I have an Ariel Atom with the Ecotec supercharged engine and I am finally getting it tuned.
The tune that came from the manufacturer is not the greatest, plus I've changed the entire exhaust so I should re-tune it.
I have a little problem with the idle.
When I approach a stop the engine rpm's do not just gradually drop down to a 900-1000 rpm idle, but instead the rpm's drop down to say 200-300 rpm's and and then fluctuate up and down and eventually settle around 100rpm, but sometimes the engine stalls.
Does anyone know what the problem might be?

Secondly, before I get the engine tuned I was thinking about changing the spark plugs and was wondering if I should just replace them with OEM plugs or if there is a better choice.
cheers

 

Check for vac leaks, this can hurt your idle

 

Stock plugs are fine. Might try a smaller gap tho

 

Dont forget to check the throttle body for tons of gunk as well. Clean that bish!

 

You have an Ariel Atom??? That's saweeeeet! That thing is gonna haul ass! Vid of you ripping on it when it's done or ban lol.

 

check for vac leaks, if not look at your idle timing table(s) they might be all sorts of ugly.