WhiteFormula98

iTrader: (10)

I know that a open cutout is worse mpg, but how much better do you think a bullet turndown on a y pipe mpg would get compared to cutout?

orangeapeel

iTrader: (18)

Why are you worried about gas mileage and power output at the same time? You should know that they don't work together. You get one or the other.

00cls1camaross

iTrader: (10)

dump, lighter and make more Hp than a y pipe with cutout

RoWDyWS6

i aint a fan of dumps.. i do like tru-duals running all the way thru the tips tho!

i vote for open cutout!

99z28monster

iTrader: (3)

go dumps with a good muffler

ChocoTaco369

An open cutout only hurts your fuel economy on a stock tune because it throws off the A/F ratio. If you get your car tuned with the cutout open, you'll gain mileage by making the exhaust work more efficiently.

IMO, exhaust is a sound mod first, performance mod second. Do whatever you think sounds better, then get your car tuned to optimize the effects.

Raise

iTrader: (31)

+1

NHRAMAN

iTrader: (1)

that is crazy..a cutout under rear seat WILL NOT AFFECT A/F RATIO..PERIOD.

Unleash

I have used a cutout and a capped SLP 2OTL and didn't notice any mileage difference with either. Basically it sucked either way with a cam.

ChocoTaco369

Yes it will. A cutout will affect the A/F ratio in the exact same way a catback or a set of longtube headers will affect the A/F ratio. Are you denying that adding a catback or headers affects the A/F ratio? Because if you agree that one of them affects the A/F ratio, you must also agree a cutout will.

My cutout open dropped my fuel economy by 1 mpg. Explain to me how a more efficient exhaust setup will drop fuel economy? It's because it threw the tune off even more - rich down low, lean up top. Same as a set of headers or a catback with a freer flowing muffler than stock.