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Re: Building an engine?

To: datsun-roadsters@autox.team.net
Subject: Re: Building an engine?
From: RacerY@comcast.net
Date: Sat, 08 Apr 2006 20:30:02 +0000
The lazy way to do that is to use U20 flattops...
but it usually leaves you with a pretty low compression ratio.

When I pulled the engine from the 1600, it had little shiny smiley faces on the 
tops of the domes!  The pistons had been just kissing the head as the bearings 
wore.

Now I have flattops...  maybe it'd be good for a turbo?

Toby
 -------------- Original message ----------------------
From: Keith0alan@aol.com
> Here is what I did on the R16 engine I am currently rebuilding. The head  had 
> been shaved too many times so the pistons hit the head with no head gasket  
> (the normal test for fit). I cleaned the head and pistons and put a thin film 
> of  oil on the pistons. Laid the head on the engine with no head gasket and 
> turned  the crank till the pistons just touched the head. Pulled the head and 
> looked to  see where the oil transferred. Using the sandpaper flap wheel in 
>the 
> die grinder  I removed a small amount of material from the head where it 
> touched. Cleaned  things up and put the head back on the engine and checked 
> where it 
> touched  again. After about 50 to 100 times the head perfectly matched the 
> pistons (and I  added 3" to my arms). This restored the squish band area to 
> where is was  supposed to be. When I measured the combustion chamber volumes 
> they 
> were within  1%, Lucky considering the shaving that had been done on this 
> head. If they had  not been so close I would have removed material from the 
> pocket 
> area to even  them up. The final compression ratio ended up being just a 
> little over the 9-1  stock ratio, about 9.3 as I recall. 
>  
> A proper squish band engine setup is very efficient. It allows higher CR  and 
> better performance that more exotic things like the original hemi head. (the  
> current "Hemi" is a registered trademark and has nothing to do with the  
> combustion chamber shape. My bet is that it is a squish band engine.)
>  
> Enough rambling for now
>  
> keith williams




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