robbo_64

John (Banks) may be able to answer this one.
Set my Dawes up to 15.5 psi, everything seems OK around 2000-5000 rpm. If you push on further the boost tapers away, albeit slowly to about 10psi. Is this normal?
I was hoping that the Dawes would increase/widen the boost curve.
Further up in the rev range the car is producing less boost than standard, but more in the midrange.
As it stands, I think I am better off returning to standard.
Is there anything I should be doing/checking?
Thanks,
Neil.

john banks

Seems odd that it is producing less. But on a small turbo it does taper and no boost controller in the world can fix that. Sometimes it can feel flatter at the top end because it is quicker in the midrange. On a cold night my car will hold 15 PSI at 6000 RPM in 4th gear. On a warm day it is about 13.5 PSI.

robbo_64

Thanks for the reply, John.
I fitted the boost gauge and ran the car for a week before I fitted the Dawes to get a feel for the characteristics of the standard car (MY98). The car was peaking at around 14 psi then tapering away to about 12 psi at 6-6500 rpm. On the well-lane dyno, most other cars were producing slightly more than this, hence I went for the Dawes to try and improve this.
The car is much better as you say in the 2000-5000 rpm range then feels as if it runs out of breath at the top end as the boost drops away to 10 psi.
This may be the efect you are talking about as it does feel much better in the 2-5000 rpm range where you spend most of your time !!
May take the Dawes off and see how it fares as standard again.
If this fails, may have a go at your fuel cut defender/waste-gate actuator/restrictor mod !!
Cheers,
Neil.

john banks

You should be able to get at least the boost you had at the top end unmodified even without changing the actuator though. Let us know.

robbo_64

John,
will have a try tonight,
Thanks,
Neil.