MISFIRING OVER 4000 RPM? (SUPERCHARGER)
Turbo Mini Forums

I must say firstly though only under full beans, if i build the revs slowly its good to 6000, didnt try any further my ears started bleeding! what do u reckon? fuelling i.e not enough pressure or as i suspect timing to retarded? Or good old fashioned det? Im running 8 -10 psi 9.01 with standard metro dizzy. plug gaps ?

what sort of missfire, regular or irregular?

What AFR and advance at full throttle?

Standard Metro dizzy or Metro Turbo dizzy?

Could be a dodgey amplifier module.

Edited by Sprocket on 13th Dec, 2008.

Simple things first -try some harder (cooler running) plugs.

ive got 7s in at the mo . its an mg metro dizzy with module . i would say it feels like it is suddenly out of juice over 4000rpm, m probably way off but would a dodgy battery not help matters?

Sound very like the prob I had recently.New low resistance coil and hard plugs cured my problem,but it could be so many other things.Sorry I,m not more help.

No thats fine i appreciate any commments mate thanks :) it was pinking so i back off the dizzy a couple of degrees so im thinking it might be that. the head is at 26cc at mo so might take it out to maybe30cc and advance it a couple again?

You need to retard the ignition timing under boost.

I suggest that Megajolt would be the optimum solution.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

missfires under load !! are caused by AFR too LEAN

7s should be fine and if the fuelling is right 9psi at 9:1 shouldn't cause problems.

What is the rev counter doing when it starts missing? If it's flicking about its the module on the side of the dizzy. If not, my money is incorrect fuelling.

So a bit more profiling needed?

A trip back to the rr me thinks.

Fueling seems to be a problem in the supercharged ones. Get a lambda in the exhaust. Save your pistons and get it set up as well.
How long have you been running the charger? Is his a new problem?

new after the rr on tues just gone, it cuts out everytime i come up to lights and put the clutch down which makes me think vaacuum?

p.s fuelling was fine and everything then off the a road first set of lights and bluurghhh it dies.

take it back th the RR operator and tell him your Not happy let him sort it out

and dont part with any more cash to him

I was having this issue with mine. Every time you came to a junction it would cut out. I had fuel leaking out from t he weber in the end from a thread somewhere. Got it sorted and ran much better. But i always set it up on a rr and get it checked evey few months.

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Still a miss fire though, no?

Hi everyone, sorted it! Had a flash of inspiration i figured it could be not a good spark at the plugs,turns out the alternator wasnt charging!! changed it sorted!! Thanks for the help guys.

Pleased you got it sorted. Just proves that a good spark is very important with forced industion.Earlier in this thread I said I fixed my problem with a new coil and plugs so it was the same problem really.