Discussion and questions related to the course Flex Fuel Tuning
what kind of spark plugdo you recommend for 4 cylinder engines when switching to E85?
My car is used on the drag strip and running 2,5 bar of boost.
I am not sure what to use. I heard of people talking about using "colder" spark plugs?
Anybody here with similar setup with any suggestions?
By reading the spark plug you will be able to ascertain if you need colder plugs we have a webinar to help with this https://www.hpacademy.com/previous-webinars/127-spark-plugs-essential-knowledge/
Good question. I would normally use one grade colder/harder spark plug as a matter of course, even two may be needed for some applications - I don't recall using more than that, but I see Andre mentions up to 4 heat ranges - if it fouls (builds up deposits) I would expect to go back one grade. One thing to be careful off, some brands use higher numbers for colder plugs, other brands use lower numbers - getting them wrong has destroyed more than one engine.
It is much better to start too cold because a hot plug can cause pre-ignition and other nasties.
There is a lot of information on the interweb about the spark plug design and selection, well worth a few hours reading up on it.