subaru legacy twin turbo


hi can anybody help ,ive just got a legacy import 280bhp and want a bit more out of it without goin internal, getting lag on primary turbo about 4000 rpm till the secondary kicks in at 5000 rpm.still got both cats on and no one seems to have a decat for it.any help much appreciated
Hi Phil1221. It's good to have you along. I would look for tech upgraded a boost controller will help address some of the lag issues and a reprogrammed ECU will help raise the power output by another 40 odd bhp!

Sounds like a really nice car. What colour is it? Sounds like you might have a dodgey turbo as something usually should start happening at 2000-3000 rpm.

A decat can be created with a simple pipe and a bit of machining - so most places should be able to knock something up for you. Put a post in the makes and models section - you're more likely to pick up some other owners comments and suggestions that way.

Hi its the estate in gloss black,spotlessly clean and shiny. i got an added bonus when i received it .there was over £3000 of tein suspension on it,
The japs no how to look after there cars the turbo,s have bin checked and are fine .
sorry more power needed.

i was told that the waste gate was opening to soon thats why i have lag between the two but there is no adjustment on on the actuator
Nice surprise with the Tein stuff!! A boost controller will help open the wastegate a little later. You sure the wastegate is not sticking.

no i dont think the waste gate is sticking as the boost is there from 1500rpm till 4000rpm then a short lag till the big turbo kicks in then it takes off literaly ,,i will get the decat exhaust done and the k/n,then get a remapable ecu and a boost controller then i should be ok :?: do you have a legacy
Hi phil1221. Might be worth thinking about a conversion to a big turbo - that might give you lower lags and make it more driveable. A dump valve always sounds great too.

Is the Tein suspension adjustable - if so make sure you tweak it to suit your own preference - it can make a big difference on a cars handling.
hi phil im new to this site i also have a b4 from japan,purple with smoked gold subaru alloys,and hated that lag between 3300 and 4500,im a fabricator and have done loads of exhausts before so i whipped the standard exhaust from uder the car,(the start of where the exhaust goes 2 into 1 under the car up front),thers a cat and a silence in the straight section and then the backbox,its 60mm tube so i replaced the entire length with slightly bigger 75m(3inch)stainless,first thing it SOUNDS AMAZING!!!!! what a growl form the boxer engine you can really hear whats going on,and i instantly noticed the power gain the flow gain was so good the it now pulls strong through the old lag point 3300 -4500 ish,would reccomend to do this 110% glad to help(i hope to take the second cat from the downpipe<its in the left side downpipe from the turbo its two into one)
Hi Phil and welcome to TorqueCars, thanks for the info. I think I read your posts in reverse order! Thanks for the advice.
hi there the lag is well know in the legacy forum it is called the valley of death it is where the first turbo stops spooling and the second turbo begins to spool up. there is no way (other than converting to 1 turbo) to get rid of the v.o.d.
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He did say "almost altogether" Gary! It seems odd that Subaru didn't stage the turbos better. Isn't there a turbo controller like Autronics that can help overcome this VOD?

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