bung welding

S

sixstring

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Where does one go in the GTA to get a A/F sensor bung professionally installed on their exhaust?

I'm assuming anyone with welding experience can do this? Does it have to be done with a certain type of welder MIG,TIG etc.?

Does the location and orentation of the sensor matter a whole lot?
 
The type of welding depends on the type of material. Stainless, titanium, or what is it? TIG will be best in either case, but not many welders have experience with titanium. Thin sheet metal is very tricky to weld. I can only tell you one thing about who can weld that ... not me.

The best location for the sensor is right at the spot where all cylinders join into one pipe. It needs to see the flow from all cylinders.

Lambda sensors want to be pointing downwards from the top of the pipe to avoid issues with condensation when the engine is turned off. Some reasonable variation off vertical is OK, it doesn't have to be dead straight, but avoid going in from the bottom half of the pipe.
 
talk to JohnnyP636 on here, he is out your way and has had this done for people.
 
AC said:
talk to JohnnyP636 on here, he is out your way and has had this done for people.
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True story Ive done a few, Titanium, Stainless doesn't matter I use TIG welding...
As mentioned the best location is right after that last collector where all the pipes connect to one, on some bikes you have to be careful that you have enough clearance
IMG_1218.jpg
 
For my car, I took the collector with a hole drilled in it and the bung to a muffler shop, it was $15 to get it welded. Both pieces were mild steel though, as stated above, make sure whoever you use has experience with your header material (and your bung is the same material, welding different materials is best avoided where possible).

+1 for the sensor draining. On the car, it is almost horizontal, just sloping slightly towards the tip and it has worked for a few years. I would prefer more vertical, but that wasn't an option given the space (the collector is behind the firewall, I would have had to cut the floor open and made a box around the sensor).

Aaron at weirtech in burlington also knows his stuff if you are ever that far west.
 
JohnnyP636 said:
True story Ive done a few, Titanium, Stainless doesn't matter I use TIG welding...
As mentioned the best location is right after that last collector where all the pipes connect to one, on some bikes you have to be careful that you have enough clearance
IMG_1218.jpg
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That is one nice job ma' man.
 
I have an SS pipe and both an SS and mild steel bung. I'd like to use the mild steel bung, because it's the proper length. I'm told it's pretty common to use mild steel bungs with an SS pipe and I'm just looking for opinions. The only welding I do is oxy/acetylene and SS isn't my thing. I'm going to take them to be TIG'ed.
 
TheDirty said:
I have an SS pipe and both an SS and mild steel bung. I'd like to use the mild steel bung, because it's the proper length. I'm told it's pretty common to use mild steel bungs with an SS pipe and I'm just looking for opinions. The only welding I do is oxy/acetylene and SS isn't my thing. I'm going to take them to be TIG'ed.
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Get the proper length bung in SS, welding different metals together isnt the right way to do this...SS bungs can be had for as low as $5-50...
 
Thats really nice stuff JohnnyP.

I don't have the pipe yet but I'm looking at the Akrapovic 20th Anniversary re-run of the 4-2-1 system for the ZX7R. I believe the headers and mid pipe are titanium.... unless they're stainless steel :p

So does the bung need to be welded where it goes from 4-2 or where it goes from 2-1?

Does the bung change depending on what kind of sensor I'm using? I'm basically looking at this setup so I can get my FCRs spot on. I'm guessing any wide band sensor will do?
 
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sixstring said:
Thats really nice stuff JohnnyP.

I don't have the pipe yet but I'm looking at the Akrapovic 20th Anniversary re-run of the 4-2-1 system for the ZX7R. I believe the headers and mid pipe are titanium.... unless they're stainless steel :p

So does the bung need to be welded where it goes from 4-2 or where it goes from 2-1?

Does the bung change depending on what kind of sensor I'm using? I'm basically looking at this setup so I can get my FCRs spot on. I'm guessing any wide band sensor will do?
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If you are using 1 sensor it goes after 2-1.

What is the output of the sensor going to? When I was researching WB O2, the sensor didn't matter nearly as much as the gauge (some were so bad they were worse than nothing [ie. 2 second delay, off by more than 1 etc.]).
 
sixstring said:
Thats really nice stuff JohnnyP.

I don't have the pipe yet but I'm looking at the Akrapovic 20th Anniversary re-run of the 4-2-1 system for the ZX7R. I believe the headers and mid pipe are titanium.... unless they're stainless steel :p

So does the bung need to be welded where it goes from 4-2 or where it goes from 2-1?

Does the bung change depending on what kind of sensor I'm using? I'm basically looking at this setup so I can get my FCRs spot on. I'm guessing any wide band sensor will do?
Click to expand...

It goes after the 2-1, as close to the collector as possible....The picture I posted is a GSXR Yosimura full system exhaust, and that is the location Yoshimura used. However they used the smaller size bung that fits the stock 02 sensor that comes on the newer GSXR's from the factory...So what I did was cut that off and replace it with the larger size that is used with the Bazzaz FI management system that I also installed for the customer...

If the pipe you buy is SS then you want an SS bung, if its Titanium then you want a Titanium bung...Welding different metals although it might stick, is not proper and I do not suggest it...Akrapoivc makes their exhausts out of both SS and Titanium, so you need to know which one your buying...

I have only seen 2 different size bungs used on motorcycles...All of the aftermarket FI management systems Ive worked with so far use the larger 18mm size bung, Ive only seen the 12mm used on stock bikes like the GSXR that already have an 02 sensor...

Big question is how do you plan to use an 02 sensor and fuel injection management system on FCR carburetors? If you want your FCR's spot on then you need to take it to a shop that has a dyno and experience tuning FCR's....
 
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JohnnyP636 said:
Get the proper length bung in SS, welding different metals together isnt the right way to do this...SS bungs can be had for as low as $5-50...
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1" SS bungs are not all that available. The ones I've found cost 4 times the amount to ship them then the bung itself. The current 1/2" I have was cheap, maybe I can get a second one and weld it together for 1 inch.
 
TheDirty said:
1" SS bungs are not all that available. The ones I've found cost 4 times the amount to ship them then the bung itself. The current 1/2" I have was cheap, maybe I can get a second one and weld it together for 1 inch.
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I have never seen any imperial size bungs being used on motorcycles.....18mm and 12mm are the only ones Ive seen....And I have installed PCC, BAZZAZ, and PCV auto tune units...

Riders Choice in Mississauga stocks 18mm BAZZAZ bungs in both SS and Titanium, but they are machined nicely and therefore expensive...But you can just walk in and buy one without having to order them
 
18mm is the automotive industry standard thread for an O2 sensor. Any wide-band air/fuel ratio gauge will be using that thread, not the smaller one. I've only seen the simple (narrow-band) one-wire sensors using the small thread, and that's not what you want.

If you are using this to tune carbs, you'll need a plain ordinary air/fuel ratio gauge since there's nothing to data-log. But, I've done it myself, and it saves a lot of guesswork and trial/error.
 
JohnnyP636 said:
I have never seen any imperial size bungs being used on motorcycles.....18mm and 12mm are the only ones Ive seen....And I have installed PCC, BAZZAZ, and PCV auto tune units...
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I'm talking about the length, not the thread. I have a 1/2" SS bung already and a 1" mild steel. I would like a 1" SS, but it's expensive to get them, but 1/2" are easy and cheap, therefor the welding together comment.

1/2 inch
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1 inch
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JohnnyP636 said:
It goes after the 2-1, as close to the collector as possible....The picture I posted is a GSXR Yosimura full system exhaust, and that is the location Yoshimura used. However they used the smaller size bung that fits the stock 02 sensor that comes on the newer GSXR's from the factory...So what I did was cut that off and replace it with the larger size that is used with the Bazzaz FI management system that I also installed for the customer...

If the pipe you buy is SS then you want an SS bung, if its Titanium then you want a Titanium bung...Welding different metals although it might stick, is not proper and I do not suggest it...Akrapoivc makes their exhausts out of both SS and Titanium, so you need to know which one your buying...

I have only seen 2 different size bungs used on motorcycles...All of the aftermarket FI management systems Ive worked with so far use the larger 18mm size bung, Ive only seen the 12mm used on stock bikes like the GSXR that already have an 02 sensor...

Big question is how do you plan to use an 02 sensor and fuel injection management system on FCR carburetors? If you want your FCR's spot on then you need to take it to a shop that has a dyno and experience tuning FCR's....
Click to expand...

The pipe is SS, only the can is Ti.

I don't need a FI management system just a AF ratio number. Surely AF ratio would be useful information for tuning?! Especially the getting the accelerator pump dialed in.

Who in the GTA knows their way around FCRs? Or even had FCR jets?
 
Absolutely a live air/fuel ratio is useful for tuning carbs. You can see the effect of main jet and needle jet and slow circuit changes and once you have an idea of which areas are rich and lean, predict which way things need to be changed.

Winner's Circle in Markham should have jets, etc.
 
TheDirty said:
I'm talking about the length, not the thread. I have a 1/2" SS bung already and a 1" mild steel. I would like a 1" SS, but it's expensive to get them, but 1/2" are easy and cheap, therefor the welding together comment.

1/2 inch
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1 inch
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How much is expensive? If you just want a simple one like the picture you posted, Im sure any machine stop with a lathe can machine you up one for cheap...
 
sixstring said:
The pipe is SS, only the can is Ti.

I don't need a FI management system just a AF ratio number. Surely AF ratio would be useful information for tuning?! Especially the getting the accelerator pump dialed in.

Who in the GTA knows their way around FCRs? Or even had FCR jets?
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Personally I wouldnt spend the money on FCR's for a sport bike unless I was going to have them properly dyno tuned

I have an FCR on my mini bike and just one carb cost me $700, mine was a specific kit for my engine size and runs pretty damn good on the factory installed jets...I still plan to have it dyno tuned eventually
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