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Knock reading on your PFC ??

subzero

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what kinda numbers are you reading on your Power FC ... ive been keeping an eye on mine as of late after ever spin , just seeing what its max reading shows at ....

just today it hit 17 ?? dunno if thats good or bad , just thought it was good to get some feedback from a few others.

bearing in mind im only boost at .7 bar . have it mapped for 1 . but when im tipping round the place i leave it at .7
 
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StarletRick

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this is the one reason i would never run a PFC...

they do nothing about knock. they just let it happen even if its getting worse.
 
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StarletRick

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stock at the moment.

but when i go standalone, ill use hks fcon vpro. its the best thing ever. if it had tits, i would marry it.
 

subzero

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the FC seems to be extremely popular which is why i trusted it ., isn't hks just a piggy back after all.
 
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StarletRick

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hks isnt a piggy. it runs along side your ecu to run the engine, while it leaves other stuff (AC for example) to the stock ecu.

pfc's are popular coz they are quite tunable, and are fairly cheap. they are great if tuned right but to get a proper bulletproof tune they need alot of road hours with a tuner.

they are closed loop systems, which will never be as good as an open one, even with all the tuning in the world. they just dont do anything about knock. they will detect it, and flash lights at you, but the ecu itself wont change anything about the engine to try to correct it. even stock ecus retard ignition timing it it detects knock.

thats why they take so long to tune, you have to get them ready for everyt scenario. if the conditions are different (humidity, heat, etc) than when you had it tuned, it wont be running as good as it could be.

they follow the map blindly without adjusting anything if it needs tweeking.

i know loads of people have good results with them, but i personally wouldnt use them.
 
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I would'nt say the pfc does nothing to prevent knock.

PFC is set by default to give you a engine warning light when you hit 60 or over on the knock. So it up to you to momitor your engine light and choose to egnore or not. the warning can also be switched off.
also give warning light for injector duty cycle too.

generally anything close to 60 or over would be concidered bad knock.

the most knock i ever get on my pfc is about 26.
 
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I would love to run a HKS management, but sadly we dont have the qualified people over here in ireland to tune HKS management. so it is pretty much limited to what your tuner can do.

I've also heard Nistune stuff are quiet good. they can also retard ignition timing if it detects knock. We do have someone over here that can tune them:thumbs: he is also the same guy that road mapped my car and did a pretty good job of it too.
 

sniffy

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i think the highest mine has read is 24 and it set to flash if the knock hits 30 im running pfc.
 
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hks isnt a piggy. it runs along side your ecu to run the engine, while it leaves other stuff (AC for example) to the stock ecu.

pfc's are popular coz they are quite tunable, and are fairly cheap. they are great if tuned right but to get a proper bulletproof tune they need alot of road hours with a tuner.

they are closed loop systems, which will never be as good as an open one, even with all the tuning in the world. they just dont do anything about knock. they will detect it, and flash lights at you, but the ecu itself wont change anything about the engine to try to correct it. even stock ecus retard ignition timing it it detects knock.

thats why they take so long to tune, you have to get them ready for everyt scenario. if the conditions are different (humidity, heat, etc) than when you had it tuned, it wont be running as good as it could be.

they follow the map blindly without adjusting anything if it needs tweeking.

i know loads of people have good results with them, but i personally wouldnt use them.
Rubbish, the Power FC is the closest aftermarket computer to the stock item but with far more adjustable parameters. Thats why they have been so popular. The only thing that they won't run is the imobiliser(NATS)

It doesn't take that long to tune and the reasons people get caught up in the "knock levels" is because it is easy to monitor on the hand controller and they can see something that they were never able to see.

Iv'e had mine successfully tuned for years

Do you know what knock levels are present on a stock computer?

What readings do they get to before they retard them?

Power FC is still hooked up to your engine warning light.

SR's are fairly agricultural engines. The knock sensor is basically a microphone in the engine that picks up other noise's besides detonation.

All SR's have knock readings and after speaking to SR experts knock readings(spikes) of up to 100 are still acceptable.

I have a mate who tracks his car regularly and has had high readings with no ill effect.

Any computer will give you knock readings, its the tune that determines if they are safe,not the brand of computer
 
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cbarry

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power fc

i agree with auss15.i had power fc in my old 180sx the knock often went over 100,car was mapped by tdp which might explain it also,brought it back up to tdp couldnt find problem.but car drove good never gave trouble.but subzero ive heard anything over knock level of 40 was bad.
just after buying power fc for my s15:D
 
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StarletRick

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it isnt rubbish, its fact. the PowerFC is a closed loop ECU. it will never be as good as an open loop unit.

im not saying they are awful ecus. the huge number of cars that run great figures proves they are very tunable. but they are still closed loop.

they do not compensate for knock, at all. end of story.

i would never have one, as i dont want something that is blindly following what its told, regardless of whats going on. i would never 100% trust it. you can get a vpro for the same money and they are a better ecu in my opinion. they wont give different power figures if tuned the same, as they are both very mappable. however, the vpro thinks for itself if the conditions fall outside of those that the ecu is mapped for, the PFC doesnt.
 
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subzero

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just one question starletrick ... the hks unit has no commander obviously , how do you know what knock levels your at ? your trusting the unit to do its thing really ?
 
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StarletRick

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instead of buying a £250 PFC commander. i used a £100 knock-link, which is fantastic.
 
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StarletRick

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not from new mate. commander is seperate from the ecu when bought new.

knock link still worked perfectly though.
 

subzero

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not from new mate. commander is seperate from the ecu when bought new.

knock link still worked perfectly though.
:confused: i bought mine new from nengun , came with commander and harness for my car . worked out cheaper than a 2nd hand hks fc pro which was for sale locally at the time.
 

meddler

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the only PFC's that came without the hand commander were the pro or AP engineering ones AFAIK.
 
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it isnt rubbish, its fact. the PowerFC is a closed loop ECU. it will never be as good as an open loop unit.

im not saying they are awful ecus. the huge number of cars that run great figures proves they are very tunable. but they are still closed loop.

they do not compensate for knock, at all. end of story.

i would never have one, as i dont want something that is blindly following what its told, regardless of whats going on. i would never 100% trust it. you can get a vpro for the same money and they are a better ecu in my opinion. they wont give different power figures if tuned the same, as they are both very mappable. however, the vpro thinks for itself if the conditions fall outside of those that the ecu is mapped for, the PFC doesnt.
HUH, the Power FC starts the car as a open loop PC, then as it gets up to operating temperature it goes to closed loop.

A closed loop PC is more efficient than a open loop, as it interfaces with the O2 sensor and AFM. It makes adjustments to AFR's while monitoring injectors and temperature changes. They are far easier to tune and offer performance and fuel economy.
To say it blindly just follows is rubbish, as it uses all factory sensors to run the car with stock efficiency.

Open loop systems require more tunning and, in fact are not as efficient as they don't use O2 sensor or AFM's. If you want to run monster power then yeah, but the car probably won't have many stock parts on it.
They are more sensitive to air temp changes and fuel economy.
You might as well stick a carby on your car.
 
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