Hi All,

I have a standard 94 WRX. I am looking into doing some 'improvements' on my car over the next few months.

I have been reading all the FAQs about and all the various posts here.

What is the recommended way to get reliable power increases. I have heard about the Superchip, PE (?), Motec and UniChip.

I understand that the Superchip is a one-off, i.e. unmappable. The PE system can be remapped again and again as you add oher mods. The Motec is just too expensive (for now) and the UniChip is similar to the PE system but actual widget sits alongside the standard ECU rather than inside.

Think I have that all correct.

So, I have discounted the Superchip on its lack of features (remappable) and the Motec on cost (over four figures).

The UniChip can be fitted for 450 ukpounds plus setting-up. How much is the PE system fitted ? Is the PE system like the UniChip in respect that you have to go back to the rolling road to have it remapped ? Or can you tweak the PE system with your own laptop ?

Sorry for all the questions, but I'm new here ;-)

Cheers

Lee

 

Hi Lee, Lee here

The superchip on its own does NOTHING! All it does is remove the safety cut-out feature of the engine..when 16psi is reached for a second or two the engine should cut the fuel. Obviously we would like to increase the boost above 16psi so the superchip removes this engine protection. It does this by telling the ECU that it is only seeing 15psi when in fact 17psi is being produced. Therefore the ECU (being sent duff info) sends back duff info for fuelling and ignition. Bang. A lot of companies wont sell a superchips for the impreza. Plus like I said the chip does nothing on its own..you need to increase the boost via a bleed valve (£25 crude) or an electronic boost controller (£300 plus). Pricey and risky.

The motec is a completely new engine management system and is programmed to suit your car. Some would say the best, but at a cost.

The PE is the standard ECU hardware, but the software is reprogrammed to suit your car. Boost/fuelling/ignition etc is changed without any adverse effects. IMHO the best option unless you have a MY99/00 where it is not available YET ! (David..grrrr)

Not heard of the Unichip.

Graham Goode also do a "chip" I think this falls between superchip and PE..it is a replacement chip but not modelled on your car therefore may be suspect. I know of a place that rolling-roaded it, but had to abort since the car was pinking badly.

There is a thing called PossumLink which is a new management system that you program yourself. Unless you are a ECU whizz or can afford a new engine best left alone !

Oh plus theres probably a prodrive conversion.

For your car..PE PE PE me thinks. £695 plus VAT I remember. They need your car for the day. Best fit any filters/exhausts before mapping.

(phew)

 

Lee (and Lee),

I think the Superchips "upgrade" consists of the module that fools the map sensor AND a bleed valve, so the package does increase boost, but NOT safely.

The PE phase one is £650 + VAT. I have driven cars with the conversion and can thoroughly recommend it.

Have a look at

 

Hi All,

Thanks for that one. Only downside I can see on the PE system is that although it is hidden away, you cannot easily return the car to stock form.

For those who don't know, the Dastek Unichip, is a piggyback ECU. You splice into the loom and program maps into the system with a laptop. You basically add/subtract numbers from the base maps to make your changes. It modifies the signals going to and from the stock ECU. Beauty is you can easily remove the system and return the car to stock.

I can't belive you haven't heard of it. It is quite big in the Nissan GTI-R and Toyota GT4 area.

You say that Power Engineering need your car for the day (just checked out their site). Can you hang about, give a hand, see your car on the rolling road etc. ? I know some places don't let you watch/help. I'm always think not letting you watch your own car being worked on is a bit sus. ;-)

OK, jury is still out. I will do some further research and let you guys know what I decide. At the moment, the Unichip wins as it is 200 squid cheaper and as far as I can see does the same job as the PE system. (ish).

Cheers

Lee S.

 

PE are happy for you to watch, don't know about "helping" though When I had mine done I just got a courtesy car though BMW 750, power yes performance no.
Why would you want to revert to stock ECU/mapping? AFAIK the PE remap is invisible to anyone (except the driver ) including when plugged into the Select monitor at Subaru Garages.

 

Hi guys..

As stated above there are several different systems, ranging from:

Signal clamp (and bleed valve) - Superchip
Fuel/Ign remap - PE
Complete ECU - Motec, Link, Haltech, Autronics, HKS, Apexi, Syms
Piggy back - Unichip, Icon, HKS

The link is very good and is reasonably priced....it comes with preset maps...but these normally need tweaking to get the most from your car (and you need to know about mapping).

For simplicity go the PE route if you dont want any hassle...

Do they keep charging you 650 each time you go for a remap after the first time ?

HKS is good...but expensive....

Depends on your budget..and your future plans....

My belief is wait..and get the mapping done last after all the other mods...(assuming you can do that). Its pointless spending 650 and the time to have a map...then go and change some stuff...only to require another remap.

J.

ps - Bugger..Did I just recommend PE..oops

 

Hi guys...

The part about having a "generic" upgrade.. that can be removed and refitted to a new car is a good idea.... Its what I've got... and when I come to change my car.. I will keep the bits for the new one (you loose too much on upgrades), it works out better to keep them.

Unichip is big...but not over here...

Its true with the PE system that its another chip.. not that straight forward.... but it wont work in any other car... chances are it wont even work in another scoob .. they fine tune it exactly to that car... *i believe*

I have yet worked with Link... but its features and technical support and R&D program seem to be great... If I hadnt gone HKS, chances are I would have chosen Link...

Ask my mate Bobby-boy Rawle about the Link system..

The MAP is changed to cope with pressure.. not sensitivity...

I know on earlier cars you had to cut a link to activiate the second socket.. but you can simply resolder/reqire the link...

J.

ps - The new really good/cool thing is the Apexi Super-AFC... it looks great..and works.. and is about 450 quid... Its using the piggy-back concept...it allows fuel to be increased/decreased at set RPM ranges.... it uses AFM... Revs and throttle...I know guy running it... he has just fitted it.. I'll keep an eye out and see how he gets on..

[This message has been edited by firefox (edited 19-10-1999).]

 

Hi All,

The plot thickens.

The PE system seems to be the recommended way to go for the Scooby. But hey, I never follow the crowd ;-)

I change cars every few years and I like to take my mods with me, hence wanting to be able to return the car to stock (as much as possible).

So the PE system is 650 + VAT and mapping time for each remap, I guess is around 50 an hour.

The Unichip is 450 + VAT and mapping time for each remap is about 50 an hour.

Mmmm, decisions, decisions.

I think I will go for the Unichip. If anybody is interested in the results, let me know. I plan to have it fitted later this week.

Cheers

Lee S

 

Before you do...

have you actually spoken to PE ?

I believe their way of doing things is to plug an external EPROM into a slot on the ECU package - remove the EPROM and a stock car again. No splicing of wires etc etc.

Plenty of people here have had a PE conversion..don't know of anyone who's had a Unichip !

PE sometimes change the MAP sensor as well cos the std subaru one is not sensitive enough..again, more reason to choose PE.

I don't have anything to do with PE, all I am saying is that others experience has shown that they are knowledgeable about the Impreza, have a good product and its in use out there !

 

Isn't the Apexi Super-AFC just the same thing as the HKS Vein Pressure Controller? Anyway, yet another ECU upgrade alternative is the Mine's VX-ROM. I don't know if it's available in the UK, though.

 

Switching to a re-mapped Jap board/ecu, is iffy to say the least.Remember they use 100RON fuel, and increasing the boost, and advancing the ignition on our cars, with our fuel, is going to end in tears !!!.

Stick to a product that can be re-mapped/adjusted over here.Getting it set up for 95RON would be easier, and cheaper to run, without very much loss of power.

PE, Link, etc', can all do this.

Mark.

 

Hi All,

Right, that it is it. I am more confused than when I started ;-) Thanks to all who have helped.

I have booked my WRX into PowerStation in Cheltenham to have the Unichip fitted. I lied about the cost earlier. It is 500 + VAT *including* setup. Thereafter, if you require a change of map (new exhaust, water injection etc.) it is 50 an hour.

The Unichip can also be used to drive water injection, extra injector etc. All things I may do in the future. Oh, and it can removed and put on my next car (probably another scooby) and remapped.

No disrespect to PE and their kit but I kind of like the versatility of the Unichip.

Power figures just as soon as it is all fitted.

Cheers

Lee S.

 

You would be doing us all (and Powerstation) a great service if you could get printouts of the bhp/torque charts before AND after the conversion.

Then we can get them mounted in Paul Strong's dyno hall-o-fame.

If you havent got a scanner, no worries cos I have !

cheers
lee.

 

Well seeing as the subject is already running, I will stick my oar in.

I have just had my chip changed from a 'K Series' (not off of a rover), chip to a Blitz chip. (It actually has 2 chips).

The previous one was allowing the car to boost over 1.8bar without hitting a safety limit, this new chip has overboost protection at 1.2bar but I can only induce it with a 4th gear heavy load, roll on.

Devastatingly fast.

However, I have been following the lead set by some of the more switched on technical guys on the BBS and I am going to fit a Possum Link.

Had a look at all the others and ruled them out for one reason or another.

I am now relatively happy that my engine is running as well as its control equipment will allow it to.

PE dyno day....... I don't think I can wait that long, I will go down before then and have it ran up to see what it is doing.

Possum Link guarantees needing to spend loads of time fine tuning for the best power/torque and drivability.

Oh No! Not more time spent playing with my car!

Mike.