zoton

Guys

Fairly new to the Subaru. I have a UK MY00 and would like a little more boost nothing massive. I fitted a bleed valve to a Mk2 MR2 Turbo and got lots of benefit, but I hear that the small turbo on my car doesn't have much if anything in reserve. The Toyota was happy to blow more air.

Worth it do you think?

Thanks

Z

harvey

iTrader: (48)

Instead of a Dawes fit a GBE and yes, if you "only" have a TD04 it is still worthwhile. Do not over do the boost and get your AFRs checked to make sure you are still safe.
GBEs are available from Alyn at AS Performance. info@asperformance.com

zoton

Duh a GBE? Is this a similar device?
Many thanks Harvey, happy to follow your lead

The_Judge

The GBE equivalent is very similar. I have the MkII, featuring a lightweight ceramic ball and a 1mm breather hole as standard. It's supposedly much more accurate than the Dawes. I haven't used the Dawes, so can't comment on that. The only problem with it was the lack of hose that came with it (ie, none), and as the ends of the device are much wider than the compressor outlet and wastegate actuator connection, you need 2 different bores of hose, making it a little bit more awkward.

There's apparently a new version called the "Evo" that comes with 1 metre of silicone vacuum hose, with a bore of 5mm. It also has a right angled exit connection, making twist adjustments far easier, by not having to loosen hoses, adjust, tighten hoses.

Click here for Grant Baker's website, to buy direct.

It's definitely worth doing, as long as you're sensible and keep an eye on what's going on under your bonnet. Knocklink is a must...

ozzy

Yes, it'd definetely worth it, but as others mentioned you need to take precautions when running more boost on an Impreza.

Boost gauage and Knocklink are essential, plus I'd recommend an AFR meter to allow you to monitor the fueling.

Stefan

Dark Blue Mark

Hmm, not heard of one of them. Sounds easier to use than a Dawes tho Judge.

MB

ozzy

GBE is the same idea as the Dawes. It was a lot cheaper until they started charging £42 for it with the silicon hose.

Personally, I would just get a Dawes 2nd-hand from someone on SN.

Stefan

Dark Blue Mark

I would if I didn't have an STi!

Boosts quite high anyway, and they're not reccomended on JDM's apparently... Had one on my UK99 though, worded well.

MB

The_Judge

Yes, worded very well. Grammar, spelling, punctuation, all very good.

ozzy

They do control boost very well. JDM cars are very sensitive to UK fuelling, so you need to be over-cautious when upping the boost. A re-mapped car can still benefit from a Dawes as it controls boost very well. IIRC John Banks still uses the Dawes as a boost controller on his highly mapped car.

Stefan

Dark Blue Mark

Judge you ****! Well spotted Shouldnt that be a silver star?!

Ozzy, I think I would go for it with a remap, one day when I can afford it Guess it would be a good device to cure boost spikes in the cold etc.

MB

ozzy

MB,

You can fit the Dawes and still run stock boost; you'd just use it to handle your boost spikes. IIRC it would run boost at different loads from the ECU map, so perhaps you'd still need a re-map to compensate.

Someone more knowledgeable than me would need to explain just how the MBC's control boost, but their primary function doesn't have to be simply increasing the boost.

Stefan

Dark Blue Mark

Agreed the Dawes etc is reckoned to give better control and smoother spool etc, but I read somewhere a long time ago they weren't to be used on WRX / STi cars?

I think it was John B who posted it.

John?

MB

john banks

From what I've seen, STis and P1s run too much ignition timing to safely allow you to use an MBC with a good margin for safety without monitoring or high octane fuel.

On the 99/00 UK assuming a healthy fuel system, I don't think the TD04 could flow enough to make it lean, but there could be excessive ignition timing if you go over 1.1-1.2 bar on Optimax.

The_Judge

The TD04 may not be able to flow enough air to make the AFR sufficiently lean, but it sure can generate enough heat to cause problems...

ozzy

Thanks John. Is it safe or even beneficial to use the Dawes to simply control boost spikes if you set it to stock boost levels?

Stefan

The_Judge

Possibly, as you're taking two potential boost spike culprits out of the equation - the restrictor and the wastegate solenoid.

galv

I used a Dawes and i found on the dyno the boost was unstable.

The_Judge

It does take a bit of time to set up properly. If you just bung it on the car, turn the boost up and drive, chances are it won't do exactly what you want it to do. However, that said, the GBE is quicker and easier to set up than the Dawes, and doesn't involve as much fannying around...

zoton

Thanks to all for the advice.

To summarise

Better brakes
Knocklink
Boost gauge
Boost controller
Optimax
Start raising boost slowly and time to set up properly.

I know each car varies but if 1.1 bar is the rough ceiling am I right in thinking the standard MY00 UK Turbo is at about 0.8-0.9 bar?

Z

The_Judge

Better brakes - what's wrong with your standard brakes? Mine (MY00 also) are fine...! (and I don't drive like a girl either, before you start DBM... )

Knocklink - absolutely essential.

Boost gauge - indeed.

Boost controller - rude not to.

Optimax - most definitely. You may or may not need octane booster. I'm experimenting at the moment (), and have come off my usual BP Ultimate + Millers to just Optimax on its own. Seems at least as good as, if not better. Bizarre.

Start raising boost slowly - seeing as you haven't fitted an FCD, definitely.

I think 0.8bar is about right for standard. Mine was 12psi (well, 16psi actually, as the Autometer gauge was fcuked out of the box. Either that, or the air pressure in the Midlands is 4psi higher than everywhere else... )

I'm still messing to find the optimum boost level. There doesn't appear to be a right or wrong value. I did have it as high as 18psi, which sometimes was blindingly quick through the lower gears, and other times I felt I could have got out and pushed it faster. But the Knocklink scared the crap out of me on the motorway, so down it went to 16psi. It seems to be more consistent, not as quick as the "good days" at 18psi, but not far off.

There's only so much you can do with the TD04. You soon come to the conclusion that the only way forward is a Tek3. I'm just struggling to justify the money side of that. Of course, you could always replace the turbo, but that would also need a remap, so extra ouch to the wallet...

easyrider

Boost is brought in quicker/more abruptly with a Dawes due to the Wastegate actuator not seeing any pressure untill the dawes pressure level has been reached.

Definately gives you more of a "kick" even when run at std boost levels.

easy

Dark Blue Mark

Didn't say a word I'd never suspect you drive like a girl

MB

The_Judge

zoton

Excellant

The brakes are now TSL Group N (same size and Ferodo pads). The reason for change wasn't to upgrade but the standard discs had a surface a bit worn....kinda -~~~- if you know what I mean.

Interesting how quickly a boost controller becomes a nice new big hybrid turbo Sadly I just know that I will be selling my first born for the best set up as soon as I get use to the increased power!

Z

Flat Faw

Why not just do one clockwise turn on actuator rod? John Banks earlier posts indicated this was a better option to dawes etc anyway. And I completely agree.

I have MY00, only mods are full decat, K&N panel and 1 full turn of actuator rod. Always run optimax. Just done 257bhp at well lane. Previously did 233bhp on same rollers with same spec but no actuator tweak, although admittedly on a hotter day. Alowing for air temps, its still imprezzive.

And FREE!!!!!!!!!!!!!!

Martin

roguck

without sounding silly, where do I find the actuator rod to turn in a MY99 engine please.

john banks

Actuator adjustments WITH A FCD are another method.

Actuator adjustment alone will only make it spike more unless it was not reaching target boost, which is 13.7 PSI on a 99/00 UK.

Dawes at standard boost level will help a bit at the top as the boost will not drop off as abruptly and release a bit of power.

Perilay

Ok, so where is the actuator rod on a MY99?

Perilay

BTTT :P

Anyone??