Jarle
If your exhaust system is going to be the same length as your motorcycle exhaust system then you won't have a problem. Since this is not likely, you WILL have a problem. The reason is that the gases in the motorcyle system do not reach a suffiently low dew point temperature before they pass out of the system. Therefore it's not an issue as you say.
In a car, the system is much longer and dewpoint is reached around the rear axle area typically. This is why traditionally the rear muffler usually corrodes out before the front one due to the acid attack being more aggressive there.
The reason why manufacturers chose to lag exhaust systems by cladding them is to maintain as high a temp as possible not only for the Cat. to work properly but to minimise the effect of dew point from temperature drops along the length of the system.
I would recommend you finish your excellent project with stainless instead of aluminium because the weight difference will be neglible but the you will have a lifetime system for your efforts.
At the end of the day, the value of this site is to teach each other what we know to spread the knowledge. What you do with that information, is up to you.
Hey Mr Zee
There are many things you can do with a goilet- just ask JK.
If your exhaust system is going to be the same length as your motorcycle exhaust system then you won't have a problem. Since this is not likely, you WILL have a problem. The reason is that the gases in the motorcyle system do not reach a suffiently low dew point temperature before they pass out of the system. Therefore it's not an issue as you say.
In a car, the system is much longer and dewpoint is reached around the rear axle area typically. This is why traditionally the rear muffler usually corrodes out before the front one due to the acid attack being more aggressive there.
The reason why manufacturers chose to lag exhaust systems by cladding them is to maintain as high a temp as possible not only for the Cat. to work properly but to minimise the effect of dew point from temperature drops along the length of the system.
I would recommend you finish your excellent project with stainless instead of aluminium because the weight difference will be neglible but the you will have a lifetime system for your efforts.
At the end of the day, the value of this site is to teach each other what we know to spread the knowledge. What you do with that information, is up to you.
Hey Mr Zee
There are many things you can do with a goilet- just ask JK.
Transaxle Alfas Haul More Arse
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Greg I am quite happy for you to disagree with me. I have provided rational explanations of why the case is what it is.
Now if you care to provide Jarle a similar rational ( or beter still a scientific ) explanation of why is it's not, the guy will have a balanced argument from which to make up his own mind.
I have known about the issue for over 30 years and I am reasonably happy with what I know to be the facts.
Now if you care to provide Jarle a similar rational ( or beter still a scientific ) explanation of why is it's not, the guy will have a balanced argument from which to make up his own mind.
I have known about the issue for over 30 years and I am reasonably happy with what I know to be the facts.
Transaxle Alfas Haul More Arse
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Here is the explanation of why the exhaust can't cool to the dew point temperature.
Dew point is the temperature to which air must be cooled to become saturated. It other words when the temperature drops to the dew point the moisture in the air becomes visable (ie rain, drizzle, fog, dew, etc.)
Now, the dew point is never below the ambient temperature. I have to write down all the weather data at least four times a day at my job, and I have never seen a dew point temp below ambient.
While I don't have an exhaust gas temp gauge near the end of my tail pipe, I am pretty sure the temperature of the exhaust comming out of the pipe is well above ambient. That pipe itself is certainly hotter, not colder than the surrounding air.
If the exhaust comming out of the tail pipe is warmer than ambient then it's not below the dew point.
If you can show exhaust temp data where the temp is below ambient, or a weather report where the dew point could be above the exhaust gas temp, I would love to see it. Heck, if you could show a weather report with a dew point above ambient, I would be pretty excited.
Dew point is the temperature to which air must be cooled to become saturated. It other words when the temperature drops to the dew point the moisture in the air becomes visable (ie rain, drizzle, fog, dew, etc.)
Now, the dew point is never below the ambient temperature. I have to write down all the weather data at least four times a day at my job, and I have never seen a dew point temp below ambient.
While I don't have an exhaust gas temp gauge near the end of my tail pipe, I am pretty sure the temperature of the exhaust comming out of the pipe is well above ambient. That pipe itself is certainly hotter, not colder than the surrounding air.
If the exhaust comming out of the tail pipe is warmer than ambient then it's not below the dew point.
If you can show exhaust temp data where the temp is below ambient, or a weather report where the dew point could be above the exhaust gas temp, I would love to see it. Heck, if you could show a weather report with a dew point above ambient, I would be pretty excited.
Jim,The Aussies are a clever bunch..they invented the tiolet seat...It took the English 200 years to put the hole in it!!!!!!JimGreek wrote:Hey MD, we do use the toilet here too...is this goilet an improved version (hence the spelling to differentiate)?? If you use it too, how do you mount them on trees?
Jim K.
French cars are shit and shit expensive to service and bloody awful and unreliable and expensive and friends don't let friends drive french cars and you wait years for parts.
You're probably right Barry, but I hear around where MD lives they're having a few problems as seen in the attached pic!
Has it occurred to them they should connect these things to a pipe or something?
Jim K.
The picture was removed to reduce the smell of fermenting fertilizer.
Has it occurred to them they should connect these things to a pipe or something?
Jim K.
The picture was removed to reduce the smell of fermenting fertilizer.
Last edited by Jim K on Sun Jan 21, 2007 5:03 am, edited 2 times in total.
Hey JK,
You're a scholar and a gentleman for removing the photos.
Mate, you can sling all the crap you can muster as usual but I just don't wanna see it in smellavision. Glad we go that sorted. Thank you.
You're a scholar and a gentleman for removing the photos.
Mate, you can sling all the crap you can muster as usual but I just don't wanna see it in smellavision. Glad we go that sorted. Thank you.
Last edited by MD on Tue Jan 23, 2007 12:20 am, edited 1 time in total.
Transaxle Alfas Haul More Arse