The only reason why I am looking far from Edelbrock amuminum heads
i'm actually not talking about the Edelbrocks. this is the primary Buick aftermarket vendor for small and big block parts, here:
www.TAPerformance.com
you can get any level of head you want from them ( even the Edelbrock ), although the Track Eliminator variants will require use of the TA SP2 intake.
Stage 2+ all mean that the exhaust port dog leg has been milled off and the head must be used with headers, stock exhaust manifolds will no longer fit.
And about the pistons, sealed power tall deck pistons will be ok to replace the stocks?
aluminum dissipates heat faster than cast iron so the rule of thumb is that you can bump static compression ratio about a half point over the equivalent cast iron head build. that's not really a concern until you're getting to the edge of performance though.
the factory 1970 455ci was blueprinted to 10.5:1 while, due to emissions, your 1975 was down to 7.9:1 compression. with alum heads you should be able to go to <11:1 compression and still run premium 90 octane. if you run the stock pistons there should be no problem running the 87 octane US ( i'm guessing this fuel would be rated ~91 for you ) rated regular.
beyond that, you should definitely plan on running race fuel or at least 100LL AvGas. you'll need to remove the catalytic convertors if using AvGas or race fuel as most of those are leaded.
i'm not sure what you mean by "tall deck pistons" ( i assume you mean pin height ), but if you're doing a major rebuild you need to have your block squared and decked by a machine shop as the first step. the shop will also let you know if the bores need to be cleaned up, which will often give you a slight overbore / more displacement although there's no point in chasing <5 ci in a 455ci engine if it's not necessary.
this will give you your actual deck height which is what you need to know in order to plan your rod and piston pin height combination ( this + the combustion chamber space in the head determines static compression ). high performance builds normally aim for piston flush with deck or just slightly recessed.
for a minor street rebuild, you'll want a new cam, get rid of emissions crap and heads / headers can be part of that. definitely make sure the distributor and carb get a reputable rebuild as well.
once you start getting into new pistons and rods, that's a decent amount of expense and hassle, you may as well do it right and get everything ( including oil passage upgrades ) done.
The way to crush the bourgeoisie is to grind them between the millstones of taxation and inflation.
Vladimir Lenin
Government schooling is about "the perfect organization of the hive."
H.H. Goddard, Human Efficiency (1920)
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