I do work with an old setup, a boxer,23 years never torn down.
the greatest cleaner has been egr shut off.. cold air intake at all times (no heat rise).. coil upgrade, reonator scrapped forver, in place a custom chamber...and let the gas tank suck air in ..but do not leave it like that.
cruddy things will be flying out the back in no time flat. Did I say flat..