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Old 22 March 2002, 12:30 PM
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Mad Matt
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I have a standard 1993 Legacy Turbo and would like to know what the std boost pressure is?

Can i safely increase this by use of a bleed valve and if so what pressure can i safely increase to.

The car has done 130K miles but has had the engine rebuilt 3K ago.

If i increase the boost do i need to alter anything else e.g. fuelling?

thanks in advance
Old 22 March 2002, 12:46 PM
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Dizzy
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try drivetrain......
I "think" you'll be running about .7bar and the easyest way to increase boost is too buy a dawes device (£35) but you'll have to get a boost gauge and afr meter. Theres loads to read up on in drivetrain
Old 22 March 2002, 04:11 PM
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Dr Hu
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Standard boost pressure on the Legacy Turbo is 11 to 12psi MAX.

The Impreza (early 93, 94 95, 96my) with essentially the same engine ran 14psi standard.

You can install a Dawes to improve boost pressure, but watch out for the lower fuel cut on the legacy and be careful of knock. The legacy was more prone to knock....especially with the rattly tappet feature standard on all early legacy's!

Make sure you only run it on SUL or even better Optimax to try to raise the knock threshold.

Old 23 March 2002, 08:08 PM
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sanders
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Mad Matt,

I own a 92 legacy turbo estate, and I had a boost gauge fitted and it showed that my car was running 10psi. I have now fitted a blitz induction kit, scooby sport back box, a bleed valve and an ABC superchip, it is now running 15psi of boost and what a difference it has made to the way the car feels.

Cheers,

Sandy
Old 24 March 2002, 02:17 PM
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ustolemyname??stevieturbo
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I have a 92 ( UK )legacy turbo estate too. Full exhaust, airfilter, and Blitz boost controller. I have safely run 1 bar for a long time. It really does make a huge difference. Mine was running 10 psi std. Import legacy RS cars wont tolerate this high boost for long though, a friend went throught a couple of engines finding out. About 12psi would be the max for the jap model.
With regard to turning the boost up. I did originally tried a couple of methods with bleed valve type devices. This only resulted in hitting the boost cut ( approx 16psi ) on cold nights, and sometimes in higher gears. The Blitz controls the boost much more accurately allowing closer running to the boost cut without actually hitting it. Even if you do get the occasional surge, it is easily turned down from the drivers seat. Also spool up is much faster with one fitted compared to a bleed valve.
Old 25 March 2002, 08:29 AM
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Mad Matt
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Thanks for the tips. Just one more question, I have a custom-built stainless steel rear box, which makes a difference ( I have been quoted 5 BHP) . If I was to remove the Cats would I have to make any ECU mods? And would this gain effect the Boost pressure?
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