chiark

Morning all.

I'm after a bit of advice. I'm running K&N induction, scoobysport downpipe, standard centre and scoobysport back box on my MY00 turbo. I like it, a lot.

What would be the easiest, safest and cheapest way for me to up the boost a little? I see talk of turning the actuator, dawes, FCD, ...

Any recommendations greatly appreciated.

David_Wallis

FCD, Dawes, & Actuator ==

David

P20SPD

iTrader: (1)

Got to agree, when you look at prices, thats the cheapest way for bigger grins

The other cheaper way is t never go in a car that has more power than yours, cause then you want better.

P20SPD

iTrader: (1)

Why would you need the fuel cut though, surely you would not be uping boost that much, would you

David_Wallis

Why not??

I would go to about 17psi... (well actually I would go to 28psi but not on a td04)

David

P20SPD

iTrader: (1)

Did not think fuel cut came in until about 1.2bar, which is approx 16.5 to 17psi.

STi wanna Subaru

iTrader: (1)

I think it's 17.4 Psi on the MY99/00 cars. I run a dawes with full de-cat. In 5th it holds at 17 psi and then drops off.

Nick,

If you want a drive in my car to see what it feel like let me know.

Guy

chiark

So Dawes is still the way forward then... Any other options?

David_Wallis

pull a hose off

john banks

Dawes is great. The 1.5mm bleed hole all but sorts the part throttle issues. If you have the MY00 ECU also worth sourcing a MY99 ECU.

Fuel cut on MY99/00 is 17.6 PSI held for approximately 4 seconds. Aim for 16.5-17 PSI and you'll be fine or alternatively find fuel cut and then turn it back one half turn beyond where you just don't get fuel cut.

Above fuel cut on the standard ECU and it retards quite a lot. Not much value in going over 18 PSI anyway on TD04L.

If you do want to raise fuel cut you can bleed off the MAP signal hose or use a needle valve in the line to it. Worth setting it up with a voltmeter on the MAP signal and a syringe to pressurise it.

chiark

Cheers John, I understood about half of that

So where do I get the bits from. Speak slowly, you're dealing with the hard of thinking here

IainCam

What about on the earlier ones? I've a MY94 running at around 13-14PSI (think the early FC comes in at 14.5?) on a TD05. Am I right in thinking that they can handle 17-18PSI okay too?

Any ideas as to expected power running at that boost on a TD05 (fully decatted and induction kit)?

Iain.

uxg

Sorry to sound like a complete newbie but does anyone know what a Dawes device will do with regards to reliabilty of your engine. I mean I have a Vf23 hybrid turbo which is currently running standard boost so I would love to up the boost just a tad to maybe 15-16psi. I though I would have to get a re-mappable ECU but these cost quite alot of money which would mean I would have to wait a while to save up for one.

The Dawes seems like a very cheap alternative but after reading all the horror stories of engines going bang surely a £40 device which ups the boost can't be much good for engine reliabilty. I mean correct me if I am wrong but do you not need to alter fueling and a host of other parameters to safely up the boost. If not then why do people bother paying £1000's to get ECU's and re-maps when they could buy a Dawes instead. Not being a doomsayer just genuinely interested to know what people think. Basically could I put a Dawes device in a STi Type R and up the boost a little and expect my engine not to go bang.

IainCam

Think it's not something that's as much a problem on the UK cars as it is on the imports. AFAIK the imports are designed to run on a higher RON of fuel so by running them on the lower grade in this country, you are already pushing your luck so by upping the boost with these it's probably more likely to be a problem.

I've had the Dawes on for a wee while now and haven't had a problem with it. The Fuel cut limit is still set as standard on mine so I'm still within the limits Subaru designed for. All the Dawes allows me to do (at the moment ) is get more boost and get it quicker. Obviously if I up the boost above the FCL then I'm starting to "push my luck" a bit but from what I've heard so far the earlier cars can take a bit more boost as they are lower boosting than the later ones (due to the bigger turbo).

I'm not that technical though but I'm sure John can let you know a lot more

PS I do know someone with an STi who's been running a Dawes for the same time as me with no problems I know of

jonmyers

If i answer one question, can i ask another without hijacking the thread?

You can get the Dawes from Jamie at JW Racing 01642 894 637.

Now, uxg, how do you find your vf23 hybrid?

uxg

Just as I thought, should have known better than to get my hopes up at getting some cheap extra boost Even look at an import in the wrong way and it'll go bang or so I am begining to believe after all the horror stories on here. Oh well I guess I'll have to bite the bullet and go for a replacement ECU as soon as I can get the money sorted out, for peace of mind as well as upping the boost.

As for the VF23 it is definately laggier than the VF28 unit I had on before (although this has been somewhat sorted out buy the forge VTA dump valve which I fitted recently) but once it get's going properly at around 3500rpm....wow. Pulls like a train all the way to the 8000rpm redline where the previous one would run out of puff at around 6K. Defiantely a big improvement higher up the rev range over the old unit although it still feels like it could do with a bit more boost which is why I need to get it re-mapped and at the same time I will see if anything further can be done to reduce the lag. Like I said the dump valve seems to have cured it somewhat with the turbo now staying properly on song between gear changes but try putting your foot down at anything under 3000rpm and it's wait wait wait.

john banks

Get a knocklink before you consider raising fuel cut.

UXB don't use a Dawes on your STi for the reasons outlined.

[Edited by john banks - 9/16/2002 9:23:24 PM]

Floyd

iTrader: (9)

Hmmm.

You can use a Dawes safely on a UK car and it's fairly idiot proof - up the boost too much and you'll fuel cut then you'll have to turn it down until it doesn't, see. UK cars over fuel so no real probs there, you may want to get an air fuel ratio thingy but that will just tell you what I have just said! Get a boost gauge to look like you know what you are doing.

For £35 quid you can't really go wrong - good bangs for bucks (no pun intended). Once set up (10 mins) you'll definitely know it's there and that "we go fast" "we are smart" as the 'Packleds' say.

But, on a daily commute and in heavy traffic, the power delivery can be somewhat tiresome. Now you see it, now you don't.

Then, you'll want a PPP or a Tek 2 to move to the next level.

It will happen....

F

jonmyers

Well i had a Tek3 from John B and was going to drop the dawes then but John convinced me to stay with it and i'm glad i did. I don't find town driving anymore tiresome than anyone in a scoob! Well, that's my twopeneth anyway. At least you can try with and without very easily and choose for yourself.

that vf23 is gonna fly once mapped!

IainCam

I take it then that the knocklink is different to the AFR then? I assumed (wrongly by the looks of it ) that as long as I had the AFR and boost gauge that I'd be fine.

Anyone know just how far is safe to push it on a MY94/TD05? 18PSi the max or with the knocklink and AFR just push it as far as you can without knocking and red lights?

john banks

There are lots of factors that influence things, and it would take a long time to discuss them all. Read a few books first - e.g Maximum Boost, Corky Bell. 21st Century Performance, Julian Edgar. Both from Amazon.

chiark

I have a knock link, but don't trust it as it really needs calibrating against a known det signal to be useful...

Is lambdalink (or AFR) advisable?

P20SPD

iTrader: (1)

Yeah but surely it cant pick up a great deal of knock with where it is positioned on your car. I thought the best place was underneath the intercooler on the block at the passenger side, IIRC.

LG John

Floyd I spotted your star trek pun even if nobody else did

Floyd

iTrader: (9)

SB, well done. I try to put a little subtle humour in my posts but it probably goes over the heads of most

John B, the thing that I can't reconcile myself with is fitting a crude DD with a fancy ECU. I believe that going for a link or TEK etc is the reason I'd choose to get even more power safely and still retain electronic control of boost. It just feels like you're (not you literally) dabbling with areas outside of the ECU perameters again. Plus you've still got that brass thingy flapping around!

F

Chris.Palmer

IainCam,

Standard fuel cut on a pre My97 is around 15.48 PSI

If you go higher than you are currently running then you'll need to raise the cut limit.

If you do raise the cut level 15.5 PSI is a safe limit - as some the pipes on the earlier cars are known to blow.

Chris

john banks

There are users of Link, MoTeC, Ecutek and other ECUs who are using/dabbling with the Dawes because in a lot of cases it works better with better spool up, especially in lower gears, and less boost spiking, especially on track or in different conditions. A lot of ECUs do not have really good closed loop electronic boost control - even some EBCs do not. The only issue that I can see is that the ECU cannot pull the boost if it sees uncontrollable detonation. If it was that bad you should hear it, but if you have the ICE on the Knocklink would blink at you frantically. It goes ballistic with even traces of detonation if you have it in the right place.

It felt a bit "improper" being an ECU mapper and admitting to myself and others that the Dawes was actually better at it than my precious ECU but after that hurdle, I and others really appreciate the quality of the boost control it provides. You still benefit hugely from the ECU, especially if you want to run quite high boost or have a lot of mods. With my car as it is with fuel pump, FMIC, turbo, ported manifold and APS induction kit it would be almost undriveable without the remap, and certainly after the 550cc injectors.

IainCam

Hmmm, why does mine tend to hit FC around 14.5 then?

Saying that I haven't tampered with it since getting the new boost gauge so might be worth playing a bit more with it now

I do plan on raising the FC later on in the yearbut will have a look at it tonight ;D