In essence hitting a conventional rev limiter is also bad as it momentarily leans the engine. The BeeR has advantages and dis-advantages, the fact that it's two stage so you can set two limiters (one when handbrake is engaged) means you can use it for a very basic launch control, set the BeeR to say 4,000RPM e.g. , disengage handbrake and off you go, not forgetting you could just do this with your right foot.
On a worn out CT9 they won't do much good, bigger or new turbos can take more of a pounding but most CT9's will be worn if they haven't been rebuilt considering some are over 15 years old. I have used one but I don't feel the need anymore a) as we have launch control and b) she's pops and
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