93 wrx knock sensor?

[eliters]

as per title,do these have a knock sensor to adjust timing to engine load when pinking occurs?
just wondered as ive heard people talking of knock link which i assume to be basically the same thing?or is it just me/:blush:

[Scott.T]

There is a Knock sensor as standard but this will only retard the ignition as far as the ignition base map.
There is an ignition advance/correction map that the ECU runs, or tries to run, on top of the base map which adds on average 4 or 5 degrees (in the area concerned) on top of the base map.
If there is any det the igntion/correction advance values are halved, then halved again and again until no detonation is heard.

If det is still present at the base map, then the ignition cannot retard any more and hence it will continue to detonate.

The 'hot spot' for det is at full boost and 4,500 - 5,500rpm. This is were det would normally occur if there is too much boost, too lean a mixture (due to too much boost) or too much ignition advance.

If it's really bad the detonation will continue beyond 5,500rpm.

I've heard det (from inside the car by ear) both on my car and on a mates car during mapping and in both instances it was quite a loud single TINK noise as the revs passed thorugh 5,000rpm. This also tallied with the RED led flashing on the knocklink (The Knocklink is an additional after market knock sensor that provides an in cockpit LED display).

However, beyond 5,200rpm all was quite right up to the redline.

[eliters]

right so if i understand properly,the standard knock is ok,as long as you have a remap,and for big boost fit big inj/fmic,say 440cc inj?
or is a knock link essential?
dont mean to go on,but had a few cossies,main probs being the bottom end virtually everytime,but now got this wrx,and cant afford it to go pop as am out of work,plus dont really feel up to a self rebuild,as from memory(beetle engine) the flat 4 is a pig to work on,ie heads off pistons out etc.

[Scott.T]

You can run upto 1.1bar using the standard intercooler, standard injectors.
If you go above 1.1bar you need to think about injectors, intercooler and the map sensor (which max's out at 1.2bar).

Running 1.1bar without a chip/remap will probably cause detonation, as there is a high spot in the ignition correction map of WRX that needs taking out.
Plus 1.1bar is above the standard fuel cut limit of 0.95bar on a 1993 WRX.

Your ECU should be either a W6, U8 or a 2C (all 240ps). If it has a Z4 then it's out of the later 260ps post Sept 1994 WRX.

Also once you go above 1.1bar it's probably worth dropping an Apexi, GEMS or Motec ECU in. Which makes remapping alot easier to support future modifications.

The ECU in Pre99 Scoobs is fairly old clunky technology and tend not to have a nice laptop user interface for remapping.

You can add AVC-R, AFR and Fuel Cut defender apexi stuff to piggyback your standard ECU but these only fool the ECU and you end up with gadgets and wires all over the dash. Plus the cost of all these is more then the cost of an Apexi power FC ECU (which is around £400).

[eliters]

wicked ill check the ecu now and see what i find it is and if its chipped inside or not,watch this space....

[eliters]

hi its a u8 and it has a blank inside for a chip with 14 pins each side,also the j1 and l1 resistors are still intact.
so can i get a chip/remap for this?or is it better to get the apexi fc?i know you said a fc is around 400,so what should i pay for a remap and anyone you'd recommend to do it locally?

[Dyney]

Supplied and mapped I think Simon(Jolly Green Monster) does PFC's for about £700
If you intend to mod it further after the ECU is fitted I would go the PFC route.
If you just want a bit more poke and will be happy (yeah right :rolleyes:) then go for the chip :)

[eliters]

wicked,will prob have to just settle for a chip tbh at the min as am unemployed so 700 isnt an option,so do you know what i should pay for a remap?cheers.