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Old 23 July 2001, 12:10 AM
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Scott.T
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Why do posts like this make you nervous.

I was just providing fellow Subaru owners with information I obtained from 'a secret' Superchip source.

Many posts have been put on here regarding Superchips and what boost levels a standard and modified Subaru runs at.

I was just helping out those who have posted such questions.

I'm sure Superchips know what they are doing as they have been around since the start of 'the Chipping Era' (O.K so the MY99 figures are probably wrong).

I'm sure that there are alot of companies out there that have done alot less research than Superchips, although I'm not promoting their product as I feel it is very overpriced for what you get.

Yes, there are better products out there but at massive cost compared to what you can do with small amounts of cash and a bit of common sense.

I know of many reputable companies that have used Bleed valves to give sensible improvements in power without the need for fueling adjustment and such mods have been performed on countless Turbocharged cars for many years.

The key to this is 'BE SENSIBLE'......and most if not all Turbocharged car manufacturers have an overhead on the boost, which just gets turned down for 'Production'. i.e many press cars will run at higher boost, then the subsequent Production vehicle will be set at Production levels (i.e Series 1 RS Turbo was reported to be at 10psi on Press vehicles, production vehicles where only running 7psi).
Old 23 July 2001, 07:45 AM
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Scott.T
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Here's a list of the 'Boost' limits advised by Superchips when fitting one of their conversions.

Subaru Impreza <97 - Maximum modified Boost pressure 16psi - 1.1Bar
Subaru Impreza >97 - Maximum modified Boost pressure 16psi - 1.1Bar
Subaru Impreza WRX (95) - Standard Boost 16psi, Modified Boost 19psi
Subaru Impreza WRX - Maximum modified Boost 18psi - 1.35Bar
Subaru Impreza >99 - Boost Pressure as standard is Peak 17psi, holds at 16psi. Boost Pressure as modified is Peak 21psi, holds at 20psi.
Subaru Impreza >01 - Standard Boost 14psi, Maximum modified Boost 19psi - 1.2Bar

All of the above mods use just a bleed valve and a gizmo in line with the MAP sensor to fool the overboost protection.

You could probably do the same with a £20 Bleed valve, although I'm not sure when the standard overboost protection would trigger.

I know alot has been said on here in the past about Superchips/Subaru's not mixing.
Well, personally I feel that if the limits detailed above are followed and a Boost gauge in fitted in the car then no problems will arise.

If however the owner has a tendancy to fiddle with the bleed valve and doesn't keep an eye on the boost, then trouble will be just around the corner.....BANG !!!!!

[This message has been edited by Scott.T (edited 23 July 2001).]
Old 23 July 2001, 08:35 AM
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chiark
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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Scott.T:
<B>Subaru Impreza &gt;99 - Boost Pressure as standard is Peak 17psi, holds at 16psi. Boost Pressure as modified is Peak 21psi, holds at 20psi.
[/quote]

Cheers for that Scott, looks very interesting and pretty "official" being from Superchips themselves

Hmm, my MY00 never hits those boost targets and I suspect neither does anyone else's. 15.5/14.5 in cold weather, or 15/14 are the norm. I believe overboost protection cuts in around 18psi.

This worries me that they're starting from an "increased" playing field.

Raising to hold at 20 sounds quite a massive increase to me with no further mods, such as fuelling. The 18 (or so) PSI overboost ECU limit is presumably there for a reason?

Nick.
Old 23 July 2001, 08:46 AM
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Scott.T
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Yeh, the MY99 figures are a bit strange, although they came from the same source as all the others.

I'm not that clued up on the differences on an MY99&gt; so cannot comment any further.

I would suggest that the figure of 16psi max as used on the other UK spec models is best ahered too.

Cheers.....
Old 23 July 2001, 09:22 AM
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R19KET
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If you want to up the boost a bit (couple of psi) then the Superchip is a very expensive way to do it. You'd be better off just using a bleed valve, and keeping below the ecu "fuel cut" settings. This would also keep you "reasonably" safe with a UK car.

There's NO way I'd play with an import. Most of them are already running on the edge of safety, with the ignition map, let alone increasing the boost.

Mark
Old 23 July 2001, 09:33 AM
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Scott.T
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R19KET,

I totally agree with the Bleed Valve comment. Hence, the reason for this post.

Why pay £350 when £20 and a bit of common sense would suffice.
Old 23 July 2001, 10:01 AM
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Trout...
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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by chiark:
<B> Cheers for that Scott, looks very interesting and pretty "official" being from Superchips themselves

[/quote]

It may be official, but is also incorrect. The figures for the MY99 for example are NOT a UK car, but an STI; the figures state 19psi is 1.2bar - it is in fact 1.3bar.

I am impressed by Mark's conservative response. Take an MY99 Sti, increase the boost to 21PSI peak, 20Psi and watch you car lose its pistons in extremely short order.

The two key issues are the lack of fuel from the standard ECU and the rapid increase in inlet charge temp as the poor old VF28 suffers from thermal stress.

Sorry mate, but a dangerous post

Trout
Old 23 July 2001, 10:05 AM
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I think we've already established that the MY99 figures 'as supplied by Superships' are a bit inaccurate.
Old 23 July 2001, 10:22 AM
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chiark
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...from which I conclude that I would not put anything from Superchips anywhere near my car.

Sorry, I should have made that clearer in my post.

I daresay 20PSI would feel good for as long is it lasted. So, would the TD04 or the engine give up first on my MY00?
Old 23 July 2001, 10:33 AM
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SecretAgentMan
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Wink

18 psi and the Link works great...bit more expensive than 20 squid for a bleed valve though.

Go on Nick..U know U want it.

/JMan
Old 23 July 2001, 11:18 AM
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chiark
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j/

I'm being sensible. Brakes first, sir!

nick.
Old 23 July 2001, 11:47 AM
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And...isn't that sorted mate?

Old 23 July 2001, 11:55 AM
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Trout...
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Chiark,

wasn't having a go at you - just, as you say, clarifying.

Posts like this do make me nervous - not for me, but for those with selective eyes

Trout
Old 23 July 2001, 03:56 PM
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R19KET
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Most people know my feelings about the use of bleed valves/Superchip/FCD for increasing boost. It's crude, unreliable, and asking for trouble, but there are always going to be people who go ahead anyway, regardles that they are ignoring the very advice they asked for.

My previous comments were for the poeple who think a £20 bleed valve will do the job of a re-map.

The reason that there are so few posts relating to "specific" cars having blown up, is that most of them are kept quiet for "warranty" reasons.

Mark.
Old 23 July 2001, 04:08 PM
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Where in my post does it state that a £20 bleed valve will do the same as a re-map.

If people are putting Bleed valves and mods onto cars still under the 3-year warranty, then they are fools to themselves (unless it's a PPP)

I have nothing against re-maps. Several of my previous cars have been succesfully re-mapped by the likes of Power Engineering and Brodie Britain Racing. All for about £150. It's gonna take alot of persuading to get me to splash out £650 for 30-40HP.

I'd rather spend £20 and get 20BHP more.

Those that use Bleed Valves do and those that have spent wads elsewhere don't.

Those that use Bleed Valves to achieve MASSIVE boost are asking for trouble.

Those that use Bleed valves to increase by 2-4psi are doing nothing wrong, just don't increase by anymore, and make sure you use a decent boost gauge.
Old 23 July 2001, 06:18 PM
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Scott,

I was generalising, not specifically singling you out. However, now you're saying it's ok to run 18psi, using a bleed valve, and you won't/shouldn't be able to do this without fooling the ecu.

18psi (1.25bar) on a UK car, is at the maximum level an experienced, competent tuner would run, after a TOTAL RE-MAP, and 2psi higher than a standard STi.

This was my point. Ask for advice, don't like the advice given, decide on some "notional safe limit", and risk the engine.......

I hope you're luckier than some others I can think of.

Mark.



Old 23 July 2001, 07:24 PM
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steve McCulloch
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Chiark

uprated brakes?....... a granny would be overtaking you, you go so slow!

I know of one UK car that runs 21psi - very dangerous as its a simple 'bleed valve' type design - theres no det though - but somethings bound to go!

My sti5 in std trim peaked at 15psi and held less than this - and a UK car is much lower than this

Ignition advance seems to be the way to go on a decent ECU with everything else sorted - octane boosters, water injection.

Old 23 July 2001, 07:46 PM
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Bob Rawle
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Scott, nice one, good debate.

I suggest that the correct boost figures for each MY and car type (UK and Japanese spec) are posted before the debate goes too far as the figures Scott has been given are not correct in their entirety, for example a MY95 car only ran 13 psi boost (up to MY96 had TD05 turbos which move virtually as much air as a VF22), UK cars do not run the same boost as STi's and will not stand the same increase. Also Japanese spec WRX cars are not like their STi brothers but more like the UK version so more care is needed.

Fooling around with the oe ecu inputs is only ok for as long as everything stays safe (fueling etc). It has been done successfully though (with some risks)

Early cars (up to MY96) were fueled less generously than the later ones.

Superchips developed this as a "quick fix" as the number of cars in the UK did not justify their R & D. Since there are currently four different ecu designs across the model years they would have to be perpetually working on it. (almost)

Trout, I better watch out for my pistons then cos my boost ends up there quite often (ok, ok, don't say it)

Just to show variance my STi 5 in standard trim peaked at 18 psi and held 17psi but detted even running booster.

Old 23 July 2001, 10:39 PM
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Talking

Bob,

spooky this is your 555 post!

Anyway, I couldn't resist saying it - your boost may end up there, but as we both know your fueling will spot on and your advance perfectly mapped and controlled - unlike a 'fooled' standard ECU suddenly seeing an extra 40% of air with no extra fuel.

Scott - my nervousness lies in the selective reading. If, as Mark says, someone has decided to go down this path they will read the first bit and think, mmmm that sounds alright, I'll have some of that. They will choose to combine the officialness of the source and your comments saying that there should be 'no problem' if these are followed.

Just remember there is someone very famous on this board whose car suffered terminal det 24 hours after fitting a superchip and bleed valve - we all live and learn.

I am not saying don't post - I guess just make all the caveat emptors clearer.

Cheers,

Trout
Old 24 July 2001, 12:11 AM
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So if I turn up at BRD and ask for a 'Link' they will replace my MY94 ECU with the 'Link ECU' and re-map it, right ?

So what's that gonna cost ?

And what sort of Boost increase can I expect ?

And does it Require a 'Bleed Valve' ???????

[This message has been edited by Scott.T (edited 24 July 2001).]
Old 24 July 2001, 12:20 AM
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Scott,

"Those that use Bleed valves to increase by 2-4psi are doing nothing wrong, just don't increase by anymore, and make sure you use a decent boost gauge."

Most UK cars will hold circa 13/14psi, add the "4psi" from the above statement, and I think that makes about 18psi !!!!!

Mark.


Old 24 July 2001, 08:19 AM
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Where did I say it's O.K to run 18psi using a Bleed Valve.....why do people keep mis-quoting me.

We've all agreed that some of the 'Superchips' data is incorrect sepecifically being the MY99 figures.

There's no way I would run 18psi on my Scoob, and yes I am running a Bleed Valve, but I'm even doubting whether I should be running at 16psi peak (with Octane Boost), which is only 3psi higher than the gauge was reading before the Bleed Valve was fitted.

If someone in the 'knowledge' could clear up the debate on the correct Standard and Modified Boost levels to put these Superchip values into perspective, then we could close this matter once and for all.
Old 24 July 2001, 08:47 AM
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chiark
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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Trout:
<B>Just remember there is someone very famous on this board whose car suffered terminal det 24 hours after fitting a superchip and bleed valve - we all live and learn.
[/quote]

Who's that then???
Old 24 July 2001, 09:25 AM
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Erik
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Question

Ok but what is maximal safe boost limit on UK MY98 for ie. 95 oct fuel? I can simply buy +99 oct Vpower Racing but is`t f**king expensive. And finally witch one bleed valve to use? My favourite is from GATED BCV TYPE II from
Old 24 July 2001, 09:58 AM
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Adam M
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Scott,

I think Bob and Mark are both people in the know when it comes to mapping. When it comes to standard cars boost leves, I think you will find that bob singly has the most experience of the highest number of different impreza models, so I would believe his standard boost values over anyone elses.
Old 24 July 2001, 10:17 AM
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Andy Tang
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<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Scott.T:
<B>Where did I say it's O.K to run 18psi using a Bleed Valve.....why do people keep mis-quoting me.[/quote]

The way I read it Scott, no one is saying that 18psi with a bleed valve is ok, not even you!

I guess what people are saying is that a newbie may scan read this post, and then think it's ok to run 18psi on their car!

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Scott.T:
<B>We've all agreed that some of the 'Superchips' data is incorrect sepecifically being the MY99 figures.

There's no way I would run 18psi on my Scoob[/quote]

I'm using a HKS EVC4 (electronic boost controller) I run 17.3 psi as my peak boost, and it holds it as well. The overboost is set is 18.3psi (which it hit twice in sub zero temperatures). I'm not saying this is the way to go, but I know other people use this method (rightly or wrongly).

Before people start going on about fuelling, ignition timing, etc, I have to mention that I'm getting a Link fitted in a months time!

I know of one Superchip car that left the workshop running about 25psi peak! It was a MY97 UK car!!

As with all these things, they are as good as the person who installs it.

Andy

Old 24 July 2001, 10:22 AM
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Adam, I don't think Scott is questioning the values that Mark or Bob put forward.

We can say a thousand times that bleedvalves are bad, some people will play with them anyway (because it is so cheap). Some move on to more serious tuning, some blow up there engine, some will be perfectly happy for a long time.

As long as we are quoting numbers: a UK MY99 that runs about 1.2 bar peak on 98 RON fuel will not det or run lean (read keep at about 9 % CO and above), and will last in most cases... I've now seen enough examples of that, so it's not just opinion.

97 RON seems to alter the picture. IF (mark the if, I would never fit a bleedvalve) I would use one, I would stay (like other posters said) under the normal fuel cut, so try to adjust for 1.1 bar.
Old 24 July 2001, 10:23 AM
  #28  
Scott.T
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Andy,

How much is an HKS electronic Boost controller, and what else is required to adjust the fueling and ignition as required.

What other options are there, without spending shed loads (by shed loads I mean £700 for a Phase 1 or £1700 PPP)

As EvilBevel say's. We've all got to start somewhere and may well move on to greater things.

I'm currently running a Bleed Valve on my MY94, set to 16psi Peak. And as mentioned above it was peaking at 13psi standard. So is only a 3psi increase.

[This message has been edited by Scott.T (edited 24 July 2001).]
Old 24 July 2001, 10:35 AM
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Andy Tang
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Scott,

To be honest, once you've bought the HKS EVC4 (between £400-500) and then buy modules to to adjust fuelling and ignition timing, and had them professionally fitted, you could have bought.....

a Link and get it fitted and mapped by BRD!!

I bought my HKS EVC second hand and it's been fun, but I now want more safety and expandability!

Food for thought
Andy
Old 24 July 2001, 11:06 AM
  #30  
Scott.T
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Is a link fitted in addition to the HKS Boost controller or is it a stand-alone item.

Excuse my ignorance - but I'm just used to the likes of Power Engineering just whacking in a chip and re-setting on the rollers for my previous Ford RS's.
Not used to all this modern electrickery


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