Manual boost controller
 

I was wanting a wee bit extra power out of my blob eye wrx (ppp), and this seems a very cheap way to get it, ive read threads on this about the manual boost controler causing damage to the engine, and that u have to supply more fuel for the extra air, so i wondering does the ecu have a bit of play in it to feed more fuel for the extra air or when i go above standard boost will it start to run lean without any correction from the ecu. If the ecu can manage the extra air flow upto a point what would a safe amount of boost be? been looking at the dawes device boost controller.

thanx for any help.

Yes a MBC can be used to up the boost slightly and the ecu will increase the fuel to compansate for the extra air. yes the dawes device is the one to get but there are other mbc`s on the market which work in the exactly the same way such as the r-tec mbc. If you haven`t got one you will need to fit a boost gauge first before the mbc in order to set the boost. a knocklink is a good idea too.

So what sort of extra boost can i run with the ecu being able to safley compensate for the extra air. does a knock link sensor just measure the vibration in the engine block?, do you know and good places to get one from.

cheers again

get a boost gauge fitted first and see what boost you are running standard and then we`ll go from there. knocklinks are few and far between but sometimes crop up on ebay do a search for detalarm

ok cheers i will do that.

You can have my Dawes for a tenner in a week or so if you like. Just waiting for for some new bits.

why are u getting rid of the dawes device? did u find it made a noticble difference, how did u know what was a safe boost to run with it,
do u know if it will fit to a 05 plate ok, will the pipework you cut for urs fit to my car or will i need to get some new pipework.

It fits all models. I had it on my classic to bypass the Boost Solenoid as it was fubarred. I am replacing it with an electronic boost controller. I had the boost set to 1.1bar and it did make a very noticable difference, I should add that mine was also mapped for 1.1bar. Plenty of people use them without a remap or chip to good effect. The Dawes is only as dangerous as the user! As long as you do not pust it there should be no issues. As said above you really should fit a boost gauge first or at the same time.

well if u still want rid of the dawes i will take it of you when ur ready.

No worries, its yours. Will PM you in a week or so.

ok no probs.
cheers.

i have a boost gauge, chipped ECU and a MBC. mines boosting at 16psi, which is about 1.3 bar i think. it runs brill, and i have had to tape up the MBC now so i dont go mental with it!

16 psi is 1.1bar.

tell a lie its about 1.1 bar. !!

i know now lol. just checked. whats safe psi to take a standard turbo on a 99 classic to then?

What chip you got?

superchips as far as i know. think car was done at well lane in west yorkshire

Superchips huh. To be on the safe side I'd get the Fuel/Air checked with that chip. Not the best on an Impreza (based on what I have read on SNet). Better off with a different chip. A few guys on here could help you. Jollygreenmonster, Scott.T are a couple. I'd PM them and ask their advice bud. I'm sure someone else can add a few more names to that list.

thats a guess. the guy who got the car before me, off the original, said the 1st guy had it chipped years ago, and my mate got it rolling roaded at 285 horses, then decided to play with the boost. its goin to AET in time, maybe have the haltec chip done.

You could always have a look behind the plate in the passenger footwell if you want to find out. If nothing is present there have a look inside the ECU and post up some piccys.

How much is Haltec? Seriously, if you are thinking of remapping speak to the above named people.

haltec is around 550. its done by AET turbos who are trusted and are part of west yorkshire impreza owners club

Products

JollyGreenMonster.co.uk

Try here for a comparison.

will have a gander, cheers :thumb:

pinchers,

I've had some reasonable experience with a Dawes MBC. I wrote up my experiences below:

Scoobypedia | Trusted knowledge for everything Subaru | Projects / Newage Cheep Modifications

IMHO I don't think you are going to gain a whole lot as yours is already PPP'd. The main gain is likely to be quicker spool up. Dialing in a little extra boost than the PPP will be difficult as you have to set it up in 5th at WOT otherwise it will hit fuel cut all the time. That will likely mean you'll end running the same or slightly less boost than your PPP in gears 2, 3 and 4. I ended up having to adjust it a few times a year in line with the weather.

The only other thing you might gain is running more boost in 1st and 5th gear than your PPP now. Your ECU (well MY03 ones do - so assume MY02 do also) pull boost a little in 1st and 5th gear for extra safety. With the MBC your ECU will no longer have control over this.

A bad thing - you will be able to run full boost (set by your MBC) even when your engine is cold. Your ECU currently pulls a little boost in all gears until the water temperature warms up. With a little self control you can work round it i.e. don't boot it until your car is warm.

As recommended above a boost gauge is a must. Better still buy a cable (for the same price a good quality boost gauge) and run some Open Source software on your laptop to do live data logging and graphing of everything and anything your ECU is monitoring.

Good advice.

Hey crispyduck, the info you gave was good reading, gonna give some of the home made decats a go i think and gonna go for a data logger.
cheers for the info.

No problem, glad it helped. Let us all know how you get on or if you have any questions.