DIY 2 into 1, cross type exhaust (new garage doors and light..)
#16
^^ I don't know why you would get more flames with the quieter exhaust.
It is I think unburnt fuel with the ecu trying to protect the engine and running things rich. Maybe the fuel is being 'collected' more or the exhaust flow is such that it can ignite easier with the quieter muffler? I only noticed it on mine in pics and video friends took, usually happens at the end of a straight or when shifting. I think it correlates to coming off the gas after WOT? The throttle body should close when you come off the loud pedal so it should not be getting any more fuel. But maybe the exhaust slows down enough that it can ignite? anyone know?
It is I think unburnt fuel with the ecu trying to protect the engine and running things rich. Maybe the fuel is being 'collected' more or the exhaust flow is such that it can ignite easier with the quieter muffler? I only noticed it on mine in pics and video friends took, usually happens at the end of a straight or when shifting. I think it correlates to coming off the gas after WOT? The throttle body should close when you come off the loud pedal so it should not be getting any more fuel. But maybe the exhaust slows down enough that it can ignite? anyone know?
My quiet exhaust was clearly running very warm, to restrictive. Temp may be an issue. It probably aloud more unburned fuel to "collect" in the mufflers if that is possible !
Yes it's when letting off the gaz to shift or at end of straights going from throttle to brakes.
It's pretty cool though !
#17
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I thought you might chime in Mike!
I don't know the expansion coefficients but your math and estimate lengths seems okay to me. I've removed everything but have not started cutting, so I could put it all back together without doing anything. There are no cracks or any problems, I was just thinking..
3/8 seem like a fair amount or do you think that's okay, that's 9mm. That seems like a bit to have the exhaust accept by bending??
I could see how things go with one side and if it's a lot of work, just do one side. Looking at it now, it looks kind of difficult to get things lined up when building and am surprised that I managed to pull off building the thing in the first place. hmmmm.
I don't know the expansion coefficients but your math and estimate lengths seems okay to me. I've removed everything but have not started cutting, so I could put it all back together without doing anything. There are no cracks or any problems, I was just thinking..
3/8 seem like a fair amount or do you think that's okay, that's 9mm. That seems like a bit to have the exhaust accept by bending??
I could see how things go with one side and if it's a lot of work, just do one side. Looking at it now, it looks kind of difficult to get things lined up when building and am surprised that I managed to pull off building the thing in the first place. hmmmm.
#18
Drifting
Mike
#20
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Have dove in, don't look too closely at the welds, seems my tig skills don't get any better if I only used the welder once or twice a year... just glad I'm not blowing holes in the pipe.
#21
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Check this out re: grey welds - I learned a LOT from Jody on his web site. Really good teacher and welder.
http://www.weldingtipsandtricks.com/...eel-welds.html
As for my math, one assumption I made is the exhaust system is a uniform 1200F - which I think is way too high. Not sure when your car is back on the road, but it would be interesting to see what the actual temperatures are. I will check my car in early March when its back on the road.
Cheers,
Mike
http://www.weldingtipsandtricks.com/...eel-welds.html
As for my math, one assumption I made is the exhaust system is a uniform 1200F - which I think is way too high. Not sure when your car is back on the road, but it would be interesting to see what the actual temperatures are. I will check my car in early March when its back on the road.
Cheers,
Mike
#22
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Thx for the link, I noticed that the gas still flows after I take my foot off the pedal...should leave welding head close to the weld as it cools, hadn't been doing that. Probably main problem. I'll do more welding today, I'll see if things improve!
#23
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Btw, anyone know if the exhaust flow is spinning when it exits the turbos? And if so in what direction? I ask because I think fluids flow better when spinning don't they? Like a bullet? Was thinking of adding a baffle in the proximal pipe so that the exhaust gases spin but don't want to spin in the wrong direction if already spinning...
#24
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Post welding shielding is important - it should be adjustable on your welder. I usually use 3 - 5 seconds. The idea is to shield the weld while it cools from the air - so make sure you have enough gas flow. Too much and you waste argon and you can disturb the weld.
#25
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On the miller diversion there's no adjustment for the post welding shielding, I also have firepower welder that does have an adjustment (among other settings). Looks like I'm getting a little better!? Forget the swirling exhaust, silly idea and don't want parts falling off inside..
#26
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I got the firepower when the miller broke and was off getting fixed. My impression is that the miller works better for aluminum. (Or at least the preprogrammed settings seem to work well for me). It's sort of fool proof as it only has 2 switches and one ****. On/off, steel/aluminum, and amperage.