SamUK

iTrader: (1)

Can someone please explain to me the benefits of having a Knock Link fitted?

I already have a PowerFc, which I currently use for knock reading's.

How much can I be expected to pay for one?
Anything in particular I need to buy or look out for?

Or do i not need one at all....

Cheers
Sam

SamUK

iTrader: (1)

30+ views and no one knows...hmm...

Ok..where can i buy one from?

willy

Sam its a separate knock sensor fitted to the engine block.The display will give a varying degree of warning.
Its better than the factory knock sensor.
I had one before Andy F fitted my FC and he asked me to keep an eye on it whilst mapping.
Its just an extra precaution.

*****

ozzy

Use search m8, it's been done to death '00's of times.

Jap Innovations and BRD are two that'll supply one.

Houghton

iTrader: (1)

I have a Power FC too. It lights up the CEL when it detects excess knock. The CEL isn't particularly bright, whereas you shouldn't be driving if you don't see the RED at the end of the K/L display.

There have been group buys on here for K/Ls with prices about £125 iirc. LIke Ozzy said...you could try a search.

SamUK

iTrader: (1)

...had a look at Japinovations site..MRT Knocklink is £80

Cheers guys will do a search

SamUK

iTrader: (1)

Just had a chat with Brdevelopments....

£150+ delivery...not a nice chap to talk to must admit...i asked him about a group buy price...and this is what he had to say:

"we are the supplier's and you have to get our permission if you like to do a group by, and at the moment we are not allowing group buy's. If did allow it would be £130, so if you want to wait for a £20 saving you can"

Well, he answered my question...Knocklink display and sensor are required

Will keep an eye on the for sale section, missed out on one today..

Tone Loc

iTrader: (1)

LOL... you spoke to Branko then not Bob. Bit abrassive at times isn't he .

Personally i had a knocklink but when i fitted my Power FC i sold the knocklink. I keep the Apexi Commander permanently mounted in the car and mostly on monitor - 1 sensor and graph the knock value. I don't feel the need for the knocklink now but do agree it is far easier to see than when the CEL flashes.

Tony.

AndyC_772

iTrader: (2)

I wouldn't wait for the CEL to flash - the standard knock sensor just doesn't work that well, and there are plenty of reports of engines blowing up with no warning from the ECU at all.

I'd definitely recommend the KL; I had one fitted to my JDM STI despite it having a UK fuel remap. Up until last weekend I'd never seen more than a single flickering green light on it - then I refuelled the car and shortly afterward put my foot down and all 5 lights flickered on I've never backed off so fast in my life!

Without that warning - just a bad tank of fuel, I hope - my 3000-mile old engine could be an oily puddle of piston soup by now. As it is, I'm just taking it easy until this tank is used up - off boost it's fine.

highlander68k

Yes, that sounds like the other guy and not Bob. When I bought my Knocklink I nearly told him to shove it somewhere the sun doesn't shine. I wanted to buy it and was calling to order it. And nobody else seemed to sell it.

It was his lack of manners and his abrupt tone that gave me second thoughts.

There are others who sell it now.

willy

Its Branko, I think he gets taken all wrong...he is erm very direct.
Thats just his way LOL

*****

R5_GTT_Steve

iTrader: (7)

OK!!! i need help!! what the hell is the CEL light??? is it the engine check light?

And when do i need to fit a knocklink if at all? E.g after what mods? all im going to do to the car if a decat center and backbox plus a panel filter (for now) as the wife drives it alot more than me.

Tone Loc

iTrader: (1)

With FC Datalogit the CEL can be set to flash at any knock level (you do have to have a power FC and not OEM ecu tho ).... depending on the background noise level of the car. So it can be set far better and give more warning than the 'big red' on the KL.... but it's not as obvious due to it's dim light.

Not sure why you think the standard sensor doesn't work well.... its basically the same as the KL one! The problem lies with the ecu mostly. I can graph the output of the OEM sensor and it is very sensitive... rising immediately with any increase in engine speed and spikes are very obvious (on the graph)so you know it's det. Much harder to see what is engine noise and what is det on a KL display.


If you have both then fine, but personally i'd spend the money elsewhere..... as long as the FC Commander stays in the car.

Tony.

ozzy

Sam,

I've some info on the Knocklink on my website - http://www.stefanostadal.homedns.org....htm#knocklink

You need 3 parts.

1. Knocklink itself
2. Bosch sensor
3. connector kit

If you go seperately, then Jap Innovations will do it for £80 as you say. sensor can be had from any Bosch dealer for around £25-£30 and the connector kit is <£10.

If you use BRD they sell you all the bits together.

Don't know about the PowerFC, so whether you need it or not I can't say. There's loads on what the Knocklink does, but it's best to ask somebody like AndyF about the PowerFC.

Stefan

AndyC_772

iTrader: (2)

Fair enough - I'd heard it didn't work that well at high revs, and that the one that comes with the KL was better. Just recycling old information, Chinese Whispers style - as most do!

SamUK

iTrader: (1)

Guys thanks for all the info…

Im just having 2nd thoughts as I don’t really know how bad my car is knocking, though it feels like its getting rougher by the day!

I missed out on the knocklink that was for sale for £100 with the sensor as I did not know anything about it.

So will be reading up on the link cheers ozzy…

As for Jap-Inovations’- have had some bad experiences with them in the past, so prefer not to go there…

My CEL has only flashed once when I redlined the car by mistake, though that has never happened again..

When driving even slowly off boost, the powerFc knocks go up to 10, though when I accelerate and look at the powerfc, the knock bar seems to be constantly at 10 till I change gear…and if I need to spend another 100 odd quid then I will aslong as it puts my mind at ease…

If anyone knows anyone selling one can somebody please let me know...

Cheers

Tone Loc

iTrader: (1)

Do you know what knock is.... you say you don't know how bad you car is knocking though it feels rougher by the day. You won't feel knock at all (till the engine ****s itself if it is knocking badly ).

Going by the knock level you are getting on the commander (which is nothing) and that Andy mapped it (iirc) i'd say your car is NOT knocking. Keep an eye on the commander for any changes and spikes and you'll be ok. You would have been better off putting the money in the injectors and getting 550s instead of 440s IMHO.

Tony.

SamUK

iTrader: (1)

I just bought the 440's couple of months ago...and swore not to spend anymoer money on the car..as my aiming figures for power are near 330ish bhp...

Tone Loc

iTrader: (1)

LOL... the spending never stops. Personally if you were aiming for only 330 i wouldn't have bothered with the FMIC. FMIC and 550s (upwards) go hand in hand .

Tony.

SamUK

iTrader: (1)

If i could do it again...i would do it differently...

Not being married and living at home makes me spend my money on my car.. though i had to put a stop on it as a house and a wife are next on the list

bigsinky

don't foget that engine noise can show as knock. when i change gear at redline my knocklink lights up for a fraction of a second until the next gear is pulled.

Tone Loc

iTrader: (1)

LOL... already there mate . But now have a baby on the way too!!!!!!!

Tony.

willy

Sam just be careful buying a 2nd hand one as the knocklink boxes are not well made when new and can have poor solder joints.
Ps I modify the leds on extension leads to be remote mounted, so I`ve seen lots of the boxes and had 1 or 2 with poor connections.

*****

SamUK

iTrader: (1)

Congragulations...

Congragulations...

Personally i am dreding the day..but i am getting old, so my mum keeps saying .

scoobydood

Surely a knocklink is "insurance" even if you are able to get readings from the ECU side? It's an additional knock sensor and in a different location so if the stock one is faulty or doesn't pick up knock the k/l might... and visa versa.

Mine has been an engine saver.... But then again I don't have any way to read knock from the ECU so totally dependant on it

Tone Loc

iTrader: (1)

But what if both sensors were faulty... maybe three would be better? Insurance is good but you can go too far. The readings from the Apexi can be used to see if the sensor is faulty. You'd get normal everyday readings (backgound/engine noise) and if this differs for some reason then you can investigate. Also when the car is mapped i'd expect the mapper to use det cans, so the readings for Apexi can be calibarted as such. A knock noise of 25 is back ground noise, over 30 it can be considered knock etc.

Would anybody like to have two oil pressure gauges etc??

Tony.

SamUK

iTrader: (1)

My Knocks on the Powerfc have never gone above 15 usually, once did go to 45, but that was when i redlined it by mistake...

Though usually if i am knocking above 15, i play with the boost and the knocks then tend to register under 10.

ozzy

The main reason people fit knocklinks is because the std Subaru ECU doesn't do a great job under certain loads. It's been reported to ignore knock about 5000rpm for example.

Depends on the ECU IMHO. plenty of cars have detted and let go simply because the owner didn't know and the ECU couldn't cope. Question is whether the Apexi FC is far better at managing this. If it is then there's no need to install a knocklink. If it isn't then it's still valid.

The difference between an ECU knock correction and a knocklink is that the latter is always on display for the driver to see in real-time. Same with an Oil pressure or temp gauge. Since they're always on display it's easy to see how the perform under normal conditions. When they start mis-behaving it's easy to see that there's either a problem with the car or something's up with the gauge.

The problem I've always had with ECU's is they are hidden away and you can't see real-time data - unless you install some interface in the car of course.

That's my main argument for not requiring two visible gauges, but the benefits of having an external knock display rather than blindly relying on the ECU. But as I say it depends on the ECU. Don't know anything about the Apexi to comment on it's handling of knock.

Stefan

Tone Loc

iTrader: (1)

Stefan... that's the whole point, the Apexi shows in real time what the knock sensor is seeing (if the commander is installed). If find it far more useful than my old knocklink. That is what Sam has, so we are not talking about an OEM ecu. Also the Apexi has NO knock correction at all........ so you can not hope the ecu takes action, cos it won't.

Tony.