How many?
Ideas on placement?
Headers.

 

In the bung holes, of course.

Doug

 

 

In the collector should be fine. Install it so that condensation will not collect in the O2 sensor. You can do one or both sides.

 

And check before hand that the sensors will not hit the frame, or the scatter shield, or anything else. I got lucky, barely, on missing the scatter shield flange. Didn't even think about it when i drilled the holes.

Doug

 

Geez....this must be the "black car" thread. Niiiiiiccccccccce!!!!!!!!

I was thinkin' in the primaries.............in 1,3,5,7..........to get both sides of the intake fer possible stagger jetting.........it's a dual plane intake.

What say you?
Pithy replies appreciated.
Hyphenated word for the day is "bung-hole".

 

I've heard of this with the condensation but I get it. Why would you get condensation coming straight down but not from the sides. I don't see a difference wet is wet. Can you explain?

 

Every see water run out the tail pipe of your car? Vapor is different than straight liquid

Doug

 

Doug,What is the difference whether on the top or the side, it will still get wet. Once the engine reaches running temp the condensat is gone. I don't understand why top bad ,side good. The water vapor is going to get to the sensor in either spot.

 

Bung Hole, just sayin' it makes me laugh!

 

Me too.

 

Imagine a bunch of condensed water in the bottom of your exhaust pipe of your recently started car, now imagine your O2 sensor self heating to 650 degrees F, which it does in about 1 minute, now imagine hitting the brakes and a bunch of water rolls forward and hits that 600* ceramic element.

I didn't make this sh*t up and neither did Vetrod, it is part of the instructions on the sensor.

Doug

 

Nice accurate response Doug.

Quotes from blue63cpe:
First, it is unlikely that every time you start your car, 100%, that it will reach running temps. Yes, it is the best way to do it, but some times it just does not work out and water sits in side the sensor. Wide range Bosch 02 sensors are expensive.

Secondly, No one said you can not on top of the collector. But I can not see how you could possibly use it, other than cutting a hole thru the carpeting and floor. The O2 sensor and fitting can be as long as 6".

 

Doug's car is a beautiful dark blue. But no foul there.

Checking primaries for A/F ratios on an over the counter duel plane for each cylinder would be an exercise in dumb. Each pair of runners would be of unequal lengths, volume and velocity. Getting each cylinder to have the same A/F would be almost impossible. Total waste of time for the improvement, if any, vs the improved HP or mileage. If this is so important, go for sequential FI. ( If you have a really badly designed manifold, it might help in that corner, but I would replace the manifold before going thru all that.)

As O'Reilly says, Pithy enough??

 

Bosch recommends putting the sensor in a vertical run of pipe, which would guarantee isolation from condensation splash. If placed on a horizontal run, then they recommend clocking it anywhere between 10 and 2 o'clock position. They also limit gas temp to about 1000 degrees C, which is (about) 1800 degrees F. 1800 degrees F is (supposedly) the EGT at Stoichiometric, and thus happens rarely. Zeitronics recommends placement at least 18" downstream of the head flange, but Bosch has no such minimum recommendation. It is important to place the sensor in a location where the EGT is above a minimum temp, otherwise skewed readings will result. It seems that ideal placement would be anywhere between 12" from the head flange, to near the collector outlet. With all of this in mind, I'm leaning towards placing a bung in each primary tube, 1,3,5,7, in the vertical runs, approximately 15" downstream of the head flange.

I have an LT1 intake, which is a damn well designed dual plane manifold. I've never played with stagger jetting and am willing to take the time to get the ratios as closely matched as I can.

I'm looking for input from people who have experience with this. If someone can say from experience that this is a waste of time, then that would be appreciated, along with reasons therefor.

If individual cylinder tuning is fruitless, then placing a single bung in either collector, clocked between 10 and 2 o'clock is all that is necessary. There would be absolutely no reason to place an additional bung on the opposite collector, since the bung placement is averaging the ratios of cyls 1,3,5,7 and 2,4,6,8. If someone has any valid reason for placing a bung in EACH collector, rather than on only ONE side, then pipe up.

 

http://wbo2.com/lsu/lsuinstal.pdf Here's a pdf I found on sensor placement,which seems to be a science in its self. Guys I never said that you were making this up, I've heard this before. I was just wondering why.