Hi,
I have cast exhaust manifolds with a Pypes aftermarket X-pipe dual exhaust. They are connected by scrap pipe that was welded to the Pypes system at the crossmember and connected to the flanges at each manifold. I’m looking to add a wideband O2 sensor for an air/fuel gauge. The engine is not EFI but I still want a gauge to obtain readings. Where would be a good spot to place the bung for the O2 sensor?

 

Either side before the X-pipe would be fine. Also make sure the tip faces down, even just a little.

 

Mine are about 6-8 inches from the exhaust manifolds in the downward sloping pipes, in case that helps.

 

Thanks!

 

Thanks, it definitely helps! It’s about where I figured I’d have most space but wasn’t sure.

 

On the same subject, What brands are recommended? What would be a middle quality and what would be a high quality? Does it matter what one you buy if you are carbureted versed Injected? I assume it would be the same? I am about ready to get one and learn to use it.

 

This was something I researched as well. Most of the more reliable components come with either Bosch, Denso or NGK sensors. Due to the high heat and resistance to any moisture, these brands have a better life.

Sensor would be the same for carbureted or fuel injected, the difference is in what is deciphering the readings. For example, a carb engine the reading would be connected to a mechanical or digital gauge and wouldn’t automatically make any adjustments but in an EFI setup, it would communicate to the module or ECM and the system would adjust or send an error.

 

Ive been using the DM-6 from PLX for over 3 years now on my air cooled VW engine. Was dual carb and now EFI running a Microsquirt ECM. It uses the Bosch 4.9 sensor and doesn't require free air calibration. It has a little touch screen guage, but I also see what it sees on my laptop computer with the EFI.

Since you're into the forced induction stuff, I recommend any good wideband. All brands have their fans and people who've had bad luck, its hard to see which is truly the best one out there. I've been able to tune out some things that were impossible before. Running a big modified engine in a VW Bus, it was clear that the un-aerodynamic shape and low gearing required big changes compared to running the same engine in a Beetle. Fixing your transitions between fuel circuits is just the beginning. Once I switched to EFI, I could not figure out the backfiring in between shifts for awhile. I cut the pulsewidth on the injectors and that fixed my problem, too much fuel spray was accumulating raw fuel in the muffler. You do have to keep in mind that the wideband is measuring AIR, so, in my case, it was not fully sensing the raw fuel going to my muffler after the sensor!
The other day I hauled a huge amount of dirt (my Bus is a Pickup actually) and also recently stones and gravel. The torque and driveabilty you get from tuning is a night and day difference. It is totally worth the $200.