A friend drilled holes in his Y pipe pre cat to increase mpg due to fuel prices.

Opinions ?

 

is the V36 cat setup different than the V35? my cats are in front of the y-pipe. i have leaky y-pipe gaskets that i need to fix and they make the car sound like crap. i don't think drilling holes in the y-pipe will increase mpg and i think it will make it sound bad. all the old mpg threads i've read seem to come to the same conclusion that even driving these cars like a granny can only get you so far and basically if you're worried about mileage you're in the wrong car.

 

Drilling out the cats is not going to affect his mpg, and unless he actually removed all the cat media it's probably going to rattle around and get wedged into place to actually restrict airflow. All it will do is throw catalytic efficiency codes which will make the vehicle run worse.

If he drilled holes in the y-pipe that's just an exhaust leak, it will sound bad and still not affect his mpg.

Like the previous post, there's not much you can do for efficiency without actually getting a tune.

Try to find an old Geo Metro, those things got like 35 city, 45 highway and that was 30 YEARS AGO. Blame the EPA for our bad mileage, Suzuki still makes the car (they made the Geo Metro) and sell it overseas, a friend of mine has one in the Netherlands and gets almost 80mpg. He averages over 60mph combined city/highway!

Could you even imagine that in the USA, a subcompact shitbox gas hybrid car that can get 80mpg on the highway... but once they strap on all the emissions requirements stuff mandated by the EPA that same car would get just under 50mpg.

A Prius, any generation, is also a good choice. Same with the old first gen Honda Insight but those things are crazy expensive now because they still get 50-60mpg.