Pfc Overboost Protection

[Don Dada]

Can someone tell me how does the overboost protection on a pfc equipped with a boost control kit works?

I know it will do some sort of saftey cut when boost goes over target by 0.25kg/cm2, but does it just drop back boost by varing the duty cycle of the solenoid itself or does it do an internal fuel or ign cut?

[GTSBoy]

I don't know for sure, but the whole point of such protection is to protect against a loss of boost control. So using the boost control gear that is not working (and hence allowed the overboost) is not smart. Therefore I would expect it to be an ignition cut, like the original ECU.

[STATUS]

hard fuel cut from memory, on the last supra i tested it on.

[Dose Pipe Sutututu]

Wonder if this is a myth, I played around with my old boost kit on the PowerFC and the boost spike like +0.5 bar when I played around with the duty cycles, no cut there at all.

I had the boost set at 1 bar, with a pretty high duty cycle of around 60. In 2nd gear, the boost spike to like 1.45 bar and nothing

[STATUS]

  On 17/06/2011 at 12:35 AM, johnnilicte said:

Wonder if this is a myth, I played around with my old boost kit on the PowerFC and the boost spike like +0.5 bar when I played around with the duty cycles, no cut there at all.

I had the boost set at 1 bar, with a pretty high duty cycle of around 60. In 2nd gear, the boost spike to like 1.45 bar and nothing

Definately works but its often glitchy some of the supra (map based) pfc's false cut even if there is no pfc boost control kit fitted... you need to input 2.0bar on the boost settings tabs.

[jiffo]

No myth John.

You were going the wrong way if you wanted to test it out.

Set your boost way low, say 0.4 bar then give it a try.

The turbo will easily/quickly boost over approx 0.7 bar and you'll then experience the cut.

(Cut occurs if actual boost exceeds set boost by >0.25kg/cm3)

At normal boost settings, you'll rarely see the cut.

  On 17/06/2011 at 12:35 AM, johnnilicte said:

Wonder if this is a myth, I played around with my old boost kit on the PowerFC and the boost spike like +0.5 bar when I played around with the duty cycles, no cut there at all.

I had the boost set at 1 bar, with a pretty high duty cycle of around 60. In 2nd gear, the boost spike to like 1.45 bar and nothing

[Dose Pipe Sutututu]

interesting, wait till I get another car, I'll try it out again

[JonnoHR31]

  On 17/06/2011 at 12:05 AM, STATUS said:

hard fuel cut from memory, on the last supra i tested it on.

this, cuts all fuel on all normal pfc's, not sure if it cuts ignition on pros but i doubt it

[Don Dada]

Nice.....

Will see how my little experiment goes......

[Don Dada]

Yea...tested it and confirmed its a HARD fuel cut at 0.25kg/cm2 over the set target boost.

Can someone tell me if the the 2 wire harness for the boost control solenoid comes off the main engine harness(gtr) or if it comes off the wiring some where else in the engine bay??....I

[89CAL]

In the gtst it is cut and shut to the stock harness for the stock boost solenoid. Not sure on a GTR but. It is in Paul's PFC FAQ somewhere

[STATUS]

  On 21/06/2011 at 5:10 PM, Don Dada said:

Yea...tested it and confirmed its a HARD fuel cut at 0.25kg/cm2 over the set target boost.

Can someone tell me if the the 2 wire harness for the boost control solenoid comes off the main engine harness(gtr) or if it comes off the wiring some where else in the engine bay??....I

factory boost solenoid wiring.

[limpus]

  On 17/06/2011 at 12:05 AM, STATUS said:

hard fuel cut from memory, on the last supra i tested it on.

Trent...is this something new? When my car was tuned you said all you could do was set the maps so that if it goes into the dangerzone it would overfuel and pull all timing out...

[STATUS]

  On 22/06/2011 at 5:20 AM, limpus said:

Trent...is this something new? When my car was tuned you said all you could do was set the maps so that if it goes into the dangerzone it would overfuel and pull all timing out...

were you using the pfc boost controller? i thought you had an avcr?

[paulr33]

im using PFC boost kit and have been for a while

very happy with it and works well

set and forget

and has bonus of simplistic safety cut instaed of unlimited boost

also when you use the boost kit by default boost correction is enabled in the powerfc

from memory it has boost correction for airtemp (GTR only) and low water temp (from memory it runs less boost on cold water)

[Don Dada]

  On 21/06/2011 at 11:48 PM, 89CAL said:

In the gtst it is cut and shut to the stock harness for the stock boost solenoid. Not sure on a GTR but. It is in Paul's PFC FAQ somewhere

Yes gtr is the same

  On 22/06/2011 at 3:35 AM, STATUS said:

factory boost solenoid wiring.

Cant find it Its a rb26 ...but not in a gtr

I dont think its on the main enigine harness tho, ie. the one that goes into the plastic rail along the intake side cam cover, but it has to link back to the ecu somehow obviously to get control on the solenoid

[paulr33]

no its on the main harness

on the GTST it is wire 25

check this on the GTR

from memory its the same