ric

Hello Scoobydrivers,

I wanted to fit a VF23 to my car together with an Unichip. But this isn't possible as the standard MAF sensor of the car isn't able to measure such a big amount of air.

How could I solve this problem?

It seems to be well known that the MAF sensor of this car isn't very good.

I think the problem could be solved by fitting a Link, but I live in Switzerland and to fit and map the Link I would have to drive to UK to have it mapped.

thanks for any answers/informations/suggestions
ric from Switzerland

Hyperex

Change to a Skyline GTR (modify a bit) or STI version 3 (running VF-23 as standard turbo) maf sensor.

ric

Is that possible?

A change without a problem?

greetings
ric

njc

No problem, this is not as complicated as you thought. Order from subaru or find a second hand ones will be good as gold. After fitting, reset ECU.

[This message has been edited by njc (edited 19 June 2001).]

JeremyJones

I noticed recently quite a few people talking about various difficulties in making the Unichip work in a number of different cars/engines. For a long time everyone was extremely positive about this "cheap" solution although its limitations were known all along.

I also notice that Unichip is often used with less than totally capable boost controllers. If a proper electronic boost controller is applied, the package does not really cost that much (if at all) less than other 100% programmable options.

Why so few Unichips (if any? I am not sure) on Phase II engines?

I am seriously contemplating another ecu, etc. and wonder if there is something else one would need to know.

thanks a lot in advance
Jeremy

RobJenks

Ric,
Dump the Unichip and get the Link.
I have recently installed a VF22 and have remapped the Link accordingly.
If you want assistance in mapping , there are plenty of great members on this BBS who can provide the right support.

ric

Hyperex, njc: Are you sure that this could solve my problem. Can the UK-MY98 ECU read and use the data of the better MAF sensor?

Is it just the sensor that is limited or is it also the ECU?

greetings
ric

ric

Rob

Thanks for your answer. The problem is that here in Switzerland there isn't a mapper for the Link. And I don't think that I could do it myself. So I would have to drive to UK to have the Link fitted and mapped. So Unichip is the only real option I have, otherwise I would have to drive a lot of kms!

off topic: I see you're from Perth (Australia). Are there a lot of nice Scooby owners? I will be there from August till October to "upgrade" my English. Would be nice to have a ride in a Scooby!

greetings
ric

Hyperex

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by ric:
<B>Hyperex, njc: Are you sure that this could solve my problem. Can the UK-MY98 ECU read and use the data of the better MAF sensor?

Is it just the sensor that is limited or is it also the ECU?

greetings
ric[/quote]

Guess you are getting serious in this... ok, i got to be serious too. First of all, what model and version is your car? What turbo is your car running? What after market parts have you changed. How can you be sure that your maf is not able to run with the vf-22? Please answer all the questions as it relates to how accurately of assistance i can provide, hate to mislead anyone... Also, i have made a post in other thread, i now paste it here in since i think its kind of relevant to your case.

----------- ---------- -----------
After market chip always provide higher boost pressure than stardard. Always know what boost pressure the car is currently running (by adding a boost guage) and check with the chip supplier how much boost it should read after installing the chip, say the uk wrx is running at 1 bar, after installing the chip can expect something like 1.1 or 1.2 bar. In comparison, it is better to have it chiped rather than just boost controller as the mapping of fuel, timing and boost data are all changed in one package. Therefore if the car have already the chip thus boost controller is not too important, unless for fine tune purposes as result of boost various on some car. So if the chip have 90 to 95% accuracy, i would say its consider matching data. I would check with the supplier whether the program is best goes with which sort of mod because it is usually chiped for changed of exhaust and air intake. The best way is to have something like Motec, Autronics, Link, this sort of multi mapping programmable computer which have to be set up by professional with laptop on road and dyno for optimum result, boost controller won't be necessary since it comes with external device for boost adjustment. (thanks Adam )
----------- ---------- -------------

Off course, everybody have different point of view therefore anybody who is reading this are welcome to correct me if felt otherwise.
cheers...

[This message has been edited by Hyperex (edited 19 June 2001).]

[This message has been edited by Hyperex (edited 19 June 2001).]

IWatkins

Ric,

I don't see the problem. There are plenty of cars (not just Scoobies) running bigger/hybrid turbos on the Unichip and using MAF or AFM's.

Ask your Unichip tuner to have another look at the MAF on your car.

Cheers

Ian

Adam M

Hyperex,

i dont understand why you need to use a boost controller with an autronics, motec or link, when they have programmable boost .

I also agree with Ian , I know of plenty cars uk cars running non standard turbos (including the higher flowing vf22) running on a unichip.

I didn't know you needed to change the MAF sensor.

Hyperex

Adam,

Yes you are right, totally agree with you. Oppss.... have mixed up with the system i had now (HKS F-Con V pro), yes yes, totally agree with you, thanks for correcting me. I will edit my post so won't mis-lead others.
As for maf sensor, guess you have misunderstood me, i didn't meant the maf have to be changed at all, just want people to make sure their maf can take that extra flow after filter changed (for pre-caution only), this is why i asked Ric in my post asking him why is he so sure that the maf can't run with the vf-22? His machanic said so or he is just guessing?

Thanks and appriciate your feedback, seen your post very often but this is first time we communicate directly name to name.

cheers.

Adam M

jeremy jones,

if you are considering another ecu, might I suggest going to speak to brdevelopments.

They sell motecs which are great pieves of kit and both Bob and Branko are very nice people, or perhaps you know them already?

Hyperex,

didnt mean to appear to be correcting you, dont have any hands on knowledge of mapping or ecus, I was questioning my own understanding not yours.

You are right in that I did misunderstand on the MAF sensor thing. I did think you were suggesting fitting an alternative part. My mistake, sorry.

nice to speak directly to you too.

Hyperex

How to upload pictures to BBS. Anybody help?

[This message has been edited by Hyperex (edited 20 June 2001).]

JeremyJones

Adam,

thanks for the recommendation. I realise BR Developments are one of the few companies that seem to make cars go better without losing engines or similar disasters. I don't really think Motec is something for my car (not being an STI of some kind), but Link could be the way to go. I will send Bob an email and see what he has to suggest.

On the subject of the MAF sensor and VF23 I am not sure why ric thinks it cannot handle the slightly larger amount of air when compared to the TD04 or a VF28 as on STI cars. It is known than none of the fully programmable ecus do not use the factory fitted MAF sensor anyway. Is Unichip using it?

Jeremy

Rich_R

Ric

Not sure if the MAF on a MY98 differs from a MY00

I'm running a Unichip, Hybrid VF22, Water Injection and HKS EVC IV boost controller on a UK MY00 using the standard MAF

Got a remap today after recently having the hybrid turbo fitted and also re-performed the learning setup on the EVC - car is now just right. Very pleased with the RR figures at PS too. FMIC next week so may raise boost from 1.15 to 1.2 Bar.

IMHO don't consider a Unichip without a decent boost controller - the EVC is great on the road (had one or two problems on track which I'm looking into). Only issue for me with the EVC is that it holds the programmed boost all the way to the red line. There are alternative boost controllers out there which allow you to set boost for a number of RPM sites and thereby allow you to lower boost at high revs for safety. I guess that this is only really an issue running very high boost.

Either way I would speak to both Rich at Power Station and Bob at BR Developments first before making a decision.

Rich

Adam M

Doesnt the uni chip operate by foling the standard ecu? which would mean that it does employ the maf sensor.

I dont know anything about this inability to handle more air thing, I wold be interested to know where that came from.

My car runs a standard ecu, until my new motec arrives, and also a vf23. I could check the part numbers, but from the outside my MAF sensor looks identical to every other one I have seen.

Can someone confirm also if the standard turbo on the sti 3 is a vf 23, because I didnt think it was.

EvilBevel

Think there is some confusion here ... as far as I know, what Mark Verhoeven (guy that Ric talked to) is saying is that there is indeed a difference between a MY98 and MY99/00 (phase II) engine (including MAF sensor). He has developped a kit (Unichip + boost controller + hosing + spark plugs + VF23) that was extensively tested on MY99/00 engines, and he would have to redo a lot of the work for a MY98 to be on the safe side.

The standard ECU (which you still rely on very much with the Unichip) needs a 100 % working MAF sensor, and I think what Mark is afraid for is that with higher boost (1.25 bar) and a VF23, the readings will be off, so fuelling needs to be redone/adjust more completely.

He does not have the experience that for example PS would have with the Unichip: we pretty much had to find out from scratch how things worked on my MY99. It took us about 10 sessions over a 4 month period to get everything right, and it now takes 2 full days for him to fit the kit / adjust to the individual car. Maybe he's utterly slow, maybe he's just being carefull... He's pretty serious about not wanting blown up engines coming back to his doorstep

Another reason I thought was the size of the injectors that changed, so in his eyes he would have to restart the whole testing procedure as it is virtually a different engine.

I'm seeing him this afternoon, and will ask for more details. But I don't think he is saying you can't put a Unichip on a MY98, I think he's saying it is a big job to do a proper tuning.

Rich, I'm somewhat puzzled by the fact that PS don't seem to recommend the Unichip boost controller ... it's a very simple one, programmable via the Unichip itself for 8 RPM sites. We have found that 1.25 bar (VF23) in the mid RPM range is not a problem on my car, but we let the boost taper off to about 1.0 bar beyond 6000 rpm (as that is where it gets pretty critical). That seems to be enough to near the limits of the standard injectors (440 cc on MY99 ?) if you want to keep it safe (read: bloody rich). This setup relies on 98 RON BTW...

You can also play with the lower RPM sites to reduce the slightly bigger lag the VF23 produces compared to the TD04L.

Holding 1.15 or 1.2 bar to the redline sounds a bit risky to my (amateur) ears.

Theo

EvilBevel

Adam,

The Unichip is a (rather sophisticated) piggy bag chip still... You still rely on the standard ECU doing the right things, and then adjust timing/fuelling is a plus or minus way (litteraly). If the standard ECU is way off for a reason, or reads inconsistent values, you can't "fix" that with the Unichip.

You will get something like "crap value + 3"

A Unichip is a trade-off: you don't have to play with stuff like idling (oops, airco kicks in, damn ), the standard ECU takes care of all that, so you can concentrate on timing/fuelling/boost/water injection/launch control etc... There is no doubt in my mind that a Link/Motec/GEMS etc is a better option in some ways, but only - joke I already made - if you have an inflatable Bob Rawle in your neighbourhood...

And I don't think there is any discussion about the MAF sensor being very important (and also the Achilles heel) for the standard ECU.


[This message has been edited by EvilBevel (edited 20 June 2001).]

Adam M

Theo, thanks for clearing that up, very clear reading.

IWatkins

Hi Theo (long time, no hear),

Reason PS don't like the Unichip boost controller is that they have had quite a high failure rate on the Scoobies. It failsafes, but still fails. Not good.

Dastek are apparantly looking into the problem and hope to resolve it (last I heard anyway).

Cheers

Ian

NITO

If it's a UK/euro car then you don't even need to change the ecu. Fit the HKS EVC IV which will happily deal with larger turbo and fmic's in conjunction with the stock ecu! The uk engine is only safe upto an absolute max of 1.2bar anyway..before you run into potential piston problems so it would be well worth sticking to around 1.18bar to be on the safe side. De-catted cars with induction kit and an evc are consistently making 280+ bhp at PE with around 250lbs/ft and this is with the stock ecu which can self compensate for fuelling and ignition timing at this level of boost! If you want to run higher boost then yes you'll want a remap but make sure your engine internals are upto it first.

As for the STi, yes it sometimes has stronger internals but these aren't much good if the map is completely wrong for uk fuel. I wouldn't even consider an evc for an sti, definately worth the expense of going for the link since the std ecu is all wrong for the uk running too much advance and not able to retard the map enough to prevent det on our fuel.

Nito

ric

Hyperex:
My car is a UK-MY98 with exhaust system and removed resonator (K&N panel filter) with Samco hoses from turbo to intercooler.


Ian, Adam:
Tha MAF sensor of the MY98 isn't the same as on MY99/00 cars. Ok, the whole engine isn't the same (Phase 1 to Phase 2).

Rich:
How are your torque and power figures on PS rollers?

Theo:
Thanks for clearing up things, I didn't want to tell Marks name and the circumstances of this post. The problem for me is that I don't find anybody here in Switzerland that can do a proper remap on my car! So I was very happy to hear that Mark developped a kit for the Scooby and wrote him an email. I have to say that he is a very nice guy and he explained to me exactly why he cannot fit the Unichip on my car (MY98). One of the points he wrote was that the MAF sensor of the MY98 isn't able to read the higher boost with the VF23. So I just wanted to know if anybody on this board has a solution for this problem.

Of course the Phase 1 engine differs a lot from the Phase 2 engine. And that was also one of the points he told me.

At the moment I am thinking about buying a Link and map it myself, but don't know if it's wise to play with the ECU settings as a blown engine could result...

Theo wrote:
"I'm seeing him this afternoon, and will ask for more details. But I don't think he is saying you can't put a Unichip on a MY98, I think he's saying it is a big job to do a proper tuning."
Yep, that is exactly what he's saying! And he made me the offer to map my car with the OEM TD04 to 1.3bar with the Unichip. I am seriously considering that.

Theo I think the MY97/98/99/00 all run with 380cc injectors?!

thank you all for these answers!
ric

PS ..still now knowing what to do....maybe we should just clone Bob Rawle and send him to all Scooby friendly coutries!!!

Adam M

Ric,

I know that the MY98 is not the sae as it is a phase 1.

What I was saying is that the MAF on the 22B which copes with the VF23 as standard is the same as your MY98 (I think) as it is also a phase 1.

Similar aged japanese wrxs I believe also have the same MAF sensor and they run VF22s which flow even more air.

EvilBevel

Watty !

Funny, I just heard the exact reason (from Mark) why the Unichip boost controllers failed (I had three of them, the fourth seems to hold out). Apparently Dastek just found out, and have sent a fax to their tuners. Seems to be an Impreza specific problem, boost solenoid giving a very high voltage back to the controller in some circumstances, completely frying it

Should be fixed in the next batch (diode or something), and there is also a fix for the ones that are out there already.

BTW Ian: maybe we can do a little meet in a few weeks ? I'm visiting the UK (2nd to 9th of July), and would like to arrange a wheel alignment (after my the little Ring shunt) & powerrun at PS. Preferably the 3rd of July, coz' I will then still have "real" fuel in my car
I will mail them for a rendez-vous.

Ric, Mark confirmed that the MAF is indeed one of the biggest problems ... they can not measure the same amount of air, giving a max voltage beyond a certain point, and the ECU reacts rather vigoureously on that max voltage. You can of course clamp that signal, and try to compensate in the Unichip for the "under-reading" MAF. According to Mark again, this is not a problem at lower revs, but becomes a problem at 6000 rpm. This is where you would really "gain" power BTW: Mark does know the standard gearbox is made out chocolat , and does not want to see too much torque (read: high boost) in the midrange. So with a VF23 against a TD04L, you gain most in the 5000 to 6500 rpm range where you can hold boost a little longer without stressing the turbo or heating up the air too much. It is in that area that the MY98 MAF would not cope with the airflow.

Maybe this is bollox, dunno, but I hope I explained as accurately as possible what he is trying to say.

Adam, I think you can not compare a 22B to a UK MY98 ... different engine, ECU, and probably sensors as well. (coming to think of it : the 22B, being from MY98, is probably crap ... you know what, I'll exchange my modern MY99 for that old piece of junk, whaddayathink ? LOL )

Last thing I want to do is get in between a "tuner war" , but I tend to trust him for having a good reason not to just accept your money and play around with your car.

Oh, and BTW ... the MAF sensor on a MY99 is *exactly* the same as the one on a Seat Ibiza TDI (apart from a different connector) It only costs triple if you want to get a new one from your local friendly dealer, wonder why ?

Theo

R19KET

Nito,

A) the stock ecu runs OPEN LOOP on boost. There is NO compensation to the fuelling. 380cc injectors will be maxing out at 1.2bar, add a bigger turbo, and FMIC, and they will certainly be exceeding 100% duty cycle. Even if your Co' is ok, your injectors are way overworked.

B)1.2bar max for UK pistons, based on what ? Let's assume you're right, and 1.2bar is the MAX, 1.2bar = 17.4psi, 1.18bar = 17.11psi, are you saying that .3psi is a safe margin, when we get bigger day to day barometric changes !!!!!!!!

Mark.

Hyperex

Hi Ric,

I try not to comment too much at this stage in the BBS as i am newbie in town

Frankly, ask yourself what you want to acheive in long term. Just exhaust and filter? maybe changing your turbo and fmic too? If yes, you really need to think hard whether you want to do everything in one go (since you don't live in uk) by taking your car to uk for a proper tuning. I know its a long way but this is the only way to make sure everthing is done properly. Say you changed it to a unichip and maf is suitable and you drive happlyly for now, but if your ultimate target is to have much higher power so you will have to consider on changing the turbo and etc. Then you will have to go through all these again.
If you have problem in your maf, for sure i will suggest you for using something like Motec, so can bypass maf sensor. Know it is expensive but if you pay peanuts you got monkey (hopefully nobody will against me on this).

I have done a lot of mod for my MY97 STI (more than you can imagine, you name it), been through a lot of pain too. So i know what i am talking about, in long term will save you a lot of trouble and money.

Hyper

Deep Singh

The Link is a far more sophisticated piece of kit than the Unichip.People should really noy try and compare the two or even mention the two in the same breath.This goes not only for the kit but also for the two most established tuners for these set ups.
I have recently changed fronm the Unichip to the Link and there is no comparison,this in part is due to the expertise of Mr Rawle which I feel is unparalalled.

EvilBevel

&gt;&gt;The Link is a far more sophisticated piece of kit than the Unichip.People should really noy try and compare the two or even mention the two in the same breath.

What an incredible load of cobblers...

I thought we were having an almost constructive conversation, and then this type of sh*t comes along ?

Puhlease m8.

Theo [very Deep indeed]

Darren Thompson

What turbo does an MY98 UK Impreza use guys while we are on this subject ???

Darren.