6K or Z4 ECU, whats best?
 

as above. whats best for my MY93 wrx jdm? fancy upgrading my standard one and just want to know whats the best to go for? thanks.

Dont bother, just get a polar peformance chip.

well i can get hold of these for half the price of a polar chip so i thought i'd see what people thought. both will raise the boost right? then when i have more cash i could add the performance chip?

z4 is 260 bhp. 6k is 280 bhp both run on v power or tescos 99 ron only .

thank you. and the 6k should have a space for an additional chip later on?

hi mate id stick with the z4 which is more suited to your car then get the polar performance chip at a later date the 6k was out of a v2 sti

ive tried the 6k ecu in my 93 wrx just recently but had trouble with boost and the engine management light stayed on when fitted , it was a lot quicker but bit unreliable .
but in the last week i have had my standard ecu polar chiped and it far better than the 6k loads more boost really clean power comes in real strong and hold boost all the way to about 7200 rpm. cost me £95 plus i got him to fit it and that was £50 all through his site on ebay.
reaaly mate i would go straight for the polar performace upgrade !!
another thing my 6k didnt have the the solder joints empty so it would have had to have been resoldered, some have the space some dont.
and for price youll pay upto £100 for a 6k , 7k , z4 or z5 anyway.
go for the polar they are s**t hot

6k is 275ps BUT myself and a few others have had trouble running them in the early wrxs.
https://www.scoobynet.com/scoobynet-...ml#post8643541

the z4 can be run on 97 ron the 6k should be run on 99 ron fuel.

sorry for butting in here but just a quick question , do you run yours on 97 ron ?

polar says after mod that they can be run on 97 but i am still going for the shell 99 v power !!


myblackwrx you done anymore modds on yours yet !

sorry for butting inn:norty:

Although i can run it on 97 the avaliability in my area is very poor only 99 SUL is avaliable so i stick with that the only place i've seen selling 97 the price is the same as 99.

On the mod front i'm hopefully buying a later model STI RA or Type R :) as spending more money on my car i think would be a waste imo.

ive tried both and the z4 is nowhere near as good as the 6k

the z4 is a nice safe map with the benifit of an upgrade over the standard u8 or w6 ecu. 260 instead of 240 ps. ive never witnessed a 6k running 100% so i cant advise on that one. the polar chip will plug into any pre 96 ecu and give about 280 ps. i personally would go for the z4. if your engine and cooling system is well maintained/healthy the polar chip is great.

deffo Z4 i had one in my 93 wrx with a scooby chip (as known back then) from scott taylor (now polar perf.)& it ran fantastic & ran on 97-99 ron fuel with no issues what so ever.
Top guy scott & its a great map

:wonder: Why didnt you just chip your standard ECU? The effect would have been exactly the same. The map on the scooby chip replaced that on the Z4 anyway.

It isnt worth getting a Z4 IMO. I hardly noticed any difference and would just save up for the polar performance option if I did it again.

Just out of interest I swapped out a D7 for a Z4 but hardly any noticeable gains (according to my Right foot anyway!.. not Dyno'ed the Car..)

I have a near standard Classic 96 UK Turbo... what are the gains for the Z4 over the D7 normally and if I were to get one of them Polar chipped which one is best to have altered.

Scoobyspanners it doesn't matter which one you get altered as the chip runs car.
The Z4 has a better fuelling map compared to the early ecus and holds boost to redline whereas the early ones wouldn't.
I found the power increase negligible but the drive a lot smoother.

I have a z4 ecu if anyone is interested £50 delivered

my 93 import came over with a z4 ecu in it, so mr japanese owner before must have put it in! i then had the scooby chip (as i wanted to run uk fuel) & had the boost raised also knowing that the map/chip & engine worked well together from my research as it was only a standard wrx so no forged internals etc, i also had HKS induction& cold feed, hks downpipe, afterburner vortex system, lightweigh pulleys, organic clutch & l/weight flywheel & walbro uprated fuel pump etc etc etc. Had it r.roaded at a place in stockport & it ran 317bhp & 321 lbs. dont ask me how but it did! & ran like a dream & pulled like a train in every gear. So it must have done something to get that power from a car that standard was 240bhp with original ecu

However i did go through 6 clutches & 3 gearboxes :rolleyes: & from the extra power it highlighted the aged coil packs so had to renew them.

bargain! :thumb:

Hi dont mean to hijack, but are there polar chips worthwhile looking at? They seem cheap for some easy gains, are there not chances of det etc even when run on super unleaded due to it not being specifically matched for the car? It just seems to good to be true when the alternative is a 500 live map from the likes of andy c?

exactly my thoughts mate, i bought a 6k and had my standard spare and talked to scott and he told me the new chip overides it so just sell the 6k.

it runs brilliant with the polar:thumb:

i think you'll only get to around 320 bhp with it and mods then you'll have to run an adjustable map, live map , but for the money polar are superb and until you can afford at least £500 there well worth it:)

Thanks for the reply! Will look into getting my spare D7 ECU chipped...

heres his ebay details

SUBARU IMPREZA - ECU UPGRADE (1992-1996 WRX/STi & UK) on eBay, also Chips, Performance Tuning Parts, Car Tuning Styling, Cars, Parts Vehicles (end time 13-May-09 20:08:36 BST)

cheers carl