Scott,
I would imagine you could shave more than .060 if you notched the pistons
for valve clearances. This is done often on "regular" engines and I'd be
interested in hearing from a guru if this shouldn't be done with an LBC.
On another topic......The head on my 56 A is cracked across the "tit"
separating the intake and exhaust. I believe the shape of this combustion
chamber is similar to another earlier F*** head and when this occurred in them
they were just machined off......slightly and evenly. It's the only flaw after
magnifluxing and I think I've read these "tits" just get hot and cause
detonation
anyway so I don't see any reason not to proceed and then measure the CC
afterwards
to make them all the same.
Any input would be appreciated.
Thanks,
Gregg Baker
At 05:02 PM 2/22/98 +0000, you wrote:
>I have a 1965 cylinder head with the large combustion chambers on my
>1972 18V engine. As a result, my compression numbers are in the
>cellar. This also causes me new problems when I'm looking at
>pistons, because if I order the pistons for a 1972 engine, they're
>expecting the smaller combustion chambers, so I get a low
>compression ratio. If I order the older pistons that will work with
>the head, I have the wrong connecting rods. Since I just got the
>engine rebuilt in November, I'd like to fix my CR woes without buying
>new pistons or rods at all.
> Is it possible to shave enough material off of the old large-chamber
>heads to reduce the chamber size to that of a newer head? If I can
>do this, I can just order the newer 18V pistons, and the compression
>ratios will be as advertised in the catalog. If not, can I use the
>older rods and pistons with the old head in a 18V engine?
> I know I can order custom pistons from Venolia, but would prefer
>using a standard part. I could also just break down and buy a 18V
>head, but my old head is straight, uncracked, and recently completely
>rebuilt, so I'd like to hold onto it.
> Does anyone know how much I'd have to shave the head to make the
>chamber volume equivalent to a 18V head? I know I can take off .060,
>based on the recommendations of some of the list members, but I don't
>know what this reduces the chamber volume to.
>Thanks,
>Scott
>
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