My 250+HP CRD build

flash7210 · **Posted:** Tue Oct 20, 2015 8:46 am

diesel_guy86 wrote:

2) I had my injectors extrude honed ~30% or about 50hp worth. This is how I am making 260hp on the 200hp hot tune from GDE.

How did you go about getting the extrude hone?
What shop does this kind of service?

flash7210 · **Posted:** Tue Oct 20, 2015 9:06 am

diesel_guy86 wrote:

3) A map sensor reads from a perfect vacuum. 1 bar of pressure is 14.7psi, or the pressure at sea level. So if you have a 2.5 bar sensor, subtract 1 bar of pressure and that means you have 1.5 bar of pressure left, or 21-22psi. A 3.5 bar sensor will mean the computer will be able to read up to 35.75psi of boost.

Yes, you correct about the MAP sensor BAR/psi calculation.

Have you tried using the Bosch 0 281 002 845 sensor?
I think its a 3 BAR sensor.
Some here are already using it on stock engines.

mass-hole · **Posted:** Tue Oct 20, 2015 11:06 am

flash7210 wrote:

diesel_guy86 wrote:

3) A map sensor reads from a perfect vacuum. 1 bar of pressure is 14.7psi, or the pressure at sea level. So if you have a 2.5 bar sensor, subtract 1 bar of pressure and that means you have 1.5 bar of pressure left, or 21-22psi. A 3.5 bar sensor will mean the computer will be able to read up to 35.75psi of boost.

Yes, you correct about the MAP sensor BAR/psi calculation.

Have you tried using the Bosch 0 281 002 845 sensor?
I think its a 3 BAR sensor.
Some here are already using it on stock engines.

If you go by that thread, both the stock sensor and 845 sensor are 3 bar which should give us up to 28.8 psig.

Here is the official Bosch brochure for our stock sensor: http://www.finjector.com/verkkokauppa/documents/5226302185a2a/0281002437.pdf which says it reads to 300kPa or 43.5 psia. So if we are only able to see up to ~20 psi from the ECU then its a tuning issue, not the sensor.

You should crank the boost up with your resistor so you are at like 25psi and then really quickly cut it to see if the MAP spikes above 20-21 psi.

diesel_guy86 · **Posted:** Tue Oct 20, 2015 9:18 pm

I'll have to check and see what MAP sensor the jeep has now, but the one I have on the shelf is a 0-281-002-456.

I can peg my 30 psi boost gauge and the torque pro app shows me only getting 21psi.

The 3 bar sensor will only read to 29psi.

I took my injectors to my local injection shop, whether they did them or sent them out I don't know. But any injection shop should be able to help ya.

mass-hole · **Posted:** Thu Oct 29, 2015 1:01 pm

Just thought I'd throw this out there, but Yeti just posted that the pre-05 Cherokee 2.8L in Europe used a wastegated turbo. I wondered if maybe they had a different exhaust flange and sure enough:

http://www.ebay.ie/itm/JEEP-CHEROKEE-KJ-2-8-CRD-Exhaust-Manifold-WITH-WARRANTY-/171776685478?hash=item27feb035a6:m:mefe5rumkjID7Oaklaeiwlw

I dont know what it is but it seems to be a more standardized fitting than what we have on ours. The closest I have seen is CT25 or TD05

diesel_guy86 · **Posted:** Sat Oct 31, 2015 9:09 pm

Wow great find!! I think with the turbo that far back it will be really close to the firewall. Maybe too close for a downpipe? My 3" dp barely clears now.

That bolt pattern looks like a Mitsubishi pattern, I'll have to research tho.

mass-hole · **Posted:** Mon Nov 23, 2015 2:08 pm

So I have an experimental tune loaded up to my jeep that allows 2600 mbar or around 23 psi (even up here at 6500' asl). I have been doing a lot of experimenting with the tunes and I have been able to eliminate the altitude associated boost limiter and also adjusted the boost map to the 2600 mbar limit. I was going to see if my MAP hit a cap somewhere above 21 psi. I have tried a few tunes with the boost limiter remover and boost map set to 2400 mbar(20.1psi), which is a bit higher than the factory of 2335, and have seen a few excursions above that during quick accelerations and have not seen the MAP hit a ceiling. Anyways, hopefully my turbo wont explode and I can report back in a little bit on what happens.

FYI, I run a daily driver tune with the boost limiter set up to limit boost to around 2200 mbar at altitude so I am not driving around at 2400 mbar all day everyday.

mass-hole · **Posted:** Mon Nov 23, 2015 6:21 pm

mass-hole wrote:

So I have an experimental tune loaded up to my jeep that allows 2600 mbar or around 23 psi (even up here at 6500' asl). I have been doing a lot of experimenting with the tunes and I have been able to eliminate the altitude associated boost limiter and also adjusted the boost map to the 2600 mbar limit. I was going to see if my MAP hit a cap somewhere above 21 psi. I have tried a few tunes with the boost limiter remover and boost map set to 2400 mbar(20.1psi), which is a bit higher than the factory of 2335, and have seen a few excursions above that during quick accelerations and have not seen the MAP hit a ceiling. Anyways, hopefully my turbo wont explode and I can report back in a little bit on what happens.

FYI, I run a daily driver tune with the boost limiter set up to limit boost to around 2200 mbar at altitude so I am not driving around at 2400 mbar all day everyday.

So I was able to see 2550 mbar(22.3 psi) in my torque logs. On the live readouts in torque i did see it spike to 2590(22.8 psi) once but that didnt get captured in the log for some reason. The turbo would not sustain above 2510 mbar so anything above that was just a brief spike.

So we should be able to see above 21 psi. Diesel_guy, I wonder if you need to swap your MAP.

mass-hole · **Posted:** Wed Nov 25, 2015 4:44 pm

mass-hole wrote:

So I have an experimental tune loaded up to my jeep that allows 2600 mbar or around 23 psi (even up here at 6500' asl). I have been doing a lot of experimenting with the tunes and I have been able to eliminate the altitude associated boost limiter and also adjusted the boost map to the 2600 mbar limit. I was going to see if my MAP hit a cap somewhere above 21 psi. I have tried a few tunes with the boost limiter remover and boost map set to 2400 mbar(20.1psi), which is a bit higher than the factory of 2335, and have seen a few excursions above that during quick accelerations and have not seen the MAP hit a ceiling. Anyways, hopefully my turbo wont explode and I can report back in a little bit on what happens.

FYI, I run a daily driver tune with the boost limiter set up to limit boost to around 2200 mbar at altitude so I am not driving around at 2400 mbar all day everyday.

So I was able to see 2550 mbar(22.3 psi) in my torque logs. On the live readouts in torque i did see it spike to 2590(22.8 psi) once but that didnt get captured in the log for some reason. The turbo would not sustain above 2510 mbar so anything above that was just a brief spike.

So we should be able to see above 21 psi. Diesel_guy, I wonder if you need to swap your MAP.

Whoops, there was another boost limiter I forgot to increase, that's why it would go beyond 2500 mbar. Will try again.

mass-hole · **Posted:** Thu Nov 26, 2015 1:33 pm

mass-hole wrote:

So I have an experimental tune loaded up to my jeep that allows 2600 mbar or around 23 psi (even up here at 6500' asl). I have been doing a lot of experimenting with the tunes and I have been able to eliminate the altitude associated boost limiter and also adjusted the boost map to the 2600 mbar limit. I was going to see if my MAP hit a cap somewhere above 21 psi. I have tried a few tunes with the boost limiter remover and boost map set to 2400 mbar(20.1psi), which is a bit higher than the factory of 2335, and have seen a few excursions above that during quick accelerations and have not seen the MAP hit a ceiling. Anyways, hopefully my turbo wont explode and I can report back in a little bit on what happens.

FYI, I run a daily driver tune with the boost limiter set up to limit boost to around 2200 mbar at altitude so I am not driving around at 2400 mbar all day everyday.

So I was able to see 2550 mbar(22.3 psi) in my torque logs. On the live readouts in torque i did see it spike to 2590(22.8 psi) once but that didnt get captured in the log for some reason. The turbo would not sustain above 2510 mbar so anything above that was just a brief spike.

So we should be able to see above 21 psi. Diesel_guy, I wonder if you need to swap your MAP.

Whoops, there was another boost limiter I forgot to increase, that's why it would go beyond 2500 mbar. Will try again.

Tested my new tune on the way to the gas station to get milk that we forgot for thanksgiving. 2550mbar is the max torque will out put. It hit 2550 mbar and then just sat there.

happy thanksgiving

flash7210 · **Posted:** Thu Nov 26, 2015 2:34 pm

I know the turbo is capable of more than 23 psi.
The limitation is either the MAP sensor or the ECU.

The MAP sensor only puts out a 0-4.5 volt signal
The volt/mbar value depends on the sensor calibration.
But the ECU also needs to be programmed according to the sensor calibration.

Yeti · **Posted:** Thu Nov 26, 2015 3:56 pm

try to increase the map that start at 0F7180 I think is the MAP sensor limiter , in my with stock value the kpa reading do not surpass the 225 kpa , but if I increase this map the Kpa reading increase
at this address 0F708A there is a bit at 2300 , is the real turbo limiter
and at this address 0F70B8 is air temp / boost limiter ...........but I think is not useful for this situation

hope this help

mass-hole · **Posted:** Fri Nov 27, 2015 11:06 pm

flash7210 wrote:

I know the turbo is capable of more than 23 psi.
The limitation is either the MAP sensor or the ECU.

The MAP sensor only puts out a 0-4.5 volt signal
The volt/mbar value depends on the sensor calibration.
But the ECU also needs to be programmed according to the sensor calibration.

I have been doing more research and I believe the 2550 mbar may actually be a limitation of the OBD-II PID for manifold pressure and thus Torque itself is the issue.

If you read here: https://en.wikipedia.org/wiki/OBD-II_PIDs#Mode_01 It states that the Intake Manifold Pressure PID has a range of 0 to 255 kPa, or 2550 mbar. That seems mighty coincidental. I also stumbled across a Mitsubishi Evo thread that stated they have the same exact issue. Guys are tuned to make 26+ psi yet torque will only show them 22.3 psi. I believe it has to do with the fact that the PID is only assigned one byte of data, which is 256 bits. 0 to 255 is 256 individual numbers.

I wonder if the ECU itself can see above that but we cannot see it via OBD. I don't know how you can get around this though since every reader is going to be looking via obd. The MAP scaling should just be a simple Y=MX+B equation because its linear so it doesnt make sense that it would have a cap in the tune. If you look at the PDF i linked before they show you the scaling for our OEM sensor and its a dead straight line.

mass-hole · **Posted:** Thu Jul 07, 2016 7:30 pm

diesel_guy86 wrote:

Wow great find!! I think with the turbo that far back it will be really close to the firewall. Maybe too close for a downpipe? My 3" dp barely clears now.

That bolt pattern looks like a Mitsubishi pattern, I'll have to research tho.

Does your 2863 use a GTX compressor wheel or is it a custom job from KPA?

diesel_guy86 · **Posted:** Thu Jul 07, 2016 9:29 pm

Its a billet machined wheel. The gtx wheels have 11 full blades, they are great for making boost at low psi, but at high boost the full blades get in the way of each other. They arent able to take a "full bite" like the normal 6 full + 6 short (also known as 6+6, gtx wheels are 11+0) wheels.

My 250+HP CRD build

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