RickyG
Well-Known Member
reasoning?
future exhaust set up
- Thread starter RickyG
- Start date
reasoning?
mraw112
Well-Known Member
dont go 3 its just more weight and going to cost more. i would just go or 2.5 all the way back. just increase the pipe dia to meet the muffler.They have pipe expanders that can do that for you. they are free to rent at autozone. If you were in ga i have like 13ft of 2.5 pipe sitting in my attic id give for like 20$. also you never want "back pressure" for any setup, unless your trying to spool a turbo. You lose low end power from lower exhaust velocities. not "no back pressure"
RickyG
Well-Known Member
^^^^^^^^^^^^^ that sounds right to me. and for some reason i thought that you wanted some back pressure in your system but i guess not. haha. thanks for the info.
HondaLuver83
Well-Known Member
Please explain to me how back pressure helps a turbo spool. Not to sound like a jerk...lol
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are you kidding me?
you WANT back pressure for F/I set up? LOL
rule of thumb is this:
for F/I set up- you want free flowing exhaust, meaning, you DO NOT want back pressure.
for N/A set up- you DO want some back pressure.
no back pressure on N/A set up means, engine has to do more work to push exhaust gas out of exhaust valve, out to exhaust manifold (or header), to pipe, and finally out of tail pipe (muffler). yes, more engine work required to push those gas out means engine is not making as much power as it could.
simply put, it loses lower end power (i sense someone's post- "we dont even have low end tq to lose to being with har har har"
), and high-end will "seem" like you gained power.also, if your theory was correct, he should go with 3inch diameter....no? LOL
HondaLuver83
Well-Known Member
are you kidding me?
you WANT back pressure for F/I set up? LOL
rule of thumb is this:
for F/I set up- you want free flowing exhaust, meaning, you DO NOT want back pressure.
for N/A set up- you DO want some back pressure.
no back pressure on N/A set up means, engine has to do more work to push exhaust gas out of exhaust valve, out to exhaust manifold (or header), to pipe, and finally out of tail pipe (muffler). yes, more engine work required to push those gas out means engine is not making as much power as it could.
simply put, it loses lower end power (i sense someone's post- "we dont even have low end tq to lose to being with har har har"
also, if your theory was correct, he should go with 3inch diameter....no? LOL
Exactly the same understanding I have lol....If backpressure helps a turbo spool then next time I get to drive my fathers wrx I will stick a couple bananas in his exhaust pipe hahahahah
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mraw112
Well-Known Member
are you kidding me?
you WANT back pressure for F/I set up? LOL
rule of thumb is this:
for F/I set up- you want free flowing exhaust, meaning, you DO NOT want back pressure.
for N/A set up- you DO want some back pressure.
no back pressure on N/A set up means, engine has to do more work to push exhaust gas out of exhaust valve, out to exhaust manifold (or header), to pipe, and finally out of tail pipe (muffler). yes, more engine work required to push those gas out means engine is not making as much power as it could.
simply put, it loses lower end power (i sense someone's post- "we dont even have low end tq to lose to being with har har har"
also, if your theory was correct, he should go with 3inch diameter....no? LOL
I kinda said it wrong. you want a free flowing exhaust on a turbo set up after the turbo. between the head and the turbo is where pressure helps. The reason why a turbo spins is because energy release from the heat and the drop in pressure.
As for pressure in an n/a system. the engine does not do less work shoving exhaust in to pipes full pressure. that makes no sense. its like pumping a tire. it gets harder to pump the more pressure there is in the tire. the reason why you have a decrease in low end power, is because the volumetric efficiency of the exhaust flow goes down in lower rpms. adding a bigger exhaust simply sifts VEexhaust further up the powerband. Exhaust gasses will flow slower in the lower rpms the bigger the exhaust system is, and more exhaust gasses are stuck in the combustion chamber. That is why low end power is decreased.
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HondaLuver83
Well-Known Member
RickyG
Well-Known Member
So i guess the smarter thing to do would throw my question to hondaluver and nexttome, what should i go with?
and i don't have the headers yet i'm just trying to figure out what i need right now. but i'd look on ebay maybe?
and i don't have the headers yet i'm just trying to figure out what i need right now. but i'd look on ebay maybe?
