Hello all,

I fitted (using ozzy's guide) a dawes device to my my99 uk turbo a few weeks ago and all seemed fine.

boost holds steady at 15ish psi with a spike of about 1psi.

However... tonight on the motorway, in 5th the boost spiked all the way to fuel cut, it did this several times.

Off the m/way in lower gears it seemed ok again, approx. 1psi spike.

Any ideas?

I do seem to remember(but can't find) a thread about increasing the bore of the dawes....

I thought these thingies stopped boost spikes altogether?

cheers in advance
eddie

 

Are you talking about a bleed hole of about 1.2mm? I think John Banks had a thread going about this.

Its not a case of the pipe from the dawes coming loose and no pressure getting to the wastegate? This however would not explain the return to normal? Hmm?

 

That sounds familiar.

It's done it again this morning, fuel cut while passing big lorry....arrggghhhh,
change pants n' remove teeth from steering wheel time.

On the way home (slightly warmer outside temp) it boosts upto 15ish in the lower gears, and then in 5th it seemed to hover just below 17(by my guage).

Why should the pressure bursting point change?????

Could the ball be getting stuck?

or do i just need to turn it down a bit now its getting bedded in?

cheers
eddie

 

There is more boost in 5th than in 2nd or 3rd.
Is the dawes regulated for 15psi in 5th?

To remove the boost spike (almost at all), I recomend drilling the hole to 1,5mm.

Regards

Nuno

 

thanks for the advice.

I'll go get a drill bit tomorrow.

eddie