for each of the different pulley kits? And might anyone know the max boost the computer will let you run before bad things happen?

 

I have a 181mm pulley and threw a P0108 Max Absolute Pressure error this weekend at the race track. The boost hit 20psi according to the frame data.(70.87inHg)

 

With my 178 asp pulley I have seen 18 psi. I have at least 300 passes at the track with no check engine lights.

 

i was under the impression you would get a boost code somewhere between 21 and 22 b/c i think we have a 1.5bar MAP sensor stock

 

is there a map sensor upgrade so we can put more boost without tripping a error code or have the timing pulled or anything? that is if our engine can handle it

 

no one to my knowledge has done it. maybe a map clamp?

see post 607
https://www.crossfireforum.org/forum...tml#post334813

post 715
https://www.crossfireforum.org/forum...tml#post395759

 

Map Clamps ,Bleed Off Valves, and Pressure Regulators have been used on the PowerStroke Diesles for years.
The Map Clamp is easy to do.
This is how it is done on the Powerstroke...
1. Find the highest voltage from the map sensor that the car is getting full fueling.
2. Find the lowest voltage from the map sensor that the car is setting the overboost code.
3. find a Zener Diode that is between the voltages of step one and two.
4. Attach one end of the zener diode to ground.
5. Splice the other end of the zener diode to the map senor wire going to the ECM.

This would make the signal voltage look like this if the zener diode was set at 4.7volts...
0 psi boost = 1v
10 psi boost = 1.9v
15 psi boost = 3.8v
20 psi boost = 4.5v All Voltage are made up for this example!!!
21 psi boost = 4.7v
22 psi boost = 4.7v
26 psi boost = 4.7v

Hopefully this is not to confusing.
Downside is that we do not know the voltages of the map sensor and unknown about how it will effect the ecu and programming. Might not even work for our model.

The Boost Bleed Off Valve is what I use on my truck.
This little guy attaches inline with a "T" between the boost source and the Map sensor. It has a tiny needle valve and bleeds off all pressure above the spring pressure of the needle valve. It does not bleed off any noticeable boost pressure from the engine. It only bleeds off over boost on the line. After installed...

1. You have for example 30psi coming from engine source to the "T".
2. You have for example 22psi coming from the "T" to the map sensor.

and/or

1. You have for example 10psi coming from engine source to the "T".
2. You have for example 10psi coming from the "T" to the map sensor.

Downside is that it look like it would be hard to make work in our motors. The Powerstroke map sensor has a easy to cut line to put the "T" in going from the engine to map sensor.

The Boost Pressure Regulator is just what it says. It is a shop air pressure regulator adjusted to the proper psi. It works much the same way as the bleed off valve, but is spliced inline between the engine and map.
1. You have for example 30psi coming from engine source to the splice.
2. You have for example 22psi coming from the splice to the map sensor.

and/or

1. You have for example 10psi coming from engine source to the splice.
2. You have for example 10psi coming from the splice to the map sensor.

The downside of the regulator is the same as the bleed off valve, it is harder to install and make work. The other difference is that there is not any boost pressure (although super small) getting released. One downside is some people have had problems with a pressure wave affect causing weird effects. I think those are from less quality regulators. Some regulator are made for 100+psi and do not work as well at 15-25 range. So regulator needs to be for the proper range.

I am adding some picture links... I hope I get this right.

Map Clamp... Not much to see. hehe
http://www.spdiesel.com/dOBE/fOBEproduct.jpg

Boost Bleed Off Valve...
http://www.dieselsite.com/ProductImages/brvoldnew.gif

Boost Pressure Regulator...
http://www.itpdiesel.com/images/products/280_image.jpg

 

Are you useing one of these examples or might anyone els on there Crossfire?

 

Using higher rail fuel pressure, I have hit 25 psig, no code cause the f/a was reasonable at the time. Probably not good to go that Hi, your just probing the break something zone. 20 should be enough for anyone with a street car. Woody

 

None of my post on boost limiting has been tried on a Crossfire as far as I know. All Voltages are made up from my head and All boost numbers are made up from my head for example purposes only. I am just making a statement about how it is done on the PowerStroke diesels. I DO use and know that all these examples work on the PowerStroke Diesel. Real data for Crossfires has not been pulled yet. No test for the Crossfire has been done. Anyone with the time and knowledge is more than welcome to pick up the title and run with it. I am not going to be able to.


I am personally with Woody on this... 20 psi should be good for any average street car. This mod would be for more the Turbo, Drag Race, and Extreme guys.

I also believe that Programing enhancement and understanding is more needed before we go pushing further with boost and stuff. As Woody has already pointed out and started to address there is fueling problems that need to be taken care of before you add more pressure and air. Just a thought.

 

how much boost has the 178 and c/3 combo been known to make?