Scooby-Mike

Just tried fitting my dawes device to my my97 turbo 2000 as instructed in a previous thread.
I removed the old pipe between the wastegate and turbo nipple and pulled the pipe off the 't'-piece that goes to a sensor on the wing and blocked off.
I then fitted a new piece of pipe from the turbo nipple to the wastegate with the dawes device inline.
Took the car for a roadtest and only got 5psi of boost in all gears!!

What have i done wrong!!

Mike

stockcar

probs you need to adjust it........................the more "thread" you can see of the Dawes then the less boost you will get..............try adjusting and re-try (don't get too greedy!!)

alyn - asperformance.com

Scooby-Mike

i was told that if no pressure gets to the wastgate i would have unlimited boost, is this correct?
if i wind the dawes out all the way would it not just run the standard 0.5 bar boost??

andydavies

You need to start with the adjuster screwed out quite far. Then see what boost you get, then srcrew it in a bit at a time slowly increasing the pressure. Standard my pressure was 14psi dropping to 12psi. With the MBC its running at 16psi at the moment. If you keep winding it in eventually you will hit the fuel cut. It can be a bit dramatic when it happens so try to build up the boost slowly. I was advised to determine at what pressure the fuel cut is then back off the MBC by 1psi. Even at 16psi the adjuster is not screwed in very far, however my MBC is a JW racing own version rather than a Dawes.
Andy.

zhastaph

When I had a Dawes fitted to mine, I started it at the point where I could no longer blow through the unit. And then turned it in about a turn at a time taking it out and accelerating full throttle up hill in 4th each time in between adjustment.

I found a full turn increased boost by about 2 psi, but you need to get above the threashold of the wastegate actuator before you see any changes.

I woz running about 17psi boost, at this point it was almost fully wound in.

bigsinky

same here. about 1.1bar in gears 1-4 and had to blip the load pedal in 5th coz of boost cut. it is a fine line you are walking my friend. hope you have invested in a GOOD boost gauge and a knocklink sensor and an AFR meter.

cheers

sinky

Scooby-Mike

You said
'you need to get above the threashold of the wastegate actuator before
you see any changes'
so why did I only get 5 psi of boost when wound most of the way out, shouldn't it be standard??

vulnax999

iTrader: (7)

If the waste gate sees turbo boost with no control solenoid, it opens at the spring pressure, which is about 6 - 7 psi ... maybe your spring is weak or actuator rod is loose?

With NO boost seen at wastegate, unlimited boost yes but .... GRENADE motor!!! IIRC

Screwing out your dawes should mean most boost pressure is being seen by the wastegate, and so it opens when it's spring is overcome with the air pressure... as you screw it in it stops ANY air pressure going to the wastegate and so it only sees pressure and opens when the dawes lifts ( i.e. when boost pressure over comes the Dawes spring pressure set by screwing in the screw! )
So screw in more, more boost before Dawes lifts and wastegate sees any boost!

Take care and try it a half turn at a time and try a full boost run ....

As said above, good boost gauge and AFR gauge recommended, but fuel cut will tell ya when you have gone too far!!

Scooby-Mike

Will try again tomorrow, hopefully will be ok. i think its because i didn't screw it in enough.
I have had fuel cut a few times before due to the 2 port sensor on th MY97. don't fancy headbutting the windscreen in a hurry again!!

vulnax999

iTrader: (7)

I have a small wiper blade on the inside of my windscreen to wipe my nose off the windscreen when I hit fuel cut!