I have determined that this is an additional input data stream I would like to have.

I have noticed that AEM has a "kit" for this; however, the kit is just a 5 Bar Map sensor and pigtail.

What does everyone on here do to keep from getting the sensor too hot? Pictures would be very helpful!

I currently have 1/8 NPT taps in both the pipes off #3 and #7 i think on my PTK kit, which I was thinking I could use for my sample port. I imagine the collector would be better; however, this would require modificiations.

 

I was told to run a small metal line from the header/collector to the sensor but I have yet to see it done. I would like to know how far it needs to be from the header to have enough drop in temp not to harm the sensor.

 

I was told by Precision to run 1/8 inch soft cooper tubeing, looped several times to drop the temp.. And hooked to some cheap pressure gauge..

They said as long as my exhaust pressure didn't exceed 2 times my intake pressure.. That I was OK...

 

If you where to loop the tubing, would that not cause a pressure drop in the tubing and make the reading erroneous?

I guess at high boost it may not be enough to worry about.

 

What would be the best way to connect a 1/8'' copper tube to a female 1/8'' NPT port that will handle ~50 PSI (any maintenance men in the house)?

Also, the length of tubing is very important. Does anyone have some real info on how long is needed?

I spent an hour on here last night searching for these details without luck.

 

No exhaust flow actually goes to the sensor. If there is no flow, then there is no pressure drop using small tubing. Also, if there is no flow, then no heat makes it to the sensor. Think of it this way, most of the gas in the tubing will stay there and only compress under pressure, then decompress.

I have a 1/8" NPT bung welded to my collector just before the turbine. When I take pressure readings, I screw in a 6" long 1/8" pipe. That 6" is enough distance to isolate header heat from the rubber hose on the other end. I then run the rubber hose to a gauge clipped under the windshield wiper. The rubber hose never gets hot.

Mike

 

Nitpick: if the volume is compressing, then there is flow initially coming into the tube to compress the volume that previously ocupied the tube.

However, besides this initial flow to equalize pressure, there is no flow through (stagnate volume), which means not a great deal of heat energy will be traversing into the tubing since it is plugged on the other end = not too high temp for the sensor.

I hadn't been thinking of it quite like that; however, for a very small dia pipe with relatively long length (say L = 50 diameters which is about 6'' lenght for a 1/8'' pipe) there probably would be very little temp influence on the other end. Neat.

Thanks for the enlightenment mike. What kind of fittings do you use to connect the copper tubing to the exhaust piping? I have never dealt with copper tubing before.

 

I don't have copper tubing at all. It's a 1/8" pipe, then a 1/8" pipe to hose barb adapter, then rubber hose.

Mike

 

That sounds really simple. Thanks.

What MAP sensor do you use or recommend?

 

I'm not logging backpressure. I just installed a gauge a few times to check it when modifying the exhaust system.

 

Ah, I am thinking along the lines of logging both pre-turbine and perhaps in the downpipe so that I can get an idea of how much my exhaust is choking me.

I was only planning on logging one at a time and just moving the sensor between bungs.

What are good/bad post-turbine pressure readings??? How much is acceptable with a full exhaust?

 

Of course, 0 is best. <5 psi would probably be acceptable. >8 psi probably warrants some money to be spent.

 

If you are going to use 1/8" copper line, just get a brass 1/8 NPT x 1/8 compression fitting. That's what I have used in the past.