Oh, it'll pass emissions Yeah I'll take a look under the car and start simple and see how I like it
93GreenLX said:What would happen if I ran no exhaust, just a Pacesetter longtube header.
MidnightThunder said:You would harm and eventually kill your engine.
Yup, they get brunt, not bent.nomuffler said:The way I've heard it, the valves burn not bend. And it's not cause the air's cold (since it isn't). I've never heard a good explanation of why, but I'm trying to figure out a way for it to happen. Perhaps when there is valve overlap the piston can draw in extra air heating up the burn. But I gues as long as you have an O2 sensor the computer will richen it up? Does the 2.3 even have any overlap?
bhuff30 said:loss of hearing
multitude of tickets
pissed off neighbors
no girlfriend or friends
burnt exhaust valves
the biggest problem is cold air traveling up the header after you stop, and harming the exhaust valve.
But wouldn't the O2 sensor richen the mixture when it saw higher EGT?bhuff30 said:Yup, they get brunt, not bent.
The velocity of the exhaust passing past the valves is much higher with just an open header. This causes more heat transfer to the valves, and in extreme cases can burn a slot in them, which causes them not to seal any more. If you are running a low performance NA engine, I wouldn't worry to much about burning a valve. The velocties stay slow, and the EGT's low.
The O2 sensor looks at the A/F ratio, and it only does that in closed loop (cruise speeds).nomuffler said:But wouldn't the O2 sensor richen the mixture when it saw higher EGT?
Yeah, I get how it burns the valves. But wouldn't that heat the outgoing exhaust to? The O2 sensor determine the A/F ratio based on the temerature of the Exhaust gas, so it seems to me it'd richen the mixture whic DUH! damnit I just realized would't do **** to stop the burning valves. But, there's another downside, baad gas mileage de to the computer richening up what it thinks is a lean mix. Maybe? The computer only runs in closed loop at cruise? I thought they only did one or the other.bhuff30 said:The O2 sensor looks at the A/F ratio, and it only does that in closed loop (cruise speeds).
The problem isn't higher exhaust temps per say... it is higher exhaust velocities at the valve which causes more heat transfer to the valves. (just trust me on that, it has to do with renolds number, and I don't want to teach you heat transfer and fluid mechanics).
nomuffler said:Yeah, I get how it burns the valves. But wouldn't that heat the outgoing exhaust to? The O2 sensor determine the A/F ratio based on the temerature of the Exhaust gas, so it seems to me it'd richen the mixture whic DUH! damnit I just realized would't do **** to stop the burning valves. But, there's another downside, baad gas mileage de to the computer richening up what it thinks is a lean mix. Maybe? The computer only runs in closed loop at cruise? I thought they only did one or the other.
93GreenLX said:http://www.exhaustsoundclips.com/sound/ford_mustang_2.3_1991_openexhuast.mp3 I hope it didn't sound anything like this 91 2.3 that is just labeled as open exhaust
93GreenLX said:Yeah and definitely not what I want to sound like