will running straight pipe blow the motor?
01-30-12, 12:57 AM
#1
will running straight pipe blow the motor?
i bought an N/A s5 recently with full headerback straight piped exhaust, with the O2 sensor unhooked, i read something about someone blowing their motor due to the straight pipe not having enough back pressure and i guess it was running too lean or something like that? i'm not sure, but i really wouldn't like to blow my motor.. and i've never heard of this happening until i read that thread.. i was wondering if hooking up O2 sensor(because mpg) would maybe make it run lean and blow? what do you think?
01-30-12, 02:13 AM
#2
Rotary Enthusiast
Turbo engines with no exhaust and a fuel cut defencer run to lean and blow.
With an NA, no worries. If someone claims that, they aren't very bright and probably did something else wrong.
With an NA, no worries. If someone claims that, they aren't very bright and probably did something else wrong.
01-30-12, 02:29 AM
#3
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i bought an N/A s5 recently with full headerback straight piped exhaust, with the O2 sensor unhooked, i read something about someone blowing their motor due to the straight pipe not having enough back pressure and i guess it was running too lean or something like that? i'm not sure, but i really wouldn't like to blow my motor.. and i've never heard of this happening until i read that thread.. i was wondering if hooking up O2 sensor(because mpg) would maybe make it run lean and blow? what do you think?
Im running straight pipe. But runs better with at least a good exhaust. Seem to have better power with at least 0.50lbs of back pressure
01-30-12, 07:34 AM
#5
01-30-12, 07:40 AM
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Hrm... I have a Turbo motor, 3" catless N1 Style exhaust from front to back.. FCD built in to ECU. I had not heard that this was a recipe for exploding apex seals...
So Do I need to add a boost controller?
So Do I need to add a boost controller?
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01-30-12, 01:00 PM
#13
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however its not because it wants backpressure, but i think because the stock ecu tune doesn't work very well @wot under 4500rpm with the straight pipe* if you tuned the ecu with the straight pipe it would make more power.
as for blowing the engine, the S5 NA runs so rich that its fine, if anything it runs a little richer when its opened up.
*going WOT, it feels like it makes noise, but doesn't go anywhere, so its either too lean, or its too rich and not enough timing or something, i didn't check. it was also too loud and too stinky so i put the cat back on it....
01-30-12, 01:57 PM
#14
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i noticed this too. my S5 feels like it makes more power with the cats vs straight pipe under 4500rpm.
however its not because it wants backpressure, but i think because the stock ecu tune doesn't work very well @wot under 4500rpm with the straight pipe* if you tuned the ecu with the straight pipe it would make more power.
as for blowing the engine, the S5 NA runs so rich that its fine, if anything it runs a little richer when its opened up.
*going WOT, it feels like it makes noise, but doesn't go anywhere, so its either too lean, or its too rich and not enough timing or something, i didn't check. it was also too loud and too stinky so i put the cat back on it....
however its not because it wants backpressure, but i think because the stock ecu tune doesn't work very well @wot under 4500rpm with the straight pipe* if you tuned the ecu with the straight pipe it would make more power.
as for blowing the engine, the S5 NA runs so rich that its fine, if anything it runs a little richer when its opened up.
*going WOT, it feels like it makes noise, but doesn't go anywhere, so its either too lean, or its too rich and not enough timing or something, i didn't check. it was also too loud and too stinky so i put the cat back on it....
01-30-12, 04:00 PM
#15
My car stinks Bad. I mean Just backing into the garage and shutting car off smells up the house. I never have a tailgater. I am always looking in my rear view to make sure no cop is smelling my exhaust. Cause that could be bad. Its funny though I will get a tailgater very rarely then after 5 seconds they back off and then go around. they never hang out
01-30-12, 05:41 PM
#17
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My car stinks Bad. I mean Just backing into the garage and shutting car off smells up the house. I never have a tailgater. I am always looking in my rear view to make sure no cop is smelling my exhaust. Cause that could be bad. Its funny though I will get a tailgater very rarely then after 5 seconds they back off and then go around. they never hang out
01-30-12, 07:25 PM
#18
Rotary Enthusiast
If your ECU has one built in, I'm assuming an Rtek, then you have some way to control the fuel. So you're in the clear.
01-30-12, 11:56 PM
#21
If you have a good pair of mufflers (ie stock or RB), the sound levels can be semi-tolerable with a straight pipe alone, but the highway drone gets annoying. Toss in a header, and all bets are off.
A full RB exhaust does not use a straight pipe. It'll have a presilencer, which is not at all the same.
No.
Where the heck do these rumors come from?
Originally Posted by nycgps
A straight pipe makes ur car smells like ****, thats the biggest reason why i sold the full rb set that came with the car.
Where the heck do these rumors come from?
Last edited by RotaryRocket88; 01-30-12 at 11:58 PM.
01-31-12, 01:51 AM
#24
well i have an sdj header(gangster) straight, and i mean STRAIGHT *** pipe from that to a RB muffler.. i was just wondering if connecting the O2 sensor would hurt.. thanks.
and F*CK yes its annoying driving more than 1 mile at a steady rpm.. it almost puts me to sleep sometimes driving 15 miles to/from work.. its like a loud humming lullaby hahaha
and F*CK yes its annoying driving more than 1 mile at a steady rpm.. it almost puts me to sleep sometimes driving 15 miles to/from work.. its like a loud humming lullaby hahaha