3 bar MAP sensor + stock tuning/turbo...

I'm installing an upgraded SMIC today, and I just found out that my new IC is drilled for the 3 bar MAP sensor, not the stock sensor like I had requested. Even though I'm installing this thing today, I bought the IC a long time ago, so returning it is not an option at this point.

I guess my options are...

1. Put the stock IC back on, and install the IC at a later date when I have a new clutch and chip

2. Drill out the MAP sensor hole to accommodate the stock MAP sensor

3. Install the new IC and a 3 bar MAP sensor...then drive like a granny to keep boost levels low until I get a clutch and chip (ASAP)

I know #1 is the best solution, but I have to leave for a 500 mile trip in 3 days...

I have my mods listed in my signature...the most relevant info is that I have a stock turbo, clutch, and tuning. What should I do? Just how dangerous is option #3? (i.e. "kinda", "extremely", "*** why would you even consider this")

Hrmm I guess I could also pick up a q-loader and request a stock-like tune with the 3bar MAP sensor...then upgrade my tune later when I have a better clutch. I may just do that.

I would be hesitant to drill out the hole unless you have a proper ream. Otherwise it may not seal properly. I would think a 3 bar map sensor would be okay, but if you're worried about it then you could also run a boost valve (which would be cheap insurance) to make sure boost doesn't get out of control.

Just get a 2.5bar map from a PD100 (038906051B). It shares the smaller diameter as the 051C.

I'm sure alot of PD guys changed out their 2.5's for a 3bar and have them sitting around collecting dust.

I looked but don't have any here. Go ahead and run the 3bar, but no high speed runs, it can give 6psi more boost

Jeff

I just realized I think I might have a little 2.5 bar map sensor.

here's a pic of one $67

http://www.worldimpex.com/parts/genuine-part-boost-pressure-sensor_201817.html

I'm going to try to find one of these little 2.5 bar sensors locally...I found someone who may have one available, but I'm not 100% sure it's the right part #. We'll see in the morning. Otherwise I'll see if I can find one on here somewhere.

I went ahead and ordered the 2.5 bar PD MAP sensor. Thanks for the help!

jsrmonster said:

Just get a 2.5bar map from a PD100 (038906051B). It shares the smaller diameter as the 051C.

I'm sure alot of PD guys changed out their 2.5's for a 3bar and have them sitting around collecting dust.

I looked but don't have any here. Go ahead and run the 3bar, but no high speed runs, it can give 6psi more boost

Jeff

Click to expand...

Hi Jeff, could you please explain what gains (if any) are to be had if I were to change my stock MAP sensor for the 3bar? I have RC1+ that you put on back in Madison GA about a year ago.

If no gains, what are the dangers? I've got the stock turbo and clutch still, boost valve sitting on the shelf. Many thanks.

The OP has a rotary pump TDI, the PD's will give cel and overboost unless they are programmed for 3bar map. Don't do it.
Jeff

andreigbs said:

Hi Jeff, could you please explain what gains (if any) are to be had if I were to change my stock MAP sensor for the 3bar? I have RC1+ that you put on back in Madison GA about a year ago.

If no gains, what are the dangers? I've got the stock turbo and clutch still, boost valve sitting on the shelf. Many thanks.

Click to expand...

Thanks, got it. I did some reading later on and saw that, unless one is running a bigger turbo and other supporting mods (esp. tuning for it!) a 3bar MAP sensor is asking for trouble.

What are the stock MAP sensors and would a 2.5 on a PD be bad too?

(on a side note would it be beneficial to swap in a bigger MAP sensor on a chipped 5.9 Cummins or what is the Cummins equivalent of the MAP sensor)

0Silva1 said:

What are the stock MAP sensors and would a 2.5 on a PD be bad too?

Click to expand...

To answer your question...

jsrmonster said:

Just get a 2.5bar map from a PD100 (038906051B)...

Jeff

Click to expand...

I believe the PD100 MAP sensor is 2.5 bar, as well. It just shares the smaller diameter as the 3 bar MAP sensor, and hence will fit the Eurojet SMIC.

0Silva1 said:

(on a side note would it be beneficial to swap in a bigger MAP sensor on a chipped 5.9 Cummins or what is the Cummins equivalent of the MAP sensor)

Click to expand...

The MAP sensor tells the ECU how much boost you're running. The 2.5 bar MAP sensor reads atmospheric pressure (1 bar or 14.5 psi) PLUS boost of up to 1.5 bar or 21.8 psi. If you go above that boost level, the ECU has no way of telling how much boost you have, so you upgrade to the 3 bar MAP sensor to safely run higher boost levels.

If you don't get a remap the ECU assumes you have the stock MAP sensor, which reads 0.5 bar lower than the 3 bar. So...you have about 6-7 psi extra boost, which can break a stock VNT-15 pretty easily.

(At least this is how I believe this all works. Someone please correct me if I have this wrong!!! LOL )

Long story short, I wouldn't put a bigger MAP sensor on the Cummins without a remap, as the ECU likely will have wonky readings, and it may cause some potentially damaging overboost situations!