do open headers make car run slow???
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do open headers make car run slow???
Twice i was running open headers, first when i put them on then when i sold my exhaust. Seems like i have real bad low end power. I thought it would the opposite since there would no air flow restrictions w/ no muffler or y-pipe , or am i just tripping *****.
#4
hahaha dude plz don't do it again? your gonna warp your exhaust valves dude. the car will probably run like **** where are your 02 sensors going? if you wanna have some good power gains just go exhaust dumps but never open header
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its cool i just ran open headers the two times maybe a couple weeks combined. did nothing to my o2 sensors tho. but i sure got some suck *** gas mileage w/ open headers.
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#10
Backpressure never = torque. Backpressure is always neegative, its scavenging you want.
Yes thats fine.
Yes thats fine.
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vacuum in the pipes when the throttle closes. thats how you get the popping in the exhaust. hot air+cold air sucked in =the popping. thats 1 way the o2's get messed up with the air hitting them. gen III may be different though.
thats also where the "cracked valves" topic comes in
thats also where the "cracked valves" topic comes in
Last edited by Revelation Z28; 11-17-2007 at 11:15 PM. Reason: english owned me
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I did it when i first installed my longtubes and i thought it was a blast. Especially when no one wants to be anywhere around the car because it's unbelieveably loud Be a great idea to make people get out of your way in traffic when your in a hurry. Just rev at them and they'll move right out of the frickin path. They did in my case Even though i gaurentee the were most likely calling me an a**hole as I went by.
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vacuum in the pipes when the throttle closes. thats how you get the popping in the exhaust. hot air+cold air sucked in =the popping. thats 1 way the o2's get messed up with the air hitting them. gen III may be different though.
thats also where the "cracked valves" topic comes in
thats also where the "cracked valves" topic comes in
Popping ~generally~ comes from excess gas running though the engine into the pipes and being ignited by the hot exhaust parts.
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air is CONSTANTLY running intake->exhaust, there is no vacuum in the pipes at any time when the engine is running. Also, you really think cold air will make it all the way up the header and make it to the valves and still be cold? Even if it could make it all the way up there (which it can't), it's gonna be alot hotter from traveling up a 500 degree header than the air that is CONSTANTLY hitting the valves from the intake side. It's totally illogical.
Popping ~generally~ comes from excess gas running though the engine into the pipes and being ignited by the hot exhaust parts.
Popping ~generally~ comes from excess gas running though the engine into the pipes and being ignited by the hot exhaust parts.
sucks too cause i wanted to drive the car open LTs but was afraid of that happening
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I'm not saying there are no dangers if run that way regularly, but it isn't for the reasons most people give, and it isn't as big of a deal. Tons of people run dual cutouts right after the headers and never have a problem. I would recommend against long-term open headers
#17
vacuum in the pipes when the throttle closes. thats how you get the popping in the exhaust. hot air+cold air sucked in =the popping. thats 1 way the o2's get messed up with the air hitting them. gen III may be different though.
thats also where the "cracked valves" topic comes in
thats also where the "cracked valves" topic comes in
thats why they had diverter valves on the old air pump setups, they would blow out the muffler when they went bad.
#19
biggest issue with open headers is killing the o2 sensors, great way to mess those up.
as for no power in the low end, it's the scavenging, more power is being sapped to "push" the exhaust air out rather than scavenging helping to pull air out of the exhaust.
as for air travelling back up the pipes while it is running, what kind of nonsense is that? Sure there's a "little" overlap between intake and exhaust but during the intake stroke, the exhaust valve is for the most part CLOSED meaning it's drawing air from the intake. The overlap is also what slows down the air after the exhaust stoke further cementing that without scavenging at low rpm, the exhaust air speed is slowed down even further.
Once you get up in the rpm, the free flow of the exhaust outweighs all that giving a nice healthy boost in top end hp and torque...
as for no power in the low end, it's the scavenging, more power is being sapped to "push" the exhaust air out rather than scavenging helping to pull air out of the exhaust.
as for air travelling back up the pipes while it is running, what kind of nonsense is that? Sure there's a "little" overlap between intake and exhaust but during the intake stroke, the exhaust valve is for the most part CLOSED meaning it's drawing air from the intake. The overlap is also what slows down the air after the exhaust stoke further cementing that without scavenging at low rpm, the exhaust air speed is slowed down even further.
Once you get up in the rpm, the free flow of the exhaust outweighs all that giving a nice healthy boost in top end hp and torque...
#20