<VV> Turbo Exhaust Housing Question

[kevin nash]

> 
> Message: 5
> Date: Thu, 23 Apr 2015 16:24:17 -0500
> From: Nick R <nraeber at gmail.com>
> To: virtualvairs at corvair.org
> Subject: <VV> Turbo Exhaust Housing Question
> Message-ID:
> 	<CALb33CwgbTdXor5OWawhx-xiW_B4oQQPNk7WhSFJ66UWoMzbUg at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
> 
> I am reassembling my 150 turbo. One of the first steps is to inspect the
> exhaust housing for pitting or cracks or problems with the threaded areas.
> The inner contour of the one I am using has the tongue intact, but the
> inner contour looks a little rough or pitted, kind of flaky in appearance.
> See the photos that I have attached.
> 
> My question is this. Does this exhaust housing look acceptable for street
> use, not for racing. I am guessing that the pitting might cause diminished
> boost pressure due to a larger tolerance of fit. I am not concerned with
> making maximum power, I just want it to work similarly to the way it would
> have worked when the car was new. What do the more experienced turbo guys
> have to say about it?

I pretty sure that your housing will work fine for what you are doing, however, it would not be a bad idea
to try and smooth out those rough spots- particularly those high spots, just to help keep the carbon deposits 
down when not boosting. I remember when I had my exhaust housing off for inspection, it was not nearly as rough as yours is, but mine was set up with quite a bit tighter than stock clearances. Tighter clearances, for the most part, reduces lag and reduces somewhat the engine rpm required for boost- it doesn't really "increase power" like you might think because the carburetor ends up stopping the turbo from boosting more. I have in the past used a late turbo on my early, and even though that turbo also
had an E-flow compressor, the exhaust impeller was so big (in relation to the engine displacement) that the combination was more laggy than the stock turbo using the same carburetor with both turbo's.  
Kevin Nash
63 Turbo, EFI daily driver