Matty P

Hi all, I recently bought a 98MY impreza turbo. When accelerating gently from around 2000rpm to 4000rpm the car seems to surge a little on and off boost, which I think is wastegate creep. It is also a little inconsistant when on full boost. The vehicle is totally standard and I would like to keep it that way. (At least for the near future anyway)
I have read alot of posts about the wastegate solanoid been oiled up so I cleaned that, checked the MAF by disconnecting it (engine cut out), tested and reset the ECU (no faults appeared), car idles well so I'm assuming the Lambda sensor is ok.
My question therefore is without raising the boost pressure can I fit a Dawes device to replace the standard solanoid so that it holds boost more accurately and is nicer to drive.
I would use a boost gauge obviously to set the boost to the standard level but don't really like the thought of haveing it or a knock link in the cabin all the time. I will reconsider this however if I decide to change the exhaust, filter and potentially raise boost levels. Any advice would be welcome, cheers! Matt

SiHethers

Matt

A Dawes Device (or similar mechanical, ball-spring, boost controller) is very good value for money IMO. Even if you keep the boost pressure at standard (ie 13.5psi/0.9bar) you'll still get noticeable gains in spoolup, boost stability (minimal spike/oscillation) and topend power (the standard ecu tends to pull boost back dramatically over 5000rpm, whereas using a Dawes will try and hold your set boost all the way to redline)

In addition you get much crisper-feeling part throttle responses due to boost coming in much harder on small throttle openings. This isn't to everyones taste however, as until you get used to it you may find modulating your accleration in corners difficult.

Having said that, I've got one and love it

Cheers

Simon

The_Judge

Another couple of checks, have you checked the restrictor is completely clear in the hose between the compressor and the wastegate actuator? And what level is your engine oil at?

I've got the GBE alternative. It's definitely worth getting, as it will no doubt cure your current problem, and at the same time, provide you with the option of increasing the boost pressure, as and when you decide to.

You can pick up a boost gauge for very little money, and if you don't want it in the cabin after setting the boost level, it's easy enough to fit and then remove. Or you could do what someone did on here a few months ago. Run the boost hose through the bonnet scoop and attach the gauge to the windscreen wiper... can't remember who, but I nearly pissed myself laughing when I read about it...

Matty P

The oil level is around the 3/4 full mark which I think is about spot on. I haven't checked the hose yet though. Thats my number one job tommorrow.
Thanks for the advice guys, time to go shopping me thinks!