5 replies to this topic

[colinu]

Engine rebuild is pretty much complete and I hope to drop it into the Mini in the next few weeks. As I don't have access to a "Mini knowledgable" rolling road I'm going to road tune this normally aspirated non-MPi engine by fitting an o2 sensor and wideband AFR guage.

QUESTION: Where should I fit the sensor/bung in my LCB?

I see that the Maniflow MPi LCB has it fitted just below where the outer pipes join (i.e. sniffing the outer cylinders which are a little leaner than the centers), but I'd have thought a better place would be further down in the LCB's collector. Only problem I see with that is there's little (if any!) space to fit it there without it fouling the floorpan.

So, has anyone done similar before, and ideally do you have a photo (or good description) of exactly where you placed the bung/sendsor?

Cheers,
Colin.

FYI... it's a 1380cc, with HIF44, and MegaJolt

[Sprocket]

It is better to weld the socket into the 'Y' piece at the common collector. This will give the average of all cylinders, rather than just the outer cylinders as on a Maniflow or similar LCB. The standard cast iron manifold actually senses the average of all the cylinders as it has a passage into both downpipes.

[colinu]

Yes, fitting it to the common collector it where I think it should go too. Ideally I'd like to know the exact position of where I should drill the collector (a photo would be great!). Just trying to save myself the hassle of fitting the engine,dry fitting the exhaust, figuring out the best location for the O2 sensor (i.e. best fit without fouling the floor pan etc), then having to remove the exhaust, drill, weld, blah blah, refit...
It would be much easier to know exactly where to drill the collector and weld in the bung in advance of fitting the engine/manifold/exhaust

[colinu]

Yes, I've read that too (and that it should be angled at least 10deg upwards to let condensation drain out) . Either position I'm considering is greater that 18" away... the advanage of fitting in the collector (IMHO) is that the sensor will sniff all cylinders as opposed to just the leaner 1 & 2 cylinders. I just can figure out if there's really enough room to fit it to the collector easily.

[Sprocket]

fit it on the passenger side, plenty room Thats where I had mine without any problems. I wouldn't be too concerned about the upward angle so long as you don't put a downward angle on it. I doubt any water would collect in it fitted perfectly level in the side, and the sensor tip is heated to 500c anyway. Plus the fact that condensation will form on all surfaces when its stood still and cold, despite the orientation.

[colinu]

OK now I know which side to fit it - but will dry assemble to find the exact location before drilling a hole in the collector