[wynter919]

all sounds like good advice, will look into it,thanks. well took the first step and ordered that jim hands pontiac book

and also as im here and got your attention. what do standard pistons in a 400 1970 look like, i only ask as mine look very new, clearly havent been in there long, i know the guy before me did a basic rebuild but as this is my first 400 i dont know what the pistons as standard look like.
mine have 4 valve relifes in them and have STD stamped on all of them, are these standar or aftermarket?

[72blackbird]

I don't remember if GM stamped STD on the factory slugs, but if if you see L2262F stamped on them you're looking at a set of TRW forged pistons. These used to be about $200/set, but have risen in price to about $340/set now.

If the the bore has less than .001" taper from bottom to top, you could reuse the pistons to save money. I would only recommend cast pistons for a bone stock application- like the factory rods, they will only withstand standard loading. If you're planning to do any type of racing, use forged pistons and rods- the factory parts will fail in extended high rpm use.

Geno