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-   -   Is me knocklink working correctly?? (https://www.scoobynet.com/general-technical-10/206268-is-me-knocklink-working-correctly.html)

Leeroy 06 May 2003 08:14 PM

Recently installed knocklink and associated sensor on MY97 UK turbo (max sensitivity). With the boost set at 18psi for testing purposes I get no lights at all under all conditions (except first green which is permanently lit). The sensor is mounted in the suggested position beneath the intercooler, and when the bolt which fastens it is tapped (quite hard) i do get the link responding accordingly. However, I would have expected some leds to be lit during full throttle and gear changes, so am a bit confused as to whether all is fine and if the readings are accurate.

Any help much appreciated.

Leeroy

Deep Singh 06 May 2003 09:25 PM

Leeroy when tapping the sensor are you getting all the lights up? If so then it should be working correctly.On some 'quiet' engines you see no lights.

Leeroy 06 May 2003 09:49 PM

Deep singh, yes I get all the lights up when tapping the sensor. Does this apparant lack of knock (and rich AFR under WOT) mean i'm free to tune further???!!
I think i'll turn the boost back up to 19psi and see what occurs.

I'm also a bit unsure of what to do next (MY97 decat d/p; p1 b/b; dawes; resonator removed; i/c water spray; 280Bhp @ 19psi), as i am under the impression that the TD04 turbo can't supply much more pressure (efficiently) than 20psi.
Would an uprated fuel pump help matters, as it seems as if fuel is being correctly supplied at present?

Great fun this tweaking malarky!

Leslie 07 May 2003 11:00 AM

I shouldn't worry too much Leeroy, Ive just fitted a Knocklink on my My 94 STI and it does not light anything up except occasionally one green flash if I really wind it up. You say you have one green on permanently, I have got the first green glowing very dimly when I switch the ignition on and can't explain that. If the engine lights that green it is very bright.

Les:)

RICH WILD 07 May 2003 11:02 AM

Leslie,

The green lights up dimly so you know you've got power to it. If a wire were to break or get disconnected by accident or something go wrong, you wouldn't know that the thing wasn't working until it was too late otherwise.:)

Cheers
Rich

Deep Singh 07 May 2003 07:08 PM

Leeroy,Rich would obviously be a good person to speak to.
Remember though it is not all about boost.Timing and fuelling make a huge difference especially on the road.A well set up Ecutek and the turbo mods Rich is talking about would yield fantastic results with probably lower boost(imho)

Leeroy 07 May 2003 08:40 PM

Thanks for the excellent responses.
Rich, I was under the impression that a top mounted intercooler wouldn't yield much of a gain, and was always reluctant to consider a fm due to possible torque reductions and the puny turbo I currently have.
What order did you carry out the listed mods?
You also seem to have quite a lot of MRT stuff, but did you purchase these direct or is there a UK supplier for these parts?
Also, what sort of a task is it to fit a TD05 unit, and did you notice any gain with this turbo at similar boost levels to the TD04 unit??
At what point did you uprate the fuel supply, I presume it was post TD05 to handle higher boost?

Thanks in advance,
Leeroy

p.s. Weren't you (and white turbo) in Banzai mag at Well Lane some time ago?

Leeroy 07 May 2003 08:41 PM

Deep Singh, is the Ecutek suitable for the MY97?

Turbo_Steve 07 May 2003 09:25 PM

Er.....if I tap mine I only get 2 or three lights, even on maximum sensitivity. Does this mean I've broken it aleady?


Hol 08 May 2003 08:36 AM

Mine only lights up the first light as a flicker at 4-4500rpm. but it does that whether on, or off boost which to me means engine noise rather than det.


RICH WILD 08 May 2003 10:10 AM

Hi Leeroy,

Wow! Quite a few questions! :)

I'll tackle them one at a time.

1)The reason I chose a top mount was that I already had a front mount on the white one and I wanted to try a different approach and keep the car looking more standard. (and yes that was me in Banzai - I'm in it again in June with the green MY97 ;)) The front mount allows much MORE flexibility in mapping and isn't THAT much more expensive than a top mount. The bad news is that unless you opt for PACE FMIC, you'll have to hack huge chunks off your bumper. You are probably right that your TD04 might be a bit lost with an FMIC, but if mapped properly you certainly shouldn't see torque LOSSES.

2)The order I carried out the mods was: exhaust (full decat), induction kit (tried a few before happy), lightened pulleys, boost controller and fcd. Ran sensible boost on the TD04 for a while (about 1.1.bar) then in readiness for the turbo, I swapped the fuel pump and fitted Lambdalink, Knocklink and electronic EGT Gauge. Car ran a bit rich for a week. Then did turbo and inlet pipe and finally top mount. Once that was done, I played with the boost a bit.:D

3)I use a lot of MRT stuff as my local specialist (Jap Innovations) is a UK MRT agent and I find their stuff to be top notch.

4)The TD05 is much laggier than the TD04, but I can comfortably run 1.4-1.5 bar on on it so, where the TD04 was running out of puff, this baby is singing. That suits my style of driving though. I'd rather get going first, being kind to the transmission, then welly it! The lag on the TD05 is mainly due to the limitations of the ECU with respect to fuel and ignition. My white car has a TD05 and a Link ECU and the boost comes in VERY quick. I have a bar of boost at 3000rpm. I've retained the HKS boost controller and let that run the boost and the Link do the fuel and ignition. Brings the boost in quicker, so I almost have the best of both worlds, quick spin up and big boost. This is helped even more as I have ultra short gearing on the white one, which cuts lag down.

4)The TD05 is a straight swap although you have to get the cover swapped on the TD05 for a straight entry, as the old cars with TD05s had 90 degree entry. The main advantage of the TD05 is that you can run more boost SAFELY. Bigger turbos run cooler at the same boost, as they don't have to work as hard, so less risk of detonation. The TD04 simply won't flow enough air to get you into the mid 300s, unless you absolutely work it to death.

5)ECUtek is for 99 onwards cars only. For 97-98 cars you'd need to go the Link/MOTEC etc. route which is £1000 + and more if you change the injectors. Don't get me wrong, it's worth every penny. The white car is MUCH quicker (356bhp, 348lsbft to the green one's 344 and 292) but it's whether or not you WANT to spend that on the car or not.

Bit long winded but hope that helps.

Turbo Steve,

Don't be timid, Give it a whack with a screwdriver handle. Not TOO hard, just build up gradually in force. You should be able to light ALL the lights.

Leslie 08 May 2003 12:12 PM

Rich

Thanks for the tip about the green light-did not get paperwork when it arrived. I enjoyed the info about your cars.

Les :)

Leeroy 08 May 2003 08:13 PM

Rich,
What a thorough response!

It's good to know what owners of the same MY have done, and you've certainly given me food for thought.
Up until I fitted the knocklink I was running 19-20psi (1.3bar) for quite some time without any problems (on two separate cars incidentally), and always found that the AFR was rich under wot (two green leds). With the knocklink fitted and with no led's showing (which I now know is working OK!) at 18psi, I assume that all is well with inlet charge temps and fuel mix. However, I do not drive on boost for significant periods of time nor do I do trackdays (not yet!), so it could be that during short blasts temps do not raise too much.
With my mix indicating rich it seems pointless to fit an uprated fuel pump/regulator as my next mod, so I am considering adding 1-2psi more boost (up to 20) to see what effect this has on AFR and knock.
However, if this is considered unrealistic for a td04 (and will result in flogging it to death as stated) i will have to be on the lookout for a td05 (anyone flogging one!?!).

Turbo Steve,
I too can confirm what Rich says, as it needs quite a bit of force to light all the leds.


Leeroy



Leeroy 08 May 2003 09:34 PM

ttt!

Turbo_Steve 08 May 2003 10:50 PM

well....have now tried wacking the engine with a 2 foot bar and still only get two lights....and that's if I do it right next to the knock sensor. So sumfing ain't right, as I believe they say.

RICH WILD 09 May 2003 09:09 AM

Hi Leeroy,

Like you say, I personally wouldn't run a TD04 much over 1.3 bar.
If as you say, you only boost for short periods, that's probably why you are getting away with it. If you were to run more boost on the standard intercooler and turbo for prolonged periods, I'm fairly sure you'd be seeing knock at some point, more so if you don't use octane booster.

I'd agree with you re the fuel pump, if the present one is coping, no point swappping, but with a bigger turbo, that may well change.

TD05s use to be 10 a penny, but now everyone has cottoned on to how good they are for cheap money, they are pretty scarce.

Try contacting Andy Forrest or Mark Aigin on here.

Steve,

try tapping the sensor itself, not the engine. Remember det is a big "eff off" explosion in the cylinder and you won't be able to replicate that by tapping the block.

Cheers

Rich


bwhinnen 09 May 2003 01:57 PM

Isn't the knock sensor also calibrated to a certain frequency range so knocking on the block may or may not simulate this freq?

I was a bit worried about mine when first installed, but soon learned that all the lights do work on occasion. I generally get one maybe two greens on full load runs, most activity happens on hot days (30+ degrees C) and during gear changes (transient det I believe Bob described it as).

Brett
MY00 (Aust Spec)

Leeroy 09 May 2003 09:14 PM

Rich,
I think i'll add 1psi and see how things go. As far as my next mod goes, do you think TD05 before top/front intercooler?

Is the TD05 turbo fitted to all pre-97 UK turbos as standard, and are there different inlet types (ie straight or curved)?

Cheers,
Leeroy.

p.s. I seem to remember knock generating 10 times the pressure of normal combustion, which is certainly a bigger bang than a screwdriver handle!!

Hol 10 May 2003 05:05 PM

I was told to tap the bolt head with a long half-inch socket extension. A screw driver just wasnt doing the job.

RICH WILD 12 May 2003 10:50 AM

Hi Leeroy,

Intercooler or turbo?

I'd personally go for the intercooler first. I know I did it the otherway round, but in hindsight the intercooler is probably the best mod to go for first, although changing to a bigger turbo and upgrading the intercooler should BOTh reduce inlet charge temps if you are running the same boost.

I'd say if you are fitting the turbo first, the temptation to whack the boost up may be too much, and I'd want a big intercooler there in case.

All pre 97 UKs came with the TD05 as did most of the WRXs. Some of the early WRX wagons had TD04s, but they ALL had 90 degree inlets. You can get a conversion to a front entry either by changing the cover (as the TD05 is used on other cars with front entry) or by cutting and welding your old cover yourself.

Cheers

Rich


MarkT 12 May 2003 12:45 PM

Excellent thread.
I have a PPP MY98 with the usual induction & exhaust mods.
Just fitted Knock link & I was concerned that I could only light up a couple of lights even when whacking it with a hammer, until I read this thread - it seems that's how they are.
Bloody hell detonation must be a big bang & surely very noticeable even without any flashing lights.
So 17-18 psi is about the limit on the TD04 - have tried this before but put it back down until I got a knock link - time to put it up again.
Anyone have any info specific to Prodrive ecu - good idea to turn boost up or not.
I have a Lambda link too but not fitted yet - couldn't find the right ecu wires.
Cheers
Mark.

RICH WILD 12 May 2003 04:04 PM

Hi,

This extract is taken from Maximum Boost by Corky Bell (sounds like an STD):D and is a damn good book about turbos:

"Detonation is the spontaneous combustion of the air/fuel mixture ahead of the flame front - combustion by explosion rather than by controlled burning. It occurs after the combustion process has started and is usually located in the last area to burn. As the flame front advances across the chamber, the pressure and thus the temperature in the remainig unburnt mixture rises. If the autoignition temperature is exceeded, this remaining mixture explodes. Detonation is extremely destructive. This is a result of temperatures that can reach 18000 degrees F in the centre of the explosion. The pressure spikes caused by the explosion can reach several thousand psi, and pressure rise is rapid enough to be considered an impact load. These temperatures and pressures are almost ten times higher than those accompanying controlled combustion"

Also consider that at 6000rpm, 50 explosions can occur in each combustion chamber in 1 second!

Cheers

Rich

MarkT 12 May 2003 04:22 PM

Therefore are we not saying that if your Knock Link lights up all the way - then some damage is probably already done.


Leeroy 12 May 2003 07:03 PM

Right, intercooler it is then!
Uprated top-mounts seem to vary quite a bit in price, but the MRT one does seem to be the largest out there, and hence is probably the most efficient. I imagine that the switch to a larger turbo will yield even greater gains using MRT's intercooler over the slightly smaller models.
I may well have to fit another nozzle to my waterspray to cope!

Cheers,
Leeroy

Hol 12 May 2003 08:25 PM

You seen the cheap prices of the Bare pace intercooler cores. About £75-80.

I wonder how much it would cost for an alloy welder to cut and shut the end caps off a standard top mount onto big thick double cor.

Just a thought for the day...

Leeroy 14 May 2003 08:21 PM

Is it a straightforward swap to uprated TMIC? I presume as long as the correct discharge pipe is fited (and associated parts) it should be fairly simple (compared to an FMIC anyway!!).

Leeroy.

Pogue 14 May 2003 10:34 PM

My knocklink lights up one green at 5000 rpm but when I went to 7000 rpm (just to see what it did for a couple of seconds) I managed to light up the yellows, is this normal?

bigsinky 15 May 2003 03:05 AM

@pogue

just sounds like engine noise to me. changing gear doesn't help either. as has been said b4 if you had det you would know it. i think it is safe to assume the it is just engine noise

cheers

big sinky

Hol 15 May 2003 07:55 AM

Pogue, does it light up at 5000 if you just rev the engine at the lights? Ie no boost?

Pogue 15 May 2003 10:20 AM

No, it only lights one green at 5000 rpm when moving.


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