actually cool down, if anything. Killing the ignition randomly as most ign boxes do seems, to me at least, alot less elegant and certainly not as effecient.

 

Is there a way to blow passed your rev limiter?

 

the rev limiter will save your engine from over rev in a case of acceleration but the engine can still see an over rev condition if too low a gear is engaged.
the ignition will cut out but the motor can still over rev.

I have hit the factory rev limiter before I had the PCM calibrated and I installed the ignition box and I thought I had done major damage its such a nasty way to limit in my opinion. The ignition cutout is much less violent.
Its just a stutter instead of the harsh jerking for and aft I expeirenced with the factory limiter.

 

For that reason, fuel cut makes for a cleaner and safer form of rpm control.
I don't see anything wrong with fuel cut. Even if the fuel cut was not as quick/clean cutoff as it is, and did a smooth lean out till the engine died, it wouldn't hurt the engine. Contrary to popular opinion, an extremely lean mixture runs cooler, with cooler exhaust temps, rather than hotter.