Hi there guys, want some advice. Am running a 5.0 V8 on petrol only with an electronic dizzy it also has an RPI Power amp. Really fancy eventually switching to Megajolt the trigger wheel system like the idea of mapping etc am running on an edelbrock carb. Will I notice the difference is it worth it? Has anybody got any experience with it?? Cant help thinking that the dizzy is fundamentally limited and cant compete, or am I wrong is running really well at the moment dialled in with as much advance as I can without upsetting idle. Also what is the exact function of the RPI power amp (acquired it from a friend) how do I know if it is working??? Many thanks Guys
Megajolt question - Any experience
- Thread starter DaviesDJ
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Diesel Do
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No idea about megajolt!
The RPI power amp is an ignition amplifier. Aimed at replacing the black module on the side of the later dizzys. Ideally it's triggered by the sensor from the electronic ignition but I believe it can be switched by points! Kinda defeats the object tho
it has nothing to do with timing or advance/retard that's all still down to the dizzy vac system and bob weights! It amplifies the switch signal from the coil and keeps the coil charge time constant thru the rev range whereas with points the coil charge time reduces with revs so you get a weaker spark higher up the rev range!
So, your spark is more controlled and stronger you can very slightly increase your plug gaps to get a bigger spark but you need to use high quality leads. Ultimately it's limited by the distributor.
Hope that helps a bit
The RPI power amp is an ignition amplifier. Aimed at replacing the black module on the side of the later dizzys. Ideally it's triggered by the sensor from the electronic ignition but I believe it can be switched by points! Kinda defeats the object tho
it has nothing to do with timing or advance/retard that's all still down to the dizzy vac system and bob weights! It amplifies the switch signal from the coil and keeps the coil charge time constant thru the rev range whereas with points the coil charge time reduces with revs so you get a weaker spark higher up the rev range! So, your spark is more controlled and stronger you can very slightly increase your plug gaps to get a bigger spark but you need to use high quality leads. Ultimately it's limited by the distributor.
Hope that helps a bit
Diesel Do
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- Nottingham
Usually if they fail you have no spark so it stops! Sometimes the amplifier stops amplifying so you get a real weak spark which will generally stop them running but you do appear to have a spark so it can confuse you!!! Magnacor competition leads are recommended by RPI.
minimole23
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I run megajolt on a high spec 1380 mini engine. The principle should be the same however, and it has made it much pokier mid range, compared to the distributor before it and enables you to dial in exactly the right amount of advance for a given load.
Ultimately mine didn't make more top end power but it does feel more lively throughout the rev range, which is the main benefit of this.
Also you have various other features that can be added like rev limiters and all sort of other stuff if you feel the need to keep tinkering.
At the end of the day there's nothing wrong with a distributor, but you could spend ages and plenty of money getting it curved to suit the engine whereas with megajolt changes are easy and easily reversible.
Ultimately mine didn't make more top end power but it does feel more lively throughout the rev range, which is the main benefit of this.
Also you have various other features that can be added like rev limiters and all sort of other stuff if you feel the need to keep tinkering.
At the end of the day there's nothing wrong with a distributor, but you could spend ages and plenty of money getting it curved to suit the engine whereas with megajolt changes are easy and easily reversible.
you can still run MS with ignition only AFAIK
