B4 single Turbo

[hawks123]

I have recently found that the primary turbo on my B4 may have popped, will find out for
sure later today.
This may have been covered before but i would like peoples current opinion.
If you have driven a Twin Turbo B4 and a Single Turbo B4 could you please give your
opinion about changing it to single, and any pro's and con's you can think of.

Thanks

[Spec B Wgn]

the best thing about converting to a single turbo would be you end up eliminating the VOD... (valley of death) ..

the spot when the first turbo cuts out and the secondary one cuts in...its always been a problem in the B4's and is eliminated when converting to a single turbo.

[GTSPECB STI]

+1 on getting rid of the dreaded VOD

Plenty of good options out there for replacing it. Downside is you will need to spend additional $$ on supporting mods like new piping. Also much easier to get good tuning results in this set up. Spec C Twin Scroll or VF38 which is cheaper.

[swingn]

I've been in a B4 before & I actually didn't think the whole VOD thing was as big of a deal as some make it out to be... But it is there.

Having said that, if your up for a turbo replacement, I'd probably go single turbo option. I mean, Subaru went away from the TT set up for a reason... & just look at all the crazy Supras & GTR's, most of them are back to a single turbo.

[hawks123]

I've been in a B4 before & I actually didn't think the whole VOD thing was as big of a deal as some make it out to be... But it is there.

I agree that's it's not as bad as what it's made out to be. But when you own one you do realise why it is sometimes a very bad thing.
If you want to go real fast you just keep the revs high, if not then keep them low.
But i find it most noticeable when passing some one, have to have the engine sitting on around 4500rpm before planting the throttle to safely get past.
I was thinking also of future servicing costs and parts if something went wrong with a single setup. Cheaper i would have thought.

[Spec B Wgn]

at the end of the day yo are up for some $$$$ with either a rebuild of the blown turbo or fitting the single unit..

servicing & additional costs will be equal in both cases you just have to decide whether you want a single turbo or the original B4.

in saying that i think pehaps when you go to sell , someone might actually want the twin turbo set up due to its factory appeal..

if the VOD isnt an issue for you and the second turbo is still running fine i would fix the bung one and live with it..

wouldnt hurt to get a opinion though on the second turbo just in case its on its way out.

[B.C]

there's usually some second hand VF33 and VF32 floating around on the forums. that's your cheapest option. i went this way as well. never had another problem since . single would be good but again i'd get a full list together of all parts needed and then start shopping and collecting parts as you find them. one day my b4 will self destruct , when it does hopefully i'll end up with a 2.5lt single turbo. problem is she's running just fine ATM hehe

[hawks123]

Well i think i will just go a rebuild now, since kruds money will hopefully cover it.

3 questions though.

What VF numer is the primary?
What manufactuer makes these?
Who could any of you here reccomend in melbourne for a rebuild, or exchange part?

[B.C]

VF33 is primary made by IHI