john banks

Got you there!

I swapped back to normal decat PPP this evening and boy was it slow. It was holding 16 PSI and boost was in single figures by 6500rpm. Unbelievable that I ever thought this was quick, but they all say that when they increase power. If T-uk thought the top end was flat on a Dawes car, try a PPP and weep - the midrange is good but the top end seriously lacking - like a fugging diesel! Seriously it is lame in comparison. No other description. I wonder what a VF23 drives like same again probably and the rest.

Reason for this latest bit of driveway tuning was because I was concerned about possible lean conditions during spool up as I wasn't seeing 5% CO until 10PSI at 2200rpm with the Dawes. However ignition advance was OK and Sam pointed out that you can be quite lean below 3000rpm.

So I went back to the PPP and checked that. It is exactly the same, but based on boost not RPM. So by the time the PPP reaches 10 PSI at say 2600rpm it is only showing just 5% CO, and the 7+ % CO only shows after it has hit 15PSI as with the Dawes.

I know all these Dawes posts are boring, but I hope this is useful info.

Of note - the Dawes with a bleed drives just as smoothly as PPP, and the part throttle boost is comparable. However, without a bleed you can have the Dawes at full boost, and just richen up the mixture and exhaust note by moving the right foot which is a worrying characteristic. Strongly recommend a bleed.

[Edited by john banks - 03/01/2002 18:18:17]

RB5SCOTT

So to finish it off then John, a couple of Dawes questions

Can i use it?

where from?

how much?

Setting up? lol

thanks,Scott
i think you know my mods,

btw, my boost is running at just over 1.2bar (around 18psi)

[Edited by RB5SCOTT - 03/01/2002 18:39:59]

john banks

I think you could use it but would check you air fuel ratio with a suitable device, and check your ignition advance on a RR. You may also want a knocklink if you don't already.

Two cautions with your car - apparently a MY01 has smaller injectors so I would check your injector duty cycle on the select monitor. Also you are more likely to run lean as you have had your headers done I believe.

www.dawesdevices.com £26 in group buy. There could well be enough to organise another?

Install by putting the Dawes in instead of the restrictor hose, and cap off and disconnect the solenoid. Remove the T/Y piece. Check on boost gauge and go up to 18PSI as you are at now.

You will get a significant gain at the top end and the bottom end from this and your spool up will be quicker. Your midrange will change not at all. Your are flattening and widening your boost curve as far as your turbo can flow it basically. If you go lean though there is probably not much you could do to adjust it unless you buy an ECU or fuel computer though, but my MY00 is OK running 14.5PSI at 6500rpm, and 18 PSI by 2400rpm held until about 5300.

[Edited by john banks - 03/01/2002 18:45:46]

RB5SCOTT

Thanks for the speedy reply John

I have now got a HKS fuel controller, so lean isn't a problem and last time i checked the ignition was advancing at about 6 degrees max. As for the injecters! i have'nt got a clue.

Gives me something to look at
thanks again
Scott

[Edited by RB5SCOTT - 03/01/2002 18:48:51]

[Edited by RB5SCOTT - 03/01/2002 18:54:09]

john banks

If you have a fuel computer it seems almost rude not to do it.

T-uk

john,

take it the Dawes is back on then .
saying the car was flat higher up was my paranoid way of saying,"this ***** holding some ******* boost higher up,sure it's okay" ,anyway stop playing with the thing and drive it,see you at Knockhill ya lunatic



[Edited by T-uk - 03/01/2002 18:59:53]

john banks

"Tonight I will mostly be making boost controllers out of regular household items such as you would find under the average domestic kitchen sink."

Later on I am going to see just how rich it is from 3000-7000rpm. I will of course post. Who knows, from the looks of my zorst it could be >10% CO. Who needs water injection now??

[Edited by john banks - 03/01/2002 19:03:30]

GavinP

Had me going for a minute there John....

As you say "there is no going back..."

If you think a Dawes makes a big difference to a MY99/00 car, you really want to try a before and after on a MY94-96 car ! Nothing and I mean NOTHING below 3200rpm then wallop! Makes a huge difference to the driveability.

Keep up the dialogue - I'm sure a lot of people appreciate your efforts (myself included)

Thanks

Gavin

john banks

I will dreaming tonight of turbos the size of Ireland spooling up.

Scott.T

iTrader: (2)

How are your plugs John, as mentioned before mine were getting pretty black and wet with the Dawes fitted. Probably due to the fact that I can't boot it around all of the time. Especially with the nipper in the car.

Have reverted back to just a bleed valve and so far the plugs seem fine. Perhaps with the Dawes fitted the ECU was richening things up too much on light throttle loads.

john banks

With the Dawes it seems to fuel the same boost for boost as the PPP.

At 3000rpm 18 PSI it is showing 7% CO. At 5000rpm 18 PSI it is 9% CO and stays up there (or higher up to the redline). This is a little higher than I want, but some do map to 9% CO for safety and cylinder cooling. I would prefer it a little leaner I think, but it is quick enough.

Don't know what the plugs look like. If your car is not running well could that be your explanation?

I can't see that I am running any richer than PPP with DP did.

RB5SCOTT

Dam you John you have really got me thinking about this Dawes now and once i've got something in my head i've just gotta have it

Really i will need a fuel ratio sensor aswell to set it up( i don't fancy giving PE £130 to use their rollers and co2)

Have you got a Dawes one, or did you make your own?

Scott

john banks

Just see the make one for yourself £10 thread in drivetrain.

RB5SCOTT

A bit technical for me

john banks

If you can program a fuel computer you can do this. Or just buy a lambda link?

Sounds like you should have a Knock Link too?

RB5SCOTT

OK then, here comes starship enterprise

mutant_matt

So John,

You are saying that the Dawes with Bleed Valve is the way to go? How does this compare to a drilled out Dawes? I know if you drill out the Dawes you don't have any adjustability but if 1, 1.5 or 2mm drilled out gets it how you want it, do you really need the bleed?

Ta,

Matt

HarryBoy

Hi Matt,

Iam not using a bleed with mine, I have left it standard. I am not finding the throttle 'sharp' as John is (was). John's car comes on full boost much quicker/stronger than mine and (I may well be wrong) I think it is this that is causing the car to be less than desirable when driving, John mentioned it's behaviour through corners IE: the power comes on stong mid way through causing the drivability to suffer.

My car is still drivable aroung the 2500 RPM range, even though it is stonger here than stock. It's only when it gets to around 3000 RPM that the real action starts.

Harry

john banks

Drill or hole or use a valve it is the same effect, just tidier but less adjustable if you use a drilled hole.

SPEN555

John,

When you say drill a hole or make existing hole bigger do you mean the tiny pin sized hole which is on the elbow of the Dawes?

Damian.

Lars

I need you help
I have the Dawes MBC installed and it's great, but now I need to go back to standard before a 50.000 km service check.
Where do the original restrictor hose go ( The longest of the two hoses), between the T and the westgate or before the T ?

I feel sheepish by asking, I should have made a remark on it before installation.

Thanks in advance

mutant_matt

John,

What I meant was, do you know what size hole you need to have on the Dawes to be the same as how your car now runs with the Bleed valve from a part throttle drivablility standpoint?

Ta,

Matt

Scott.T

iTrader: (2)

John,

Car is running fine apart from the hesitation mentioned on the other post. This hesitation has been there since April. The plugs have been in an out several times since then, and this was the first time they were blacker than normal.

PE and Barratts seems to think it was fueling OK when trying to cure the hesitation.

I'll take a plug out this weekend and see if it differs to when the Dawes was fitted.

john banks

http://www.whitetyphoon.com/impreza/spark_plugs/

Found this link on how to remove and replace spark plugs. Can't be bothered to do it right now to be honest. I know my car is essentially fuelling very similar to a PPP car. Perhaps yours dumps fuel in if it sees high boost?

The Dawes is only changing the shape of the boost curve to what a lot would run with an EBC or aftermarket chip. If your ECU messes up the fuelling then I suppose it is not very useful on your car.

[Edited by john banks - 1/4/2002 5:17:09 PM]

Scott.T

iTrader: (2)

It's still seeing high boost as it's running a Bleed Valve, and is set to 14psi, which is the same as I had with the Dawes.

I'll run it for another week as is, then try the Dawes for a week or so. But shall do an ECU reset when the Dawes is re-fitted.

john banks

But presumably it is not boosting as high at high revs which is where I suspect it would be dumping fuel from watching where my car is richest?

carlos_hiraoka

John I don't know if you have read the following before, but if not take a look .....

http://www.autospeed.com/A_0670/P_1/article.html (part 1)

http://www.autospeed.com/A_0685/page1.html (part 2)

Carlos H.

john banks

Yeah seen them thanks. Our setup is quite similar.

carlos_hiraoka

Have you tried TURBOXS HPBC ..... ? is it like the system you are using ?

Carlos H.

john banks

No, but it seems to be just the same. Now I am working on http://www.scoobynet.co.uk/bbs/threa...threadid=63226