code5@ibm.net wrote:
> I just took my 1600 engine parts to a machine shop today.
> I could use some advice on ways to improve performance.
> I want to increase the power but don't know which are the
> most cost-effective ways to do it. One mechanic I talked
> to (Kim Graff--Amsterdam NY) advised an aluminum flywheel,
> a "mild"cam and stainless steel valves with 'flowed' stems.
> I've read about porting, increasing the compression ratio
> with flat pistons, etc. Will boring it out make a difference,
> or will I also need a new head? I don't want a race engine,
> but would like to get the most performance for the money I
> put into customizing it. I'd appreciate any tips from the
> group.
I'm assuming that you have the stock 1588cc cylinder head and 8.3:1 CR.
IMHO,
the most cost-effective way to increase power is replicate the changes
made to the
1622cc engine ... cylinder head and pistons.
Replace the 1588cc cylinder head with a 1622cc/1800cc (early 'B')
cylinder head ...
this head has larger valves and vastly improved porting. 3 angle valve
seats, modified
valves, and additonal porting as outlined in Peter Burgess's book are
highly recommended.
Replace the dished pistons with flat top pistons ... when combined with
the later head
this will give you approx a 9.0:1 CR. The later head has a larger
combustion chamber
size (43cc), so you must either fit flat top pistons like the 1622cc
(stock 9:1 CR) or (if
you retain the stock pistons) shave the head to maintain the stock 8.3:1
CR. Flat top
pistons are available for the 1588cc ... you might be able to overbore
and use the
standard 1622cc pistons, but this is pure conjecture on my part ...
overboring can lead
to cylinder wall flex and overheating.
A mild fast road cam, in conjunction with the above mods, is
recommended, but be
conservative or the bottom end power will suffer.
The 'A' exhaust manifold is restrictive ... a 'B' manifold can be
utilized, but this is not a
bolt-on replacement (see Barney's excellent post the 1800cc engine swap)
... an 'A'
tublar header is an alternative, but this will increase engine
compartment temps when
compared with the stock cast-iron headers.
Fitting the an aluminum flywheel or lightening the stock flywheel will
allow the engine
to rev faster, but won't increase provide an increase in power. This
mod has an impact
on the 'feel' of the clutch that takes some getting use to ... IMHO,
perhaps a bit more
appropriate for a racing engine.
Hope this helps ... let me know if you would like me to go into more
detail.
Safety Fast! ... larry.g.unger@lmco.com
'61 MGA 1600 MkII
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