straight pipe

[Zetec_contour]

does anyone know how bad my gas mileage would be if I were to straight pipe my 'tour? Cause I think it would sound really cool!! LOL

 

[bagged]

it doesnt sound cool, it sounds raspy as hell and loud like a honda. dont do it IMHO

 

[ronssvt]

I don't think its gonna make your gas milage worse, unless you drive more agressive after the exhaust is put on.

 

[greasemonkey1489]

Yes, it would affect your gas mileage. There would be little to no backpressure in the exhaust system which would cause the engine to suck in more fresh air, MAF would sense that and increase fuel delivery. Especially if you remove the CAT

 

[ronssvt]

got any proof of that?

 

[Dyoel182]

Yes, it would affect your gas mileage. There would be little to no backpressure in the exhaust system which would cause the engine to suck in more fresh air, MAF would sense that and increase fuel delivery. Especially if you remove the CAT

Thats an old myth.

 

[beyondloadedSE]

Yes, it would affect your gas mileage. There would be little to no backpressure in the exhaust system which would cause the engine to suck in more fresh air, MAF would sense that and increase fuel delivery. Especially if you remove the CAT

Not sure if your saying this is good or bad. The increase in air would be very minor. If anything, it will free up a little bit of hp, make the engine more efficient and increase gas mileage. On the other hand, its going to sound terrible. Myself and many others have heard many Contour's like this and its not pretty.

 

[waves360]

wont it make your gas better

 

[greasemonkey1489]

I believe it will burn more fuel. I straight-piped my jeep and went from 14mpg average to 12.5mpg average. Same driving habits. It was a little louder and had a slight increase in performance but gas mileage was significantly affected.

 

[Harrry]

I believe it will burn more fuel. I straight-piped my jeep and went from 14mpg average to 12.5mpg average. Same driving habits. It was a little louder and had a slight increase in performance but gas mileage was significantly affected.

Yeah i guess an inline 6 jeep had the same engine and exhaust as our contors. :crazy:

 

[amc49]

Actually it shouldn't be an "old myth". When back pressure is dropped, motor WILL flow more air, leading to more fuel; however, all things being equal, the extra power will then allow throttle to be closed a little more, which may INCREASE mileage. I don't hold with a lot of that "you gotta have some back pressure" stuff anyway. There are some quirky engines out there that in odd cases may need it, but any thing I ever worked on HATED back pressure. I have worked on a lot of street hotrod engines and if there's any one rule I've seen it's that the less pipe you have on a motor the harder it will run! When we used to build 395 inch American Motors engines for the street (typical 1/4 mile 10.70-10.80 @ 130 mph THROUGH THE MUFFLERS) we only used short header mufflers, these systems had no pressure WHATSOEVER, in fact when it worked right there was a VACUUM in the exhaust, that's proof the header is working correctly.

 

[beyondloadedSE]

So all of those that are saying it will decrease mpg, you would also agree that adding headers, catback, intake components, etc will decrease fuel economy? These too make the engine breathe more freely. Something doesn't add up.

 

[Dyoel182]

I believe it will burn more fuel. I straight-piped my jeep and went from 14mpg average to 12.5mpg average. Same driving habits. It was a little louder and had a slight increase in performance but gas mileage was significantly affected.

You say same driving habits but the science behind it says it wont burt more gas all by itself. Either you're taking a different route under different conditions or you were getting on the gas a little more than you thought you were.

 

[waves360]

wait i thought the better the car breathes the less restricted it is so its less stress on the motor which leads to better gas mileage more stress equals more the engine works which mean more gas wasted

 

[Dyoel182]

wait i thought the better the car breathes the less restricted it is so its less stress on the motor which leads to better gas mileage more stress equals more the engine works which mean more gas wasted

Thats the scientific theory anyway.

 

[Harrry]

wait i thought the better the car breathes the less restricted it is so its less stress on the motor which leads to better gas mileage more stress equals more the engine works which mean more gas wasted

Less work..yes but what we want to accomplished is more hp/tq. That way more power is created and less gas needs to be used to achieve the MPH we want.