neptuner

I have the SOT SC kit with emanage ultimate. Peak boost is about 10 psi in the summer and as high as 11.8 in the winter. These pressures have been verified by logging the OEM MAP sensor output and by the cavlico boost sensor I use with my Zeitronix display.

I want to replace the OEM MAP sensor but I am not sure if I should go with a new OEM or with a 2-3 bar aftermarket sensor. I have read that the OEM MAP sensor is good only to 10 psi and may be damaged/inaccurate if exposed to higher pressures. The OEM sensor has 110K miles on it (30K boosted)and worked OK until recent problems.

I would like to go with a 2-3 bar sensor but I am not sure if some settings or wiring would need to be changed. It may also be possible to use the output from the cavlico boost sensor but I do not know how.

Should I:
1. Replace with a new OEM MAP sensor
2. Replace with an aftermarket 2-3 bar MAP sensor. If so, which one and what does it take to make it work correctly?
3. Use the output from the Cavlico boost sensor that I alreday have. If so, how do I do this?

Torque Obsessed

If your OEM sensor is giving you trouble, I'd probably just replace it.
What I did, and what I think most other e-manage ultimate owners do, is leave the OEM map sensor as is and clamp its voltage at 2.85V inside the EMU. That way the EMU uses the OEM sensor when you are not in boost, but stops reading above 2.85V (which is 0psi gauge).

Then use a separate sensor to read values >0psi (when in boost). I bought the Greddy pressure sensor and connected it to the vacuum lines running to the fuel pressure regulator, then plugged it into the EMU. You could use the Cavlico for this. Inside the EMU, just enter values to calibrate it so the EMU knows what boost pressure corresponds to the voltage the sensor sends.

Wiring it into the EMU can be done in different ways. I would buy the Greddy cable for this (because it has a nice plug-in connector that goes into the EMU) and just splice it into the wires coming off the Cavlico. I think someone in the UK actually used an old hard drive connector to wire in his O2 sensor because it was a similar connector. If that's too much work, just buy the Greddy pressure sensor and matching harness, and then it's all plug-and-play. That's what I did.

FRSport sells the Greddy sensor and wire harnesses. I'd look into one of the two harnesses toward the bottom of the page @ the following link.

FRSport - Greddy pressure sensor

neptuner

Thanks for the reply. Your advice makes sense to me. I just ordered an pressure sensor harness for the Ultimate and will use it to tie in the Cavlico pressure sensor. I still need to order a replacement OEM MAP sensor too.

vader1

Neptuner,

I run the Greddy sensor and it seems to work really well. I was also seeing higher boost pressure just like you but I replaced my coils with RSX coils and noticed two of the plugs were loose so I re-torqued them down. My boost now peaks at about 9 so far. I don't know if any of that was related but FWIW I am seeing much lower boost now.

I also saw slightly higher boost with a Fujitsubo than with the stock exhaust so I went back to stock. Your header and exhaust combo might have something to do with the higher boost.

John

neptuner

How do you like the RSX coils? I am still running the OEM coil packs with 110K miles on them.

vader1

I had my car dynoed and it peaked at 278hp at about 7500 and then fell off and blew black smoke. LOTS of it. This should have occured to the tuner that my spark was blowing out but he was a dipsh*t. I did find a loose plug and retorqued, checked my gaps and they were fine and figured I would throw in a new set of RSX coils for good measure because they were cheap. I have not been back to the dyno yet but something must be better. It does not blow black like a diesel above 7500 anymore and things also seem smoother. My coil packs only had 30k on them but I had a feeling something was up with one or two and did not know how to diagnose them individually so a whole new set for $160.

I read the threads about flakey AP1 coils, good luck with RSX coils and bought into the hype but the car runs better than it was. But I actually had a problem I could see on a dyno chart and out of the tailpipe. If you don't I am not sure you will notice any difference or not.

neptuner

My car is running fine at high rpm and in boost. The only issues I have are at idle and sputtering after sitting at a stop, especially when hot.

Revenge

I thought you had to run the greddy one

vader1

I think this is a common problem and idiosyncracy with the kit because of where the air pickup is. I thought you had posted a while back you were doing the NACA duct but I don't rememebr for sure. I have not done that and think it would certainly help. I talked to Mark on the phone about it the other day and one thing he suggested was to check the throttle postion sensor voltage as per the instruction manual and set it on the low side if you can. Then tweak the idle screw in minute increments until you get a smooth idle. He said he did this on his own car and it helped a lot.

Secondly, when the car sits in traffic or hot starts you get all that heated air in the intake tract. A while back he had kind of walked me through how to data log for seeing what kind of temps the car was seeing in those circumstances and setting up some kind of vairable where the fuel and timing would be changed to compensate for those conditions of extreme intake temp (sitting in traffic). I did not follow it and did not want to try for fear of screwing things up.

But I come in after some hot day runs and the barrel feels cool but every other part of the intake tract is HOT and I am sure that has an impact. I want to do the naca duct, shield the filter from the header, and see if I can work an air guide from below to scoop under car airflow up to the filter but have never gotten around to it.

I am sure there is a way to tune for the hot air after sitting, but I am the wrong guy to ask. It is pretty obvious though that while you sit, super hot air just rises off the header and gets sucked into the filter.

Kitesurfer s2000

This sorted it for me 1m flexi pipe down to the old AEM v2 position.