Date:         Mon, 27 Feb 1995 16:24:25 -0800
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         "Erik Soule"  <erik@henries.nsc.com>
Subject:      Re: Engine update

 
> Here's another:  I CC'ed the combustion chambers, and got them all to within 
> ..5CC of each other.  So I measured the deck height and got .089" and the CR 
> is 7.7 to one.  This is with .040" shims, without them,  CR= 8.45 to one.  
> The jist of it is that the shims must be factory, or else the CR would be 
> through the roof.  The case is a T3, late 70 - 71.  I think these had 7.7 to 
> one CR right?
> 
> Does anyone have an opinion on 7.7 to one or is this still too high for my 
> bus?
> 
>   Chris Bridge

Chris, I went through exactly the same process about 5 years ago when rebuilding
the motor for my '65 Samba. I'll check my notes when I go home tonight, but I 
remember choosing a CR of 7.5-7.5. I used an 'AE' prefix case (I think this is 
about the same vintage as yours). Berg recommends a CR of 6.9 for buses, since 
they run hotter than bugs with the same motor. *However*, everyone I spoke with 
felt this number was extremely conservative. As a precaution, I have the stock 
doghouse oil cooler as well as a full-flow external cooler (with an electric fan
mounted inside the engine compartment - I tried to stay German with one from a 
Rabbit, but the early Civic fan fit poi-fictly!). The motor runs great, if not a
little *too* cool sometimes if you can believe it, so I put in a thermostatic 
bypass valve.

I'll get back to you with the CR data, Chris.

-Erik.


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