Does installing a test pipe increase gas mileage.... i heard it throws extra fuel in the engine therefore hurting but i also heard it free's up power therefore gaining?? Can i get some insights on this? thanks

 

Any modifications that make the engine breath better will result in increased fuel consumption, in your case your reducing backpressure on the exhaust side which makes it more efficient for exhaust gases to escape the chamber leaving room for intake charge. Fuel trim will increase the injector on-time/duration because of high oxygen (lean condition) present in the exhaust sensed by the O2.


Modified by Flexmyrex at 3:35 PM 11/17/2007

 

it doesnt add fuel it frees up teh restriction of the cat.....

 

so in the long run will i be increasing gas mileage or decreasing gas mileage

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by S@nt0s &raquo;</TD></TR><TR><TD CLASS="quote">it doesnt add fuel it frees up teh restriction of the cat.....</TD></TR></TABLE>

You need to look at the big picture here. Where do you think the gained power comes from when removing the restriction? its not magically created. Simply put the decreased restriction causes more airflow/o2, results in increased fuel consumption produces a higher output. Engines need both to produce power, not only oxygen.

 

ok now i am offically going to bash every person that comes along with some post..

now if you wanna get technical we can.. the OP asked

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MADBADGER &raquo;</TD></TR><TR><TD CLASS="quote"> Does installing a test pipe increase gas mileage.... i heard it throws extra fuel in the engine therefore hurting but i also heard it free's up power therefore gaining?? Can i get some insights on this? thanks</TD></TR></TABLE>

no it will not increase gas mileage.....
learn your shiftpoints and to properly load your motor and you will see increased gas mileage...

and adding a test pipe does not ADD fuel... the "PURPOSE" of a testpipe is to "REDUCE RESTRICTION" caused by the cat....

now with the increased flow (less back pressure) which inturn scavages the exhaust better will allow more air into the CC thus increasing power.....

 

An internal combustion engine will not gain power by ONLY increasing the mass of the airflow without adding fuel. Testpipes increase torque as it helps the engine breath better, more specifically it increases the engines Volumetric Efficiency, there is a linear relationship between VE and torque. VE means nothing if you don't have fuel enrichment to compensate for the added airflow therefore no extra torque can be produced.
If you know of a 2 or 4 stroke engine that doesn't require fuel enrichment to make more power please let me know as I am tired of paying for high gas prices.

 

yes you are correct but as i said you dont need to add fuel to a motor that is ALREADY pig rich.... when the TP is added the flow in increased, more air in induced into the motor running a tad bit leaning making more power is that not correct?????

so again what the OP stated is NOT TRUE

 

word

 

holy ****.

ill let you guys handle this

 

Real life story...

I have a Berks and an HKS dual and I get around 27-30 miles per gallon. I really didn't notice much gas mileage difference than stock, but i did notice the increase in power. And damn, I love the sound. You could say my mileage suffered at first because of the way the exhaust sounded, I always had my foot in it. But driving conservative, I have hit 30 mpg on a tank of gas.

 

Fuel will be added via fuel trim in any pgm-fi under closed loop operation to compensate for the higher oxygen content in the exhaust, this is why we have o2 sensors. This means under low, part, and anything below 80% throttle fuel adjustments are made, in our case the amount of fuel going in is increased due to the higher VE. You have to remember that 85% of our daily driving occurs in closed loop operation so overall we are using up more fuel. As you stated above, its true the leaner condition does occur but the only time the mixture gets a chance to get leaner is at WOT (80%+ throttle) under open loop conditions where the o2 sensor is completely ignored and injector on-time is directly from fuel maps. Santos either way this is a fun converstation. Time to get back to work

 

Flex,
i know what you are talking about unlike most in here... but do you think the OP has any idea? NO!
there for i was keeping it simple when asked does adding a TP add fuel and give better gas mileage etc.....

but you wanna get all technical about it. i know the workings of a motor etc so no need to bring it to me. im still saying that the same thing to the question he/she ask.. and no the TP does not add fuel.
now there are other added factors that the TP causes with the increase flow... now there is where we will get technical with open/closed loop etc...

 

using a "test pipe" replaces the cat which makes the exhaust spit out fuel instead of recycle it with the back-pressure you lose gas milage

 

your car will be louder too depending on what kind of canister you have on. i have an apexi n1. that thing does not sound like an s2k anymore. its a vtec screamer. i want to do a db rating on it. haha. my engine check light also came on bc the reading the engine check light reader said catalystic converter missing or something like that. i forgot. and my srs bc of my wheel. no big deal. i just have these uneccessary lights on that doesn't make my gauge cluster look clean. o well. cry me a river. haha.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Y0N1P8T5R1F5A4T &raquo;</TD></TR><TR><TD CLASS="quote">your car will be louder too depending on what kind of canister you have on. i have an apexi n1. that thing does not sound like an s2k anymore. its a vtec screamer. i want to do a db rating on it. haha. my engine check light also came on bc the reading the engine check light reader said catalystic converter missing or something like that. i forgot. and my srs bc of my wheel. no big deal. i just have these uneccessary lights on that doesn't make my gauge cluster look clean. o well. cry me a river. haha.</TD></TR></TABLE>

coherent sentences please. we don't speak moronic here.


You have a CEL because no anti-fouler plug to fool your ECU.

 

My gas milage sucks.

Test pipe will only increase hp. If you worried about loosing/gaining gas milage then your into the wrong hobby. Everything you do to a car will make you gain and lose something.

 

I had a wideband O2 on my S2K and when I put on the test pipe it became more lean.
It was at about an A/F ratio of 11-12.5 and then with the test pipe it became 12.8-14.5.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Francesco &raquo;</TD></TR><TR><TD CLASS="quote">If you worried about loosing/gaining gas milage then your into the wrong hobby. Everything you do to a car will make you gain and lose something.</TD></TR></TABLE>

Like my manhood.