Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) What Did You Do To Your Morgan Today?

Prepared for my upcoming rolling road session with a revised two stage rev limiter strategy.



Newman quote their Duratec Phase 2 cams as making peak power at 7,250rpm, I'm actually targeting a shade over at 7,300rpm where Caterham quote peak power arrives on their similar 360 spec Duratec, the 420 model lifts this to 7,600, but I'm looking to keep Monty safely under 7,500rpm given he still runs standard rods and I'd like to keep them where they belong....

I.E, inside Monty's block


IGNITION SOFT CUT

Basically cylinder pressures are being progressively reduced by pulling 0.5 degrees of timing for every 10 rpm added starting from 7,300rpm, which is 150rpm below my outright soft rev limiter target of 7,450rpm where a maximum of 7.5 degrees will be removed from the 100kPa column in my ignition table and at that engine speed.


HARD FUEL CUT

In addition to the ignition basted strategy and for complete safety I've also implemented a hard rev limiter strategy that switches off my Bosch 440cc Green Giant injectors completely cutting all fuel to the engine at 7,460rpm and assuming a MAP reading of 100 kPa or above is met, which clearly it will be!


WHAT REALLY HAPPENS?

To help demonstrate what the two stage strategy delivers I created the following table in Excel.



I'll be encouraging the dyno operator to shoot for 7,500rpm but letting my EMU Black work it's magic to stop him having any chance of ever exceeding this maximum engine speed.


WHAT ELSE?

Obviously I continue to run my existing knock and IAT ignition correction stratergies.



These will provide an additional layer of engine protection on the day.... in theory!