You probably don't have to touch the intake manifold unless you're going boosted or a serious high compression build.
1/4 times shouldn't ever be a goal for a DD Focus. It's a small, light FWD car that with the right mods can be a great car to take out to a windy road on the weekend.
"My yellow, in this case, is not so mellow" -Jimi Hendrix
Extremely helpful people
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