SiHethers

SuperFlyGuy

Most experience with Dawes on scoobynet seems to be with MY99/00 engines which seem to be "safe" up to fuel cut.

My concern with your setup would be of running lean in the lower rpm range. The Dawes will improve spool up of the turbo by approx 500rpm. Cone filters, as far as I'm aware, have been known to cause the MAF sensor to misread in the low rev range as the turbo spools, so if you add a Dawes it could potentially exacerbate this causing lean running. As mentioned above an AFR meter would allow you to monitor this.

As for benefits, the Dawes will bring boost in earlier and hold onto it longer, especially with a TD05 turbo, thereby giving you a better spread of torque than standard with the same boost pressure

Cheers

Simon

Edited to add- you can crudely raise/remove fuel cut by altering the MAP sensor signal using a restrictor/bleed in the pipe from the manifold to the MAP sensor, but this is likely to cause probs as the ecu is not mapped to run boost above fuel cut engine meltdown imminent!

[Edited by SiHethers - 4/1/2003 3:50:40 PM]

dave_the_B

MY 97 102k on the clock

My boost control gubbin's has gone ****-up, all I'm seeing is 7psi.

I have cleaned the boost solenoid then swap it for another one and replaced all the pipes leading to and from it, but it still won't work.
I figure something expensive/complicated has broken so I'm replacing it with a Dawes device

I will only be running standard boost with SUL

How will the ECU react to it?
Should there be anything to worry about?

Many thanks

Dave







[Edited by dave_the_B - 3/31/2003 4:07:28 PM]

Turbo_Steve

Doubt it, mate. I've been doing this for a month now, and even running ever so slightly higher boost with it, and no ill effects.

If anything was going to go wrong, it would have been with the ECU boost control which was letting me hit 1.2Bar on cold days, before slamming into the fuel cut.

The ECU fuel cut is there to protect the car from going bang. As long as it is in place, I am confident that you won't blow your engine with the Dawes.

Unless someone disagrees with me. (Mr. Banks is known for his caution...)

shiper

I fitted a dawes to mine MY95 wagon uk and lifted to 16psi with a fuel cut lifter set at 17psi but had a problem once. The computer cut in when i seamed to over boost upto 17psi on a cold day and went into safe mode and boost stayed at 10psi. A reset sorted out so now i make sure boost doesn't go above 16psi and i;ve had no problems since.

RON

Just do it Dave, you know you want to!!!!!

SuperFlyGuy

Where do you get these "dawes devices" from and how much??

bigsinky

got mine from jamie at jw racing. would advise a boost guage, afr meter and a knocklink as well. to be ultra safe i fitted an uprated variable rate fuel pump.

cheers

big sinky

SuperFlyGuy

Thanx Bigsinkey.

Am I to understand then that all those instruments are there to simply "monitor" or is there a need to "adjust"?. I know everyone just wants a bolt on performance booster but this Dawes Device sounds like it needs a bit of setting up. My boost gauge usually peeks at around 15psi (fuel cut at around 15.5psi for 1 second) so will I see any improvements with this? (got cone filter+ s/s back box).

Scratch

iTrader: (1)

How do you know what the fuel cut is set at and how do you adjust it ?

bigsinky

@superflyguy

you are right about "monitoring equipment" but i feel it is cheaper than an engine rebuild. my dawes will be set at around 1.1 bar (16 psi approx). this combined with an H+S downpipe and also running SUL with NF black bottle(100ml per tank) allows for strong boost (i.e 1.1 bar from about 3500 right to redline). i takes a bit of fiddling to get the correct setting but once there it is leave as is. the variable rate fuel pump also helps when using a bit more boost as the standard fuel pump in early wrx are ok but really only rated for about 0.8 - 0.9 bar.

best bang for your buck IMO but be sure that you don't have the real bang. there is only so much 370cc injectors will do and i recon i am close to it ie circa 280 - 290 bhp. if they did proper remaps here in Northern Ireland i would jump at the chance. maybe might go to bob rawle in the summer so he can divest me of 1200 odd quid!!!

SuperFlyGuy

Scratch - the fuel cut is an electronic safety limit built into your ECU. I'm not sure if you can adjust it on a standard ECU which is why people change or "chip" to modified ones (with a higher boost limit).

You know what the limit is when you fiddle with the boost (providing you have a boost gauge). The ecu will cut the fuel when it's boost limit is met or exceeded. It feels like you have just hit a brick wall, that's how you know your on the limit!!!

SuperFlyGuy

Thanx Simon....

It seems the best way to modify these critical operations is to use a proffesional tuner with a lap-top, rolling road and hand over a fair bit of dosh....I suppose you will then sleep better knowing your engine will not turn into a molton mass of scrap!!

Mmmm... i will leave her alone for a while.

RRH

have a look here
it should answer all the questions you may have

simon


[Edited by RRH - 4/2/2003 10:01:45 PM]