PowerFC monitored values - how safe?

[rs73]

Hi man,

I've been looking at peak figures on my HC and done a bit of search but can't find any info on the forum.

On city driving with ocassionla zippy accel and mix of traffic jams, my

Knock level tops out at 10, and water temp at 81C

Car is running HKS EVC@12psi,

FMIC,

stock injectors,

Bosch pump,

3" exhaust system,

tuned to 188.5rwkw (normal, NOT shootout) on Optimax.

1) Are those knock level sounds ok? That happen on fast acceleration with gear change around 4500rpm only. What's the knock level to start getting worry?

2) What's the maximum safe water temp? is 81C safe? At this temp reading on my HC, the needle on my factory water temp gauge is sitting halfway.

[Morgs]

10 knock? You're laughing, thats fine.

81C is OK.

[rs73]

Glad to hear it's ok...

Still some part of my questions haven't been answered yet...

What's the maximum safe knock level for RB25 that I should watch out for? 20? 30?

What's the maximum water temp to be considered safe? 100C?

Also one more thing, I noted the AFM voltage hovers around 1200-1300milliVolt

on idle... I thought the max stock AFM voltage is 1.5V (1500mV?) or 5V (5000mV)?

I remmeber reading it somewhere on this forum... but can't remember

[Sydneykid]

Glad to hear it's ok...  

Still some part of my questions haven't been answered yet...

1. hat's the maximum safe knock level for RB25 that I should watch out for? 20? 30?

2. What's the maximum water temp to be considered safe? 100C?

3. Also one more thing, I noted the AFM voltage hovers around 1200-1300milliVolt

on idle... I thought the max stock AFM voltage is 1.5V (1500mV?) or 5V (5000mV)?  

I remmeber reading it somewhere on this forum... but can't remember

My suggestions;

1. The dash warning is usually set around 40 or so

2. 85 degrees C is usually considered to be the target water temp for maximum power. Anything up to 105 degrees is not unusual, but around 80 to 90 is where it should run.

3. Max AFM voltage is ~5.1 volts

[shonen]

Im not sure about the 33s but for the 34s the dash light comes on once knock reaches above 60.

10 is hardly anything to be worried about.

[rs73]

Thank's SK, great input as always :-)

Shonen, on the R34, is that setting above 60 on a stock ECU, or a default setting on PowerFC for R34?

[R31Nismoid]

Im not sure about the 33s but for the 34s the dash light comes on once knock reaches above 60.

10 is hardly anything to be worried about.

if thats PFC your talking i think its adjustable

81 water temp is great in traffic

[rs73]

My suggestions;

3. Max AFM voltage is ~5.1 volts

Punting it around furthermore I saw my top AFM voltage is 4.3volts.

So that's about 84.3% capacity at around 11 or 12 psi boost.

So using that as a rough guide is it correct to say that my AFM

would probably max out at about 14psi?

Injectors are only up to about 43% though.... so injectors still got some more life in it....

[Robo's]

Thats very safe, im seeing 80-90 knock and in the 90's injector cycle.

[Beer Baron]

80-90 knock doesn't sound too good.

[SLY33]

oooh robos 80-90 knock, id be going back to the tuner and get some timing pulled or something! im happy with my tune if i dont see over 30 knock... at the moment after a full on thrash i get about 28, and occasionally a 30.

as far as 10 knock is concerned, i think if let out a good fart when driving i might see that

[Chris32]

I reckon the knock read out is differant for every car, more of a guide than a measuring tool

Mine is all over the shop sometimes, I think my sensor is stuffed, either that or my exhaust or something hits the bottom of the car now and then and it picks that up. I remember when I was getting it tuned for a street meet ages ago, we pulled almost 6 degrees timing becasue the knock light was flashing, dropped 50rwkw, and it would still register knock. Coming back up slowly on the timing, we found it could take another 4 degree's (10 degrees above the minus 6) before it did knock, and let out a bit of a puff of unburnt fuel out the back, and the knock value stayed the same.

So I reckon its more of a guide than a measuring device, either that or mine is rooted!

That said, it has been quite handy on occasions, can tell the differance in knock levels when its got shit fuel in it, but there are greater things at play I think with my car....... something is making noise and it aint detonation!

[INASNT]

On RB25 the check engine light also comes on at around 60 knock on the pfc.

I sometimes get a higher knock reading (40) during slow traffic jam driving than I do on the track with 7000rpm changes :confused:

[Robo's]

Some times i get knock going upto 40 driving to the shops below 3000rpm. I also got 28 starting it up this morning, ouch

I might get a bit of knock and i always monitor it, but i've never heard it ping. I used to hear it ping with the stock cooler setup , but then i had no power FC to monitor the knock.

[paulr33]

rs73 if you run to redline in say 3rd gear youll go near 5.001 volts on the airflow meter

[Sol32]

Power FC nub question here, my knock value isnt shown by a number, just a bar - how do i get it to show an actual figure? Thanks in advance.

Andrew

[benm]

Haven't used my hand controller in a while but you press either the up button or the back button 1 of the 2 and it changes the display.

[GTshortie]

If its just showing a Bar on the h/c , press:

UP to see Peak/highest value reach(the knock will be a number then)

RIGHT to reset

DOWN to return to monitoring again without peak / highest values

[Guilt-Toy]

The engine light can flash for 3 difference scenario's

1: knock going above the previously set level (setup on PFC laptop software)

2: The AFM voltage gets maxed out or close to maxing out

3: Injector duty goes higher then the set amount.

Usually the knocking is a very quick flash but this is programable within the Apexi power FC software. When dyno tuning i was told (from a mate who owns the dyno) he said to set the knock level when tuning to 40 and tune the car to show no more knock then that then set the warning to 60 so that the engine light flash's at 60 then he tells the owner of the car to back off the accelerator if he gets the warning light flashing - that way you know that knock is getting to a higher level for whatever reason and that something could be wrong....

If you get slow flash's of the engine light then usually it could be because the injector duty is maxing out (do a log max of the injector duty) or the AFM voltage is getting maxed out (you can log that as well in monitor)

Its hard to explain but say your tuner tunes the car to go to 90% duty cycle on the dyno and the car only runs 18psi of boost and he sets your injector warning to go off at 96% - your on a full on 4th gear hit in the freezing cold weather your turbo spools to 22psi - that would mean that the tune would go to a lower part of the map.. I know on my tune i changed the numbers that go lower on the map to a richer / fatter tune with less timing because IF the turbo spools enough load to go to those area's its going to need to run richer (or it may still be OK at the same numbers but you cant be sure because you have not tested it) - this area may go over the 96% injector duty that the warning was set to which will make the lights go off - it can also be running in a state where its very lean and can cause your engine to go kaboom! if you tune your car to go say 5psi higher then you plan on driving it on the street and set the warnings to go off at around those levels then you know its a bit more safer - thats the difference between a $200 touch and go power up tune compared to a $600 - $1000 tune where they pay attention to detail - you could save 3 hours of dyno time and not cost as much but you never know how good the tune actually is.

The same goes for the AFM voltage - if the map gets to the last line on the map then your going to get the warning because its maxed out - you could be only running 1psi more and its all OK or you could be running 10psi more which can cause issues. Some people run standard RB25 AFM's and tune the cars to run huge power levels and just tune the last line to run good safe mixtures to the maximum boost your boost controller is set to (never done it myself and dont know much at all about doing it this way as ive got a 90mm V8 AFM and at 16psi i still got more room on my load maps) this could be bad because you have to switch off the AFM warning. so next question is what happens if you get a big boost spike ? your answer is as good as anyones... (i aint 100% sure about this last comment as i have never done it that way before)

If your tuner uses the power FC software you can tell him to disable the warning for injector duty and AFM warnings all together so the engine light will only flash on knock to remove confusion because i know as well as as anyone when your on full noise you are trying to keep the car in a straight line and notice the light but dont pay attention to how its flashing as it could result in a accident or something...

So yeah when it comes to warning lights you need to totally understand how the power FC works and which warning you are seeing.

I guess it just pays to pay someone good decent money for a tune that you know that all these scenario's have been taken care for just for piece of mind - i spent 6 hours road tuning my car and when i put it on the dyno I was pretty impressed with how it was done.

hope this helps

[NYTSKY]

sorry to hijack.Looking at my inj cycle im seeing 95-97% at full throttle.Would you say its time for some 555cc's?