[86MLR]

Punch out the cat in the OEM header, punch out the cat in the OEM front pipe, full OEM exhaust, not loud, flows well up to 200hpatw.

Or

Because UEL headers are loud.

Catless UEL header, 2.5" overpipe, decat full OEM 2.25" exhaust, then a Ecutek tune. (My current set up after getting sick of noise for no gain).

Cat back is wasting money NA, the 2.25" front pipe back flows well up to around 200 hpatw.

You don't need to sleeve the cat.

Don't believe, do the math, do a run.

Profit

Cool story bro: I know a supercharged 86 that got around 270hpatw (200kwatw) with a full decat header and stock decat exhaust and some hours on a Ecutek. Apples and oranges yes, but still. With a full exhaust it made 15kw more after some tinkering.

After the header and decat the rest is 100% in the tune.

IF, you race for sheep stations and are looking for a tenths a lap then more though into design would be of advantage.

If your a punter driving to work or through some twisties on the weekend, you ain't gonna notice jack squat, yes yes yes, unless your awesome......

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