I would have to agree with Lawrie here. The only other
thing I might add is this.
If you insist on increasing compression there are better
ways. All are more expensive and more complicated, but
better. MGs are not known for their strong heads, milling
anything off the head will increase compression and power
but at the expense of the integrity of the head.
So you can reduce the combustion chamber size by using
special pistons; or, milling the block (you still have the
integrity problem, this time with the block); or, changing
the length of the connecting rods; or, index grinding the
crank.
I would prefer any of these methods over milling the head.
Having said all this you would do yourself a favor by
reading Lawrie's comments again.
Good luck and have fun.
Larry Hoy
> -----Original Message-----
> From: owner-mgs@autox.team.net
> [mailto:owner-mgs@autox.team.net]On
> Behalf Of Lawrie Alexander
> Sent: Tuesday, February 15, 2000 5:51 PM
> To: Rick Jennings; mgs@autox.team.net
> Subject: Re: Cylinder head modifications
>
>
> Rick,
>
> My only caution, based on many years experience
> in the trade:
>
> Unless you are planning to use the car for racing
> only, using racing fuel,
> do not exceed 9 to 1 compression. Your engine is
> virtually guaranteed to
> ping and run on, causing expensive damage to
> pistons and bearings, if you
> exceed this figure. 92 Octane just cannot handle
> that high a compression
> ratio.
>
> Lawrie
> British Sportscar Center
> -----Original Message-----
> From: Rick Jennings <ahhclem@kcnet.com>
> To: mgs@autox.team.net <mgs@autox.team.net>
> Date: Tuesday, February 15, 2000 1:12 PM
> Subject: Cylinder head modifications
>
>
> >Does anyone know the stock combustion chamber
> volume of the cylinder head
> >for a 1977 MGB, US spec.. I need to calculate
> current compression ratio in
> >order to determine how much to skim off the head
> to get ~ 9.5 to 1
> >compression. Any cautions on skimming the head?
> Valve to piston clearences,
> >etc......
> >
> >Thanks
> >
> >1977 MGB, decapitated
> >
>
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