Post by: teamgeorge on November 04, 2008, 04:29:26
a picture would be appreciated
is it 6psi/7psi stock (like jap cars) then turned up around 18-19psi i've read around here?...
Post by: nizzkid on November 04, 2008, 05:29:26
Post by: ouri30 on November 04, 2008, 05:42:55
Turbo in CRDi is controlled by a range of sensors that feed info to the ECU, so we have been led to believe. I assume you have read the threads about reprogramming the ECU (Martin from DW Tuning). From what I have gathered, reprogramming the ECU, or using a box like Shambles has installed, is the best way to change the boost / fuel delivery and to gain more power.
I have fitted a Scanguage and can see the MAP (Manifold Air Pressure) as I drive. MAP can be as high as 30+ psi when it needs to be (just plant your foot and the respose is evident), but it sits as low as 14.8 psi when idling. I have also noticed that a 2-3 psi gain is evident when the aircon is operating. This small boost in the MAP compensates for the A/C operating. There may also be a change in fuel pressure / delivery tha I am not aware of.
Now, the turbo is variable vain and is, I assume, controlled by the ECU and the range of sensors, including the throttle. So, what I gather is that the ECU delivers the precise amount of boost and the correct fuel ratio for the job at hand. Messing with this balance is not something I would want to play with.
I reckon the best results would be had by either using an after market chip or a DW Tuning type reprogramming.
Just my thoughts. Others may have differing opinions or variations on the theme.
Bob
Post by: Lakes on November 04, 2008, 09:24:56
what Shambles has got seems to be the best value for $ and does not change the boost pressure and at around $200 AU its hard to beat. also easy to fit and easy to remove.
Post by: teamgeorge on November 06, 2008, 01:42:47
if Shambles is only $200 AUD i will look into that... it needs to be posted from europe though? what website was it?
Post by: ozsnowman on November 06, 2008, 04:31:50
Quote from: "ouri30"
I have also noticed that a 2-3 psi gain is evident when the aircon is operating. This small boost in the MAP compensates for the A/C operating. There may also be a change in fuel pressure / delivery tha I am not aware of.
I was wondering what happened when I put the air-con on. Numerous times I've switched it on, and kep an eye of the rev counter - I've noticed no apparent drop of performance as the compressor kicks in, and rev's are unchanged. That answers a lot of my questions, thanks mate!
Post by: Lakes on November 06, 2008, 09:13:42
Quote from: "ozsnowman"
ozsnowman i never notice a loss in power or Tq with my v8 or with the 6 i had b4 that, but with some 4 cylinder petrols i have owned in the past i could feel them struggle when i turned aircond on. but the company toyota is 4 cylinder petrol and i can't notice that struggle with air cond on. but when i had the scangauge like bob i noticed how the boost went up if i was in 5th at around 1,600 going up a hill it would raise the boost i think it is done by lowering the manifold vacume as this changes the variable vane to cause it to boost more as the vacume goes up it lets the vanes go back then the center screw in the turbo takes over for revs.Quote from: "ouri30"I have also noticed that a 2-3 psi gain is evident when the aircon is operating. This small boost in the MAP compensates for the A/C operating. There may also be a change in fuel pressure / delivery tha I am not aware of.
I was wondering what happened when I put the air-con on. Numerous times I've switched it on, and kep an eye of the rev counter - I've noticed no apparent drop of performance as the compressor kicks in, and rev's are unchanged. That answers a lot of my questions, thanks mate!