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I'm after some collective tomes of wisdom here, 'cos I'm trying to get my head round what's going wrong with my turbo set up. This gets a bit heavy and involved, so please bear with me!
The background:
I was running an Abbott ECU with MBC that saw me get up to 290hp. I'd decided that I wanted to "comfortably" push through 300hp, and that the route to go had to be software. About the same time, my turbo was starting to smoke, so I upgraded it to a T3/T28 roller bearing hybrid rated for 350hp. I first fitted this and noticed an increase in lag at the top end- not surprising though.
I then ordered new software, which arrived and was installed. There was a problem with it, so it went back and the ECU was apparently checked out and set up on another car (in Sweden) then returned to me.
Things were looking good, lots of
but the peak boost crept up to about 2 bar. I was also getting the occasional instance of it holding base boost for a while then suddenly rising up, so I suspected perhaps I had a faulty APC solenoid.
On the rolling road, peak power and torque were down on the expected by 30 or so horses & lbft. I sent details of the session off to the software folk who said that there was a terrible boost spiek (true- the max should only be 1.65 bar apparently) and thaty it was not holding up boost high enough at the top end to reach the maximum power.
Last night I fitetd a new APC solenoid, and briefly saw a peak of nearly 2.3 bar
before the pressure blew the hose of the intake manifold.
The tuners say this is happening because the spool up time of the roller bearing turbo is too quick once it gets going. I'm struggling to see why this should be the case and why the APC doesn't stop it.
I poped my old Abbott ECU back on last night for comparison and that performed as expected.
Now, apparently the standard MAP sensor only maps to about 1.6 bar. In the equivalent kit that the tuners supply for my level of tuning, they include a 3 bar MAP sensor. They said I didn't need it, just the software and bigger injectors. When I queried it, they said the 3 bar MAP sensor is only there to enable them to map a fuel cutoff at 1.95 bar. However, I thought information from the MAP sensor was critical to APC- without it, how can it know how much to open/close the solenoid?? Or is the operation of the APC vakve controlled by other parameters like info from the DI cartridge , knock sensor etc.
Which I suppose is the nub of my query: How does Trionic APC work?
Anyone got any (sensible
)thoughts?
Thanks
Mark
The background:
I was running an Abbott ECU with MBC that saw me get up to 290hp. I'd decided that I wanted to "comfortably" push through 300hp, and that the route to go had to be software. About the same time, my turbo was starting to smoke, so I upgraded it to a T3/T28 roller bearing hybrid rated for 350hp. I first fitted this and noticed an increase in lag at the top end- not surprising though.
I then ordered new software, which arrived and was installed. There was a problem with it, so it went back and the ECU was apparently checked out and set up on another car (in Sweden) then returned to me.
Things were looking good, lots of

On the rolling road, peak power and torque were down on the expected by 30 or so horses & lbft. I sent details of the session off to the software folk who said that there was a terrible boost spiek (true- the max should only be 1.65 bar apparently) and thaty it was not holding up boost high enough at the top end to reach the maximum power.
Last night I fitetd a new APC solenoid, and briefly saw a peak of nearly 2.3 bar

The tuners say this is happening because the spool up time of the roller bearing turbo is too quick once it gets going. I'm struggling to see why this should be the case and why the APC doesn't stop it.
I poped my old Abbott ECU back on last night for comparison and that performed as expected.
Now, apparently the standard MAP sensor only maps to about 1.6 bar. In the equivalent kit that the tuners supply for my level of tuning, they include a 3 bar MAP sensor. They said I didn't need it, just the software and bigger injectors. When I queried it, they said the 3 bar MAP sensor is only there to enable them to map a fuel cutoff at 1.95 bar. However, I thought information from the MAP sensor was critical to APC- without it, how can it know how much to open/close the solenoid?? Or is the operation of the APC vakve controlled by other parameters like info from the DI cartridge , knock sensor etc.
Which I suppose is the nub of my query: How does Trionic APC work?
Anyone got any (sensible

Thanks
Mark